NEET Biology

NEET Biology Morphology Of Flowering Plants Inflorescence And Flower

Inflorescence:

The configuration and method of distribution of flowers on the plant’s stalk system is referred to as inflorescence.

• A flattened peduncle is referred to as a receptacle. A scape is a leafless peduncle that emerges from the ground level among basal leaves, as seen in onions.
• Cauliflower is the flowering of mature stalks. For instance, Artocarpic

NEET Biology Morphology Of Flowering Plants Notes

Types of Inflorescence:

1. Racemose
2. Cymose
3. Mixed Type
4. Special Type

1. Racemose or Indefinite. The main axis is not arrested and terminated by a flower. Flowers are arranged in acropetal succession. The opening of the flower is centripetal.

Kinds Of Racemose Inflorescence

Neet Biology Morphology Of Flowering Plants Notes

Compound Racemose Inflorescence

• Raceme of Racemes (= Compound Raceme = Panicle). Racemes are borne acropetally on a raceme, For Example. Cassia fistula. Delonix regia, Yucca, Asparagus, Aspliodelus.
• Corymb of Corymbs (= Compound Corymb). An axis bearing several corymbs in a corymbose fashion, For Example. Pyrus, Cauliflower. Marketed Cauliflower (Brassica oleracea var. botrytis) represents an undeveloped inflorescence.
• Umbel of Umbels (= Compound Umbel). Many umbels develop from a common point in an umbellate fashion.

2. Cymose or Definite. The main axis and its branches bear flower buds at its apex. Consequently, the growth of the axis is checked. The flowers develop in basipetal succession.

The order of opening of flowers is centrifugal. It is of three types :

1. Monochasial
2. Dischasial and
3. Polychasial

Morphology Of Flowering Plants Neet Notes

Morphology Of Flowering Plants Neet Notes

3. Mixed Inflorescence

1. Thyrsus (Thyrse). Cytnose clusters arranged acropctally For Example, Vilix vinifera (Grape Vine).
2. Mixed Spadix (Spadix of Cymes). Spadices having cytnose inflorescence arranged acropctally on fleshy axis. For Example. Banana.
3. Panicle of Spikclets. Spikelets arranged in a compound raceme, For Example., Oat, Rice.
4. Corymb of Capitula, For Example., Agcratum.
5. Other Types like umbel of capitula. cyme of capitula (For Example. Vcnionia), cyme of umbels (For Example. Lantana). cyme of corymbs, etc.

4. Special Types of Inflorescence

Neet Morphology Of Flowering Plants Chapter Notes

Importance of Inflorescence

1. It provides more chances for cross-pollination.
2. Inflorescence makes flowers more conspicuous. Thus insects are attracted to pollination.
3. A large inflorescence also enhances the chance of wind pollination and simultaneously in many flowers.
4. An insect can pollinate many flowers in inflorescence in a single visit.

Neet Morphology Of Flowering Plants Chapter Notes

NEET Biology Morphology Of Flowering Plants Flower

A flower is a reproductive shoot that bears sex organs and performs the following functions,

1. Production ofpollen and ovules,
2. Pollination
3. Fertilization
4. Development of fruit, and seeds and their dispersal.

• Achlamydeous. A flowering lacking both calyx and corolla, For Example., flowers in a cyathium inflorescence.
• Complete. A flower with all four whorls.
• Neutral. When sex organs are not developed, For Example., ray florets of sunflower.

Sex-Distribution

1. Bisexual, perfect, or monoclinous. A flower with both sexual organs, i.e., stamens and pistils.
2. Unisexual, Imperfect, or diclinous:
   • Monoecious. Both male and female flowers are present in the same plant.
   • Dioecious. Male and female flowers are present in the different plants.
   • Polygamous possess more than two types of flowers For Example. Mango and cashew nut trees possess three types of flowers—bisexual, staminate, and neuter.
3. Isoniery. The presence of the same number of floral parts is termed isometry. An isomeric flower is known after the basic number as trimeric (3 or multiple of three in each series), tetramerous (four), pentamerous, or numerous. If different floral organs have different basic numbers it is termed heteromer.

Arrangement Of Floral Parts

• Acyclic. (spiral) Floral organs are arranged in spirals, For Example., Magnolia, Opuntia, and Nymphaea.
• Cyclic. Floral organs are arranged in whorls, For Example., Solamun.
• Hcmicyclic (spiro-cyclic). Floral organs are partly in spirals and partly in whorls, For Example., Anona.

Morphology Of Flowering Plants Class 11 Notes For NEET

Floral Parts

• Perianth. Collective terms when petals and sepals are not distinguished.
• Tepal. A seg-ment of perianth. May be sepaloid or petaloid.
• Polyphyllous. In such flowers, tepals are free.
• Gamophyllous. In such flowers, tepals are fused.
• Perianth segment of the family Gramineae are called Iodicules (Small fleshy, translucent)
• Calyx. It is the outermost series of non-green floral organs called sepals.
• Caducous. Falls away as the bud opens, For Example. Poppy.
• Deciduous. Falls away just after pollination.
• Persistent. Remains attached in the fruit, For Example. Brinjal.
• Accrescent. Growing along with fruit, For Example. Physalcs
• Marcescent. Dried appearance For Example. Piper, Guava, Asphodelus

Aestivation

1. Valvate, arrangement without overlapping For Example., Custard apple, Acacia.
2. Twisted all are in and out or Contorted, For Example., china-rose.
3. Imbricate, For Example., Cassia
4. Quincuncial. A form of imbricate where two petals or sepals are external, two are internal, and one is partly internal and partly external, For Example., Guava.
5. Vexillary or DescendingImbricate, five petals present, posterior outermost, anterior innermost, laterals in and out, For Example., Pea.

Different conditions of sepals are as follows:

• The state of free sepals is called polysepalous (or choriscpalous), whereas the condition of fused sepals is designated as gamosepalous (or synsepalous).
• Based on the incisions, the gamosepalous calyx is classified as toothed (with minimal incisions), find (incisions extending midway), partite (incisions approaching the base), and connate (fused solely at the base).

Morphology Of Flowering Plants Class 11 Notes For NEET

Gamosepalous calyx can have various shapes:

1. Campanulate. Bell-shaped, For Example., Shoe Flower (= China Rose),
2. Cupulate, Cup-like, For Example., Gossypium.
3. Infundibuliform. Funnel-shaped, For Example. Atropa.
4. Urceolate. Um-shaped, For Example., Silene(v) Globose, For Example., Physalis.
5. Tubular. Tube-like, For Example., Datura, Verbena,
6. Spurred. Beak-Ike, For Example. Delphinium (Larkspur),
7. Bilabiate. With two lip-like structures, For Example., Ocimum, and Salvia.
8. Pappus. Hair-like sepals, For Example., Sonchus, Tagetes
9. Spinous. Trapa.

A sepal lying in line with the mother axis is an odd sepal if the number of sepals is 3 or 5. Odd sepal is generally posterior (For Example. Solanum, Hibiscus) but is anterior in Leguminosae (For Example., Pea, Acacia, Cassia) and a few others. Sepals colored other than green are called petaloids.

Epicalvx

It is an additional whorl of sepal-like structures formed by bracteoles that occur on the outside of the calyx. Epicalyx occurs in the family Malvaceae (For Example. Shoe Flower, Cotton, Althaea) and some rosaceous flowers.

Corolla

It is a whorl of the non-green, colored leaf-like non-essential floral organ that forms a series inner to calyx. It is meant to attract pollinating insects.

Some Descriptive Terms Concerning Corolla

1. Polypetalous corolla Choripetalous—It is a condition of free petals. It is of the following types.
   • Cruciform. Presence of four, free, unguiculate petals arranged in the form of a cross For Example. Brassica (Sarson). Each unguiculate petal consists of a lower narrow’ portion called a claw and an upper broad portion limb.
   • Caryophyllaceous. There are five unguiculate petals. The limbs of petals spread outward and lie’ at the right angle of the claw For Example. Dianthus (Pink) and Carnation etc.
   • Rosaceous. The petals are five or more than five having very reduced or sessile claws and large broad limbs spreading outwardly For Example. Rose.
   • Papilionaceous. It is a butterfly-shaped irregular corolla consisting of five petals. The posterior petal is the largest known Standard or Vexillum. Two lateral petals are small and free called Wings or Alae, and are overlapped by the posterior standard petal.
   • The two anterior petals are fused to form the innermost boat-shaped structure covering the stamens and carpel of the flower and are spoken as Keel or Carina.
   • It is overlapped by wings or alae For Example. members of the family Papilionaceae For Example. Pea.
2. Gamopetalous (sympetalous) Corolla: It is a condition of fused petals. It has several shapes
   • Campanulate. Like a bell, For Example. Cucurbita.
   • Hypocrateriform or Salver-Shaped. Tubular with spreading lobes, For Example., Clerodendron.
   • Infundibuliform. Like a funnel, For Example. Petunia.
   • Urceolate. Um-like.For Example. Bryophylliun.
   • Tubular. Like a tube, For Example., disc florets of Sunflower,
   • Ligulate (Strap-Shaped). Flat limb with a tubular base, For Example., ray florets of Sunflower,
   • Rotate. Short tube with spreading lobes For Example., Solatium nigrum,
   • Spurred. With a beak, For Example., Larkspur,
   • Bilabiate. Bilipped or with two lips. The mouth can be open (bilabiate ringent, For Example. Salvia, Ocimum) or closed (bilabiate personate, For Example.. Antirrhinum or Dog Flower).

NEET Biology Morphology Of Flowering Plants Important Points

Incision of gamopetalous corolla may be toothed, fid, and partite. Aestivation can be open (margin sufficiently apart), valvate (no overlapping, margins just touching), twisted (= contorted, regular overlapping of one margin), and imbricate (irregular overlapping).

• Imbricate aestivation has three special types—quincuncial (two overlappings, two overlapped, One with one margin overlapping while the others being overlapped), ascending price (posterior being overlapped by lateral, and lateral being overlapped by anterior petals.
• For Example., Cassia) and descending imbricate (posterior overlapping lateral ones and lateral the anterior petals = vexillary = papilionaceous, For Example.. Pea).

Androecium

It is a collective name of the stamens or male reproductive organs of a flower. Each stamen has two parts, a thread-like stalk called filament and a knob-like terminal anther.

• An anther has two lobes (whether lobes) attached by a sterile band called a connective. Elongation of connective makes the anther lobes divergent (= divaricate) or distractile (anther lobes at the two ends of elongated connective).
• Anther is vitreous (with two lobes) in most cases. In the family Malvaceae (For Example., Shoe Flower, Cotton) anthers are single-lobed and are called monoecious.

Terms Related With Androecium

• Polyandrous. All the stamens are free in the androecium For Example. Brassica.
• Epipetalous. Filaments of the stamens adnate.with petals. It is found mostly in gamopetalous corolla For Example. Petunia, Brinjal.
• Epiphyllous. Stamens arising from tepals For Example. Asphodelus.
• Episepahnis. Stamens attached with sepals For Example. Verbena.
• Gynandrous. When the anthers of stamens united with the stigma of carpels forming the gynostegium Example. Calotropis (Ak)
• Inserted. Stamens are shorter than the corolla tube and remain hidden inside it For Example. Petunia.
• Exerted. When stamens come out from the corolla tube For Example. Acacia.
• Didynamous. There are four stamens out of which two stamens are larger and two are shorter in length For Example. Ocimum, Salvia.
• Tetradynamous. There are six stamens of which four stamens are large and two are short For Example. Brassica campestris.
• Alternipetalous. There is a single whorl of stamens. The number of stamens is equal to the number of petals and they alternate with the petal lobes For Example. Solanum nigrum, Petunia. In the case of tepals, the condition is alterniphyllous.
• Antipetalous. Same as above, but the stamens are present opposite to the petal lobes For Example. Coriander. In the case of tepals, the condition is antiphyllous.
• Diplostemonous. The stamens are double the number of petals and present in two whorls. The inner whorl of stamens is alternating with petals (alternipetalous), while the inner whorl is opposite to petals (antipetalous) For Example. Cassia and Murraya exotica.
• Obdiplostemonous. It is the reverse of diplostemonous. The outer whorl of stamens is opposite to petals (antipetalous) while the inner whorl of stamens is alternating with petals (alternipetalous) For Example. Pink.
• Isostemonous. All the stamens in a flower are alike in shape, size mode of dehiscence, etc.
• Heterostemonous. The stamens in a flower differ in their shape, size, and mode of dehiscence.
• Adelphous. The stamens are fused by their filaments but the anthers are free. If the filaments of all the stamens fuse to form one group, it is termed monadelphous For Example.
• Hibiscus rosa sinensis. When they are fused in two groups called diadelphous For Example. Pea, or sometimes fused in more than two groups and described as polyadelphous For Example Citrus.
• Syngenesious or Synantlierous. In this case, the filaments of stamens are free and anthers are fused by their sides to form a ring around the style For Example Sunflower.
• Synandrous. When both filaments and anthers of the stamens are fused completely.

NEET Biology Morphology Of Flowering Plants Important Points

Gynaecium

It is the collective name of Carpels or female reproductive parts. The free unit of gynaecium is called a pistil. Each pistil has a stigma, style, and ovary.

Terms related to gynaecium

1. Unilocular Ovary. One Chamber For Example. Pea, Sunflower.
2. Bilocular Ovary. Two Chambers For Example. Petunia.
3. Trilocular Ovary. Three Chambes For Example. Asphodelus.
4. Tetralocular Ovary. Four Chambers For Example. Ocimum.
5. Pentalocular Ovary. Five Chambers For Example. Hibiscus.
6. Multilocular. More than five Chambers For Example. Althaea.
7. Apocarpous. There are two or more carpels in a gynaecium that are free from each other For Example. Ranunculus (Buttercup), Aconitum.
8. Syncarpous. In this form, two or more carpels are fused to form a single compound ovary For Example. Petunia, Althaea, etc.

Placentation :

1. Marginal For Example. Pea.
2. Parietal For Example. Papaya, mustard.
3. Axile For Example. China-rose, Petunia.
4. Free central For Example. Dianthus.
5. Superficial, For Example. Lotus.

1. Marginal (L.5.) and (C.5)
2. Parietal
3. Axile
4. Free central
5. Basal
6. Superficial

NEET Biology Morphology Of Flowering Plants Important Points

Forms Of Ovules

1. Orthotropous or Straight. The ovule is erect. Funicle, chalaza and micropyle lie on the same vertical line, For Example., Polygonum, Rumex.
2. Anatropous or Inverted. Ovule bends along the funnel. Micropyle lies close to the hilum. Micropyle and chalaza lie on the same vertical line For Example., Solanum, Anemone, Helianthus.
3. Amphitropous or Transverse. The ovule is placed transversely or right angle to its stalk, For Example., Lemna.
4. Campylotropous or Curved. Chalaza and micropyle do not lie in a straight line. For Example. Capparis, Mustard, Pisum.
5. Circinotropous. In this, the ovule is inverted at an angle of 360° so that the ovule again becomes orthotropous and coiled around by funiculus For Example. Opuntia.
6. Hemitropous. This body is curved.

Relative position of floral parts on the thalamus

The arrangement of floral leaves on the thalamus varies and is of the following types :

1. Hypogyny. When the various whorls of flower are arranged below the ovary, the carpel occupies the central position, and other floral parts airborne below it in their respective whorls. Such flowers are called hypogynous Examples. china rose. In such a case ovary is called superior and other parts are inferior.
2. Perigyny. If the thalamus is flattened out to form a disc or a cup or flask-shaped top, the gynaecium will be placed not on the top of the flower but in the center. The remaining three whorls of flower (calyx, corolla, and androecium) are usually inserted on the rim of the disc or cup or flask-like thalamus.
3. Epigynous. The thalamus is a hollow cup or flask-like but the ovary is completely fused with the inner wall of the thalamus or receptacle. Gynaecium is inferior. Other parts are superior For Example. sunflower, coriander, and apple.

NEET Biology Morphology Of Flowering Plants Revision Notes

Inflorescence (An Axis Bearing Flowers)

Anthotaxis is the arrangement of flowers on the axis of the peduncle For Example. acropetal, basipetal, centripetal.

• Strobile is a spike in which the flowers develop in the axils of persistent membranous bracts For Example. Humulus (hop).
• Thyrsus is a type of mixed inflorescence when cymose clusters are arranged acropetally For Example. grapevine. Puya raimondii (32 ft.) is the largest inflorescence of world.
• Coenanthium is open hypanthodium.
• Petaloid bract is found in Bougainvillea.
• The largest Indian inflorescence is Amorphophallus.
• In rhipidium scorpioid cyme, the lateral branches are present on the same plane For Example. Solatium nigrum.
• In the cincinnus scorpioid cyme, the lateral branches are present on angular planes.

NEET Biology Morphology Of Flowering Plants Revision Notes

NEET Biology Morphology Of Flowering Plants Quanta To Memory

Mussaenda. The odd sepal is enlarged to form a leafy structure.

• Longest Inflorescence. Agave (12 m), Amorphophalus (5.5 m).
• Anthotaxy or Anthotaxis. The arrangement of flowers on the peduncle is called anthotaxy or anthotaxis.
• Goethe (1790) suggested that a flower is a modified shoot. Sepals and Petals or Tepals are the non-essential appendages of a flower.

Stamens and carpels are the essential appendages of a flower.

• Complete flowers bear sepals, petals, stamens, and carpels.
• Tepals collectively form Perianth.
• Polygamous. A plant having male, female, and intersexual flowers, For Example., Mango.
• Trioecious. A species with three types of individuals, male, female, and monoecious.
• Andromonoecious. A plant having male and intersexual flowers, For Example., some Lilies.
• Gynomonoecious. A plant having female and intersexual flowers, For Example., Sunflower.
• Stylopodium. Sunflower base of style.
• Sexual Reproduction in Plants. First studied by Camerarius (1694).
• Most Common Type of Ovule. Anatropous (92%).
• The union of stigma with the stamen is called gynostegium.
• Coronary corona is found in Calotropis.
• Staminal corona is found in Nerium.
• Stamens are branched in Ricinus (castor).
• Syngenesious stamens are those where anthers are fused and filaments are free, For Example., Compositae.
• Sagittate (arrowhead-like) anthers are found in Vinca.
• Stylopbdium is the swollen base of the style in Foenicuhim, Coriandrum, etc.
• A funnel-shaped stigma is found in Crocus.
• Persistent, wheel-like stigma occurs in Papaver (poppy):

NEET Biology Morphology Of Flowering Plants Revision Notes

In cymose-type inflorescence, the growth of the mother axis is definite due to the formation of a flower at the tip.

• In the racemose type of inflorescence, the growth of the mother axis is indefinite.
• Spike differs from raceme in having sessile flowers.
• A spike with a fleshy axis and enclosed by a bract (spathe) is called a Spadix.
• Spikate Head (Capitate Head). The inflorescence of Mimosa, Acacia, and Albizzia is not centrifugal but is centripetal.
• Hypanthodium type of inflorescence is present in Ficus.
• Cup-shaped involucre having a single female flower surrounded by male flowers are the characteristics of cyathium inflorescence, For Example., Euphorbia.
• Monochasial Cyme. Helicoid is of two types :
• drepanium (flowers of different branches in one plane) and bostryx (flowers of different branches in different planes). Similarly, scorpioids are of two types: rhipidium (flowering in one plane) and cincinnus (flowers in different planes).

When calyx is modified into bristle or hair, it is called pappus, For Example., Compositae.

• In the valvate type of aestivation, sepals or petals meet edge to edge without overlapping each other.
• When the filaments are fused to form more than two bundles and anthers are free, the condition is called polyadelphous.
• The intercalary inflorescence is found in Callistemon (Bottlebrush).
• The terminal flowerless portion of the peduncle of the spadix elongates to form an appendix.
• The capitulum (Racemose head) is the most advanced type of inflorescence.
• Pistillode is a sterile carpel.
• The ovules are generally supported by a stalk known as a funicle.
• Erect ovule is called orthotropous.
• In onion and garlic, scape is a hollow, unbranched, long peduncle that bears terminally a cymose cluster of flowers in an umbellate manner.
• Thyrsus. This is an inflorescence in which many cymose clusters are borne acropetally on an unlimited axis in the manner of a raceme. Examples are the grapevine, and lilac.

Morphology Of Flowering Plants NEET Chapter Summary

NEET Biology Morphology Of Flowering Plants Questions From Competitive Examinations

Question 1. Placentation in legumes is :

1. Basal
2. Marginal
3. Axile
4. Free central.

Answer: 2. Marginal

Question 2. Bicarpellary gynaecium and oblique ovary occur in :

1. Mustard
2. Banana
3. Pisum
4. Brinjal.

Answer: 4. Brinjal.

Question 3. The tetradynamous condition occurs in :

1. Cruciferae
2. Malvaceae
3. Solanaceae
4. Liliaceae.

Answer: 1. Liliaceae.

Question 4. An example of a polypetalous zygomorphic corolla is :

1. Crotalaria
2. Ocimum
3. Mustard
4. Rose

Answer: 1. Crotaloria

Question 5. Palynology is the study of :

1. Palms
2. Flowers
3. Fruits
4. Pollen grains.

Answer: 4. Pollen grains.

Morphology Of Flowering Plants NEET Chapter Summary

Question 6. Which of the following is a wrong pairing?

1. Cyme – hibiscus
2. Corymb – caecalpinia
3. Spike – crotalaria
4. Verticillaster – Leucas.

Answer: 3. Spike – crotalaria

Question 7. What kind of inflorescence is found in Apiaceae

1. Umbel
2. Catkin
3. Cymose
4. Hypanthodium.

Answer: 1. Umbel

Question 8. A beautiful whorl which encloses the whole of implore- science is :

1. Bract
2. Involucre
3. Spathe
4. Spadix.

Answer: 2. Involcure

Question 9. Trimerous unisexual flowers occur in :

1. Tamarind
2. Cocos
3. Pea
4. Hibiscus.

Answer: 2. Cocos

Question 10. Choose the mismatched option.

1. Wind-cannabis-anemophilous
2. Water-zoortera-hydrophilic
3. Insects-salvia-entomophile
4. Birds-adansonia-ornithopinily
5. Bats-kigelia-chiropterophilly.

Answer: 4. Bats-kigelia-chiropterophilly.

Question 11. Unisexuality of flowers prevents :

1. Geitonogamy, but not xenogamy
2. Autogamy and geitonogamy
3. Autogamy, but not geitonogamy
4. Both geitonogamy and xenogamy.

Answer: 3. Autogamy, but not geitonogamy

Morphology Of Flowering Plants NEET Chapter Summary

Question 12. In the monocotyledonous seeds, the endosperm is separated from the embryo by a distinct layer known as:

1. Testa
2. Aleurone layer
3. Tegmen
4. Scutellum
5. Coleoptile.

Answer: 2. Aleurone layer

Question 13. The fleshy receptacle of the syconus of fig encloses many:

1. Berries
2. Mericarys
3. Achenes
4. Samaras.

Answer: 3. Achenes

Question 14. Match List 1 with, List 2 and select the correct option.

1. (A)-3, (B)-1, (C)-1, (D)-5, (E)-2
2. (A)-3, (B)-1, (C)4,: (D)-5, (E)-2
3. (A)-2, (B)-4, (C)-1, (D)-5, (E)-3
4. (A)-4, (B)-2, (C)-5′ (D)-1, (E)-3
5. (A)-5, (B)-4, (C)-1, (D)-3, (E)-2.

Answer: 1. (A)-3, (B)-1, (C)-1, (D)-5, (E)-2

Question 15. Replum is present in the ovary of the flower of :

1. Sunflower
2. Pea
3. Lemon
4. Mustard.

Answer: 4. Mustard.

Question 16. The ovary is half inferior in flowers of :

1. Peach
2. Cucumber
3. Cotton
4. Guava.

Answer: 1. Peach

Question 17. Which one of the following statements is correct?

1. In tomatoes, fruit is a capsule
2. Seeds of orchids have oil-rich endosperm
3. Placentati ot in primose is basal
4. Flower of tulip is a modified shoot.

Answer: 4. Flower of tulip is a modified shoot.

Question 18. Flowers are zygomorphic in :

1. Mustard
2. Gulmohur
3. Tomato
4. Datura.

Answer: 2. Gulmohur

Morphology Of Flowering Plants NEET Chapter Summary

Question 19. Phyllode is present in :

1. Euphorbia
2. Australian acaci
3. Opuntia
4. Asparagus.

Answer: 2. Australian acaci

Question 20. Cymose inflorescence is present in :

1. Sesbania
2. Trifulium
3. Brassica
4. Solanum.

Answer: 4. Solanum.

Question 21. Find out the pairs, which are correctly matched concerning
aestivation of Petals.

1. Valvate – caltrops
2. Twist – bean
3. Lubricate – cassia
4. Vexillary – China rose

1. 2 and 4
2. 1 and 2
3. 1 and 3
4. 3 and 4
5. 2 and 3

Answer: 3. 1 and 3

Question 22. Fit out the correctly matched pair.

Answer: 5. Basal – marigold

Question 23. The seed coat is not thin, membranous in :

1. Coconut
2. Groundnut
3. Gram
4. Maize

Answer: 1. Coconut

NEET Biology Strategies For Enhancement In Food Production Animal Sources

Animal Husbandry. It is a branch of science that deals with the improvement of domesticated animals, with regard to race, reproduction, and feeding.

Livestock. The animals like cattle, sheep, goats, camels, horses, pigs, and poultry form the livestock.

Apiculture. Rearing and management of honey bees for obtaining honey and wax is called apiculture.

Poultry Fanning deals with the rearing of game birds such as domestic fowls, ducks, turkeys, and pheasants which yield eggs and meat, rich in protein and other nutrients.

Aquaculture is the production of aquatic plants along with animals like prawns, fishes, oysters, etc.

Piscicultural Practices (production of fishes) differ depending on whether the fishes belong to freshwater or marine water.

Marine Fishery practices include trapping and collecting by using trawlers, nets, baits, electronic locators, etc. The most important edible freshwater fish in India is the rohu. catla and Singhara: marine ones arc Bombay duck, hilsa, and pomphret.

Strategies For Enhancement In Food Production Class 12 NEET Solutions

Strategies For Enhancement In Food Production NEET Notes

Animal Husbandry

Animal husbandry is the agricultural practice of breeding and rearing livestock. Consequently, it is an essential skill for farmers, embodying both scientific and artistic elements.

• Animal husbandry pertains to the management and breeding of livestock such as buffaloes, cows, pigs, horses, cattle, sheep, camels, and goats that are beneficial to people.
  It encompasses poultry farming and aquaculture.
• Fisheries encompass the cultivation, capture, and sale of fish, mollusks, and crustaceans.
• Since ancient times, humans have utilized creatures such as bees, silkworms, prawns, crabs, fish, birds, pigs, cattle, sheep, and camels for products like milk, eggs, meat, wool, silk, and honey.
• It is believed that over 70 percent of the global livestock population resides in India and China.
• It is noteworthy that the contribution to global agricultural output is about 25 percent, indicating a low productivity per unit.
• Therefore, with traditional methods of animal breeding and care, it is essential to implement advanced technology to enhance quality and output.

NEET Biology Strategies For Enhancement In Food Production Dairy Farm Management

Dairying is the management of animals for milk and its products for human consumption.

• In dairy farm management, we deal with processes and systems that increase yield, and improve the quality of milk,
• Milk yield is primarily dependent on the quality of breeds on the farm. Selection of good breeds having high yielding potential (under the climatic conditions of the area), combined with resistance to diseases is very important.
• For the yield potential to be realized the cattle have to be well looked after – they have to be housed well, should have adequate water, and be maintained disease-free.
• The feeding of cattle should be carried out in a scientific manner – with special emphasis on the quality and quantity of fodder.
• Besides, stringent cleanliness and hygiene (both of the cattle and the handlers; are of paramount importance while milking, storing, and transporting the milk and its products.
• Nowadays, of course, many of these processes have become mechanized, which reduces the chance of direct contact of the product with the handler.
• Ensuring this stringent measurement would, of course, require regular inspections, with proper record keeping. It could also help to identify and rectify the problems as early as possible. Regular visits by a veterinary doctor should be mandatory.

Strategies For Enhancement In Food Production Class 12 NEET Solutions

Improvement Of Livestock:

1. Four Essential Methods For Livestock Improvement: breeding, weeding, feeding, and heeding.
   1. Both the male and female animals selected for breeding should be of superior quality.
   2. Weeding aims that uneconomic animals must be prevented from reproducing.
   3. Feeding is also very important for animals. Each animal should be fed on a balanced ration.
   4. Heeding implies good animal management and general supervision including housing care and maintenance of proper cleanliness and hygiene.
2. Proper health care.
3. Suitable environmental conditions for housing accommodation.
4. Resistance to disease.
5. Regular inspections by veterinary doctors. Three Principle Factors For Productive Potentialities Of Livestock;
   • Genetic make up
   • Nutrition and
   • Environment including the climatic conditions.

Breeds Of Cattle – 26 Indian breeds. The cattle breeds are classified into three groups:

1. Milch Breeds: The cows are good milk-producing bullocks and are of poor quality.
2. Drought Breeds: Bullocks are good for working, and cows are poor milk producers.
3. General Utility Breeds (Dual-Purpose Breeds): Crows are good milk producers, and bullocks are good draught animals.

Some Breeds Of Indian Cattle:

1. Milch Breeds: Gir, Sahiwal, Red Sindhi, Deoni.
2. Drought Breeds: Malvi, Nageri, Hallikar, Kangayam
3. General Utility Breeds: Haryana, Ongole, Kankrej, Tharparkar

New Breeds

1. Karan Swiss: Evolved at the.NDRI, Kamal
   • Breeding between Sahiwal cows with the semen of Brown Swiss bulls imported from the U.S.A.
2. Sunandini: Originated in NDRL Kerala.
   • Cross between the local non-descript cattle with Jersy, Brown Swiss, and Holestein-Friesian breeds.
3. Karan Fries: Evolved at the NDRI, Kamal.
   • Cross between Tharparkar and Holstein Friesian.

Some Exotic Breeds Of Cattle Are Jersy, Holstein-Friesian, Ayrshire, and Brown Swiss

Feeding Cattle: The feed consists of two main components roughage and concentrates.

1. Roughages: Contain high fiber content and include fodder, hay, straw, and silage.
2. Concentrates: Include broken grams, cereals and millets, rice polish, cotton seeds, forage crops, oil cake, oil seeds, and animal by-products.

Strategies For Enhancement In Food Production NEET Important Questions

Indian Buffaloes; Bubalns Bubalis.

• Breeds Of Indian Buffaloes: 7 breeds of buffaloes in India.
  • Good, well-defined milk breeds – Punjab, Rajasthan and Gujrat.
  • Drought breeds – Central and – South India.
• Some Breeds Of Indian Buffaloes: are Murrah, Bhadawari, Jaffrabadi, Surti, Mehsana, Nagpuri, or Ellichpuri, Nili Ravi.

Strategies For Enhancement In Food Production NEET Important Questions

Difference Between Cow And Buffaloes

• Heat period is weaker in buffalo than cows (silent heat).
• Sexual maturity in buffalo bull is later than an ox.
• High calf mortality in buffaloes.
• More annual milk yield.
• Mineral content (Ca, P) is higher in buffaloes.
• Better adaptability, disease resistance, and life span than cows.
• Milk is free from carotenoids.

Uses Of Cows And Buffaloes: Milk, agricultural operations, manure and fuel, leather, meat, hair (for making brushes), bone meal, glue, and gelatin, horns, and hybridization.

Strategies For Enhancement In Food Production NEET Important Questions

Cow And Buffaloes Memory Points

Cow:

• Domesticated animals are used for
  1. Agricultural operations
  2. Milk
  3. Transport
  4. Manure and Fuel
  5. Leather
  6. Glue and Gelatin
  7. Meat.
• The most important breeds of milk cows in the United States are Holstein, Friesian, Jersey, Guernsey, Ayrshire, Brown Swiss, etc.
• There Are 26 Breeds Of Cattle, Classified Into:
• A balanced diet for a cow is rich in carbohydrates, fats, proteins, minerals, vitamins, and water.
• Feeds are divided into roughages and concentrates.
• Roughages contain fibre including hay, fodder, and silage.
• The concentrate mixture is made up of grains and seed by-products.
• The most Common And Nutritious Feed For cats is grasses.
• The Two Breeds – The Karanswiss and Sunandini are developed through cross-breeding at the National Dairy Research Institute, Kamal (Haryana), and in Kerala respectively.

Strategies For Enhancement In Food Production NEET Mcqs With Answers

Buffaloes

• Number of breeds of buffalo in India.
• Indian buffaloes – Bubalis bubalis.
• The average yield of buffalo is 495 kgs. with 6.5 – 7.5 percent fat.
• The average yield of Zebu Cow is 186 kgs. with 4.5 – 5.0 percent fat.
• Sex Vigour in buffalo increases in the colder season.
• The uterine and ovarian cycle of buffalo is 21 days (subject to great variations)
• The duration of heat is 1 to 1 1/2 days.
• On average, the length of gestation is 307 days or 10 months for a buffalo.
• The length of gestation of a cow is 284 days or 9 months.
• Breeding season for buffaloes: September to February.
• Calving season – July to November.
• In buffaloes, the period of lactation is 281 days, the dry period is 139 days, calving interval is 420 days.
• Gastroenteritis is the second highest cause of buffalo calf mortality.
• India possesses the largest number of buffaloes.
• Some important disease-resistant varieties are Zebu Cattle or Bos indicus. They are resistant to Rinderpest, Foot and mouth disease, Anthrax, Black quarter, and Haemorrhagic septicemia.

NEET Biology Strategies For Enhancement In Food Production Animal Breeding

Animal Breeding Aims At:

1. Increasing the quantity of yield.
2. Improving the quality of the produce.

Breeding is of two types Natural breeding and artificial breeding

Inbreeding

• The breeding strategy includes the identification of superior males and females of the same breed and mating them in pairs.
• The progeny of such matings are evaluated and superior males and females are identified for further mating.
• Inbreeding increases homozygosity and thus inbreeding is necessary for evolving a pure line in any animal.
• Inbreeding exposes the harmful recessive alleles, which become eliminated by selection.
• Inbreeding also helps in the accumulation of superior genes and the elimination of less desirable genes.
• However continued inbreeding causes inbreeding depression, which reduces fertility and even productivity.
• Under such a situation the selected animals of the breeding population are mated with unrelated superior animals of the same breed to restore fertility and yield.

Outbreeding: Outbreeding refers to the breeding of unrelated animals either of the same breed or of different breeds or even different species.

Outbreeding is of the following types

1. Outcrossing
   1. Outcrossing is the practice of mating animals of the same breed, but that have no common ancestors on either side of their pedigree up to 4-6 generations.
   2. A single outcross helps to overcome inbreeding depression.
   3. It is the best breeding method for animals that are below average in productivity and growth rate.
   4. Growth rate.
2. Cross-breeding
   1. It is a method of outbreeding in which superior males of one breed are mated with the superior females of another breed of the same species.
   2. This helps in combining the desirable qualities of the two different breeds into the progeny.
   3. The hybrid progeny may be directly used for commercial production or they may be subjected to some form of inbreeding and selection, to develop new stable breeds.
   4. One example of cross-breeding is discardable, a new breed of sheep developed by crossing Bikaneri ewes Marino rams.
3. Interspecific Hybridisation: It is a method of outbreeding in which male and female animals of two different species are crossed to combine the desirable features of both parents into one. for example, the male is produced by a cross between a male donkey and a female horse.

Artificial Insenunalion: It is the process in which the semen collected from a superior male is inserted into the reproductive tract of the selected female by the breeder.

• The advantages of this practice are:
  1. Semen can. be used immediately or stored/frozen and used at a later date when the female is in the right reproductive phase.
  2. Semen can be transported in the frozen form to a distant place where the selected female animals are present.
  3. Semen from one selected male animal can be used on a number of female animals.
• The disadvantage is that the success rate is fairly low.

Strategies For Enhancement In Food Production NEET Revision Notes

Multiple Ovulation Embryo Transfer (MOET): It is a method to improve the herds.

• The steps in the method are as follows:
• A cow is administered hormones (like FSH) to induce follicular maturation and superovulation, i.e., the production of 6-8 ova in one cycle.
• The cow is mated with the selected bull or artificially inseminated.
• The fertilized eggs at 8-32-celled stages are recovered and transferred to surrogate mothers.
• This technology has been used for cattle, rabbits, mares, etc.
• High milk-yielding breeds of females and high-quality meat-yielding bulls have been bred successfully to increase the herd size in a short time.

Sheep

• Breeds of Indian Sheep which do not give any wool – Deccani and Nellore.
• Exotic breeds of sheep are – Dorset, Horn, Suffolk coereidale, or Merino.
• Sheep are most suitable as a class of livestock for utilizing waste lands or weeds from the fields.

Shearing

• Shearing means cutting wool in sheep with shears.
• Shearing is done after the winter or after the rainy season.
• Shearing is done mechanically either with clippers, a pair of scissors, or by a power-operated machine.

Camel-Camelus: There Are Two Types Of Camels

1. One humped – Arabian – Camelus dromidarius
2. Two humped – Bactrian – Camelus bactrianus

Camel found in India – Arabian Adaptations so as to be called the ship of the desert:

1. A thick skin to prevent water loss.
2. Thick foot pads to move on loose, hot sands.
3. Long eyelashes to protect the eye from sand.
4. Hard lips to prevent injury from thorny bushes they browse.
5. Hump – the storehouse of fat.

Indicator of good nutrition in camels – the size of the hump.

• Camels breed in winter (November to March).
• Camels suffer from diseases like – anthrax, pneumonia, camel pox, and surra, e Camels, Llamas, and alpacas are included in one family – camelidae.
• The wt. of camel at maturity is 500-700 kgs. The gestation period of the camels – is 300 days
• Lactation period – 18 months.
• Females produce a calf twice in three years.
• The camels are monooestrous under desert conditions.
• Females mate at the age of 4 years.

Strategies For Enhancement In Food Production NEET Revision Notes

Elephants – Elephas maximum. (Loxodonta Africans)

• Elephants are found in forests with tall trees where bamboos grow in profusion.
• Mean intake varies from 4.2 to 5.6% of the animal’s body weight.
• The daily water consumption of an elephant is 140 – 230 liters.
• Puberty occurs at the age of 8 -12 years.
• The gestation period is 21-22 months.
• The calving interval is 4 years

Pig – Sits Scrofa

• Pig droppings are a good source of nitrogen, phosphorus, and potassium.
• The dominant coat color in pigs is white.
• To feed a pig, maize can be replaced by millet to an extent of 50 percent, similarly, maize can also be replaced by wheat bran and tapioca meal to an extent of 50 percent.
• The marketable body wt. of pigs is 90-95 kgs.

Strategies For Enhancement In Food Production NEET Revision Notes

Domestic horse – Equus caballm

• No. of important Indian breeds is 6.
• Mineral specially added to the diet ofliorscs is a common salt. Donkeys – Eqitus asinu
• Two kinds of donkeys found in India are small grey and large white.
• A large white donkey is found in the Rann of Kutch.

NEET Biology Strategies For Enhancement In Food Production Poultry

It deals with the rearing of fowls, ducks, turkeys, and pheasants for their eggs and meat,

• The average production of an Indian breed is about 60 eggs per annum.
• High-yielding varieties can yield up to 240 eggs per annum.
• The best table bird with plenty of flavored flesh-Aseel.
• Exotic breeds – White leghorn, Rhode Island red, Plymouth rock. New Hampshire, Orpington, Anstrnlorp, Sussex. Minorca.

Poultry: Poultry farming deals with the rearing of fowls (chicken), ducks, turkeys, and pheasants for their eggs and meat. India and the neighboring countries are recognized as the original home of the red jungle fowl (Callus gallus).

• There is evidence that Aseel or Malay fowl were carried to Europe through the Middle East about 2,000 years ago and have given rise to the present-day European breeds.
• Poultry and poultry products are a rich source of animal protein and other nutrients such as fats vitamins and minerals, Consumption of eggs would pave the way for overcoming the protein malnutrition prevalent, especially among children in India.
• Poultry farming has definite advantages over livestock-rearing. Poultry birds are easy to raise, can be acclimatized to a wide range of climatic conditions, have short life spans, and are prolific breeders.
• Hens have an average yield of 60 eggs per year (up to 240 eggs in high-yielding varieties). Poultry farming requires less space is easier to manage and maintain and brings fast returns within a span of six months.
• In a poultry farm, comfortable, well-ventilated, and illuminated, dry houses are built. Birds of different ages the kept in separate houses. In regions with moderate climates, they are kept in cages (coops). The floor is littered with chopped straw, paddy husk, dry leaves, or groundnut hulls.
• It is made rat-proof and provided with water channels with proper drainage. Minerals that are important for poultry diets are calcium, phosphorous, sodium, copper, lo-zinc, iron manganese, and zinc. Vitamins required are vitamin A, D₃,E, and pyridoxine. riboflavin, pantothenic acid, niacin, folic acid B_12, and choline.
• The male breeder’s diet should contain extra calcium, manganese, and vitamin H to ensure proper fertility. Thus a balanced diet is required so that the utilization for building of tissues and egg production is maximised. Clean and fresh water is very much essential for birds.

Light Management:

Illumination is crucial for optimal egg yield. Optimal manufacturing necessitates 14 to 16 hours of light, including natural sunshine.

• When the pullets (young hens, particularly at the onset of egg production) commence laying, provide supplemental lighting if daylight is less than 12 hours.
• Incrementally augment the light duration by 20 minutes each week until a total of 10 hours is achieved.
• A single 40-watt tube light adequately illuminates a 30 sq.m area, whereas a 40-watt bulb is suitable for an 18 sq.m floor area. The illumination must distribute evenly. The illumination should not be sustained during the entire night.

Strategies For Enhancement In Food Production NEET Study Material

Methods For Improvement Of Poultry Farming

• Selection of disease-free suitable breeds.
• The most common egg type variety is single comb while leghorn.
• Meat type variety – Plymouth Rock, Cornish, New Hampshire.

Breeds Of Fowls

• Indigenous Breeds: Aseel, Karaknath, Basara, Briihma, and Cochin.
• Exotic Breeds: White Leghorn, Rhode Island Red, Plymouth Rock, New Hampshire.

Advantage Of Poultry

• Food: Eggs and meat are rich in proteins, minerals fats, and vitamins.
• Economic uplift and employment.
• Birds fecal matter as manure.
• Feathers
• Recreation.
• For food widely distributed as domestic animals, the most common species of jungle fowls are Gulins, gallus, G. Lafayette, and G.sonneratti.
• Poultry feed includes all the nutrients and is made of cereals and millets, oil cake, protein concentrates, fish and meat meal, minerals, and green vegetables.

The domestic fowl (Gallus domesticus) population of our country can be roughly classified into two types:

1. Indigenous (desi type),
2. Exotic (improved type)

Some of the indigenous breeds like Aseel, Karaknath, Ghagus, Brahma, and Busra are the best table birds, The Aseel fowls are used in cock-flighting. The exotic breeds are classified, according to their source of origin, into American class, English class, Mediterranean class, and Asiatic class.

• Some examples are White Leghorn, Rhode Island Red, Plymouth Rock, and New Hampshire. They are now completely acclimatized to Indian conditions. Some of them are excellent egg-layers, whereas others give good meat.
• The indigenous breeds are crossed with exotic breeds to improve egg production. Heterosis has been utilized for producing better egg layers and broilers (birds grown for meat) with high nutritive value.
• Some of the diseases like fowl pox ranikhet, coryza, fowl cholera, and aspergillosis take a heavy toll on poultry. But with better management, proper housing and nutrition, and timely vaccination of the chicks, these diseases can be controlled.
• Ducks comprise 6 percent of the total poultry population in India. They are abundant in the southern and eastern parts of India. There are 20 breeds of duck of which Muscorl, Pekin, Aylesbury, and Campbell are popular exotic breeds. Indigenous breeds include Indian Runner.
• Syhelt meta, etc. Brown and white geese are common in India. Turkeys which are in demand during Christmas time, belong to the breeds Narfold, British White, Broad Breasted Bronze, and Beltsville Small White.

Poultry Diseases

1. Encephalomalacla: The deficiency of vitamin E causes the softening of brain tissue in young poultry.
2. Coccidiosis: The protozoan Eimeria causes coccidiosis in fowls. It causes bloody diarrhea.

Bacterial Diseases

1. Pasteurella – Fowl cholera
2. Salmonella pullorum – Pullorum
3. Mycoplasma gallisepticum – Mycoplasmosis
4. Spirochaete – Spirochaetosis

Aquare: It involves the production of useful aquatic plants and animals such as fishes, prawns, shrimps, lobsters, crabs, and mollusks (edible and pearl oysters) by proper utilization of small and large bodies of water.

• Fisheries: Industry devoted to catching, processing, or selling fish.
  • Fisheries have an important place in the Indian economy. It provides income and employment to millions of fishermen and farmers, particularly in the coastal states. For many, it is the only source of their livelihood.
  • In order to meet the increasing demands on fisheries, different techniques have been employed to increase production. For example, through aquaculture and pisciculture, we have been able to increase the production of aquatic plants and animals, both fresh-water and marine.
  • This has led to the development and flourishing of the fishery industry, and it has brought a lot of income to the farmers in particular and the country in general.
• Aquaculture: Production of useful aquatic plants and animals such as fishes, prawns, shrimps lobster, crabs mollusks, etc.
• Pisciculture: Production of fishes. Fishes are reared in small rivers, ponds, lakes, and canals.

Fish Farming/Fisheries: There are 2 types of fisheries-Inland and Marine fisheries.

Inland Fisheries: Freshwater: Cultivation in rivers, canals, reservoirs lakes, ponds, and tanks.

Brackish Water: Estuaries, Lagoons, reservoirs.

Types Of Ponds: 3 types of ponds are required for Indian major carp.

Strategies For Enhancement In Food Production NEET Study Material

Nursery Ponds

• Receive tender hatching and spawn.
• Small and seasonal nurseries are preferred.
• Production of zooplankton to serve as food for the spawn.

Rearing Ponds: Fries (young fish) are collected from nursery ponds and released into rearing ponds to develop in fingerlings

Stocking Ponds: Fingerlings are transferred from rearing to stocking ponds, where they develop into adult fish and are kept for stocking.

Types Of Breeding

1. Natural Breeding/Bundh Breeding: Breading is done in natural bundhs, a special type of ponds formed by the accumulation of large quantities of rainwater in a low-lying area, and natural conditions are provided with exits also.
2. Artificial Breeding: Sperm from males and ova from females are collected and fertilization is done in in-vitro conditions.
   • Hormone gonadotrophins are also used. FSH and LH secreted by the pituitary, influence the maturation of gonads and spawning in fish.

Composite Farming: Selected species of fish are stocked together in proper proportion to increase fish production many times.

Compatible species do not harm each other, example, Catla catla (surface feeder), Labeo-rohita (Column feeder), and Cirrhinus mrigtila (bottom feeder) are used for composite farming. Some edible freshwater fishes.

• Rohu – Labeo-rohita
• Calbasu – L. Calbasu
• Catla – Catla catla
• Mirgal – Cirrhinus mrigala
• Magur – Clarius
• Common carp

Marine Fisheries: Fishery aspect of seawater of the ocean. A recent survey revealed abundant resources of sardines and mackerel on the southwest coast. Fishing trawlers fitted with sophisticated electronic fish-locating equipment have also been introduced to give a fillip to deep-sea fishing.

Integrated Fisheries project located at Cochin engaged in the exploration and utilization of marine resources in S.W. India.

Strategies For Enhancement In Food Production NEET Study Material

Edible Marine Fishes

• Eel – Anguilla
• Hilsha – Hilsa
• Pomphret – Stromateus
• Salmon – Aluitheronema
• Bombay duct – Harpodon
• Sardine – Sardinella
• Mackeral

Marine Fishes Use/Importance

• Fish as food
• Fish for controlling disease: Larvivorous (gambusia).
• Scientific value: Lung fishes of importance.
• Aesthetic value: Aquarium fishes, Macropodus, Carassius (goldfish), pterophyllum (angel fish), and Betta (fighting fish).
• Fish product: Fish oil
• Fish glue: Sticky product obtained from the skin of cod.
• Isinglass: Gelatinous substance from the air bladder of perches, Indian salmon used in the preparation of special cement and in clarification of wine and beer.
• Shagreen: Skin of sharks and rays used in polishing wood and other materials as well as for covering jewelry boxes and swords.
• Leather and artificial pearls (from silver bony scales of cyprinids
• Employment.

Pisciculture production of fishes.

• Seed fish are produced by aquaculture techniques of induced breeding by administration of pituitary hormones.
• Fish is a valuable food source of proteins.
• India is among the six foremost seafood-producing nations in the world.
• Fresh water includes the country’s great river systems, an extensive network of irrigation canals, reservoirs, lakes, tanks, ponds, etc.
• Brackish water includes estuaries, lagoons, and mangrove swamps.
• An Integrated fishery project located at Cochin is engaged in the exploration and utilization of marine resources and is the biggest of its kind in Southeast Asia.
• Inland fisheries provide 40% of total fish production.

NEET Biology Strategies For Enhancement In Food Production Apiculture or Beekeeping

Beekeeping or apiculture is the maintenance of hives of honeybees for the production of honey. It has been an age-old cottage industry.

Common Species Of Honey Bee: Apis mellifera, Apis indica, Apis dorsata, Apis florea. Social Organisation: Good and well-developed honeycomb. 40-50 thousand individuals.

Social Organization (Castes) Of Honey Bee: The nest of the honey bee is known as the bee hive. The hive consists of 32 to 60 thousand individuals, showing a highly organized division of labor in the colony. Bees are polymorphic, consisting of three types of individuals (Castes) viz, QUEEN, DRONE, and WORKER. The characters are given in the following table.

Honey is a food of high nutritive value and also finds use in the indigenous system of medicine.

• It is composed of levulose, dextrose, maltose and other sugars, enzymes and pigments, ash, water, vitamins and minerals.
• Honey produced by the honey bee Apis species is probably the oldest sweetening agent in our civilization. Honey contains two sugars – dextrose and levulose – and a mixture of several other substances. It is tasty, health-giving, and also medicinally useful.

Honeybees also yield wax, which has multiple uses. A large quantity of honey is still collected from wild sources. However, bee-keeping (apiculture) using domesticated bees has been practiced in many parts of the world, including India (using A. dorsata, A. florea, and A. indica).

• From its mandibular gland, the developing queen secretes a queen substance. It inhibits the worker bees from building brood chambers for future queens. Honeybee also produces beeswax, which finds many uses in industry, such as in the preparation of cosmetics and polishes of various kinds.
• The increased demand for honey has led to large-scale beekeeping practices; it has become an established income-generating industry, whether practiced on a small or on a large scale.

Strategies For Enhancement In Food Production NEET Question Bank

Bee Diseases

• Pebrine – N.apis,
• Paralysis dysentery
• Acarine disease – Acarapis wood

Bee-keeping: It can be practiced in any area where there are sufficient bee pastures of some wild shrubs, fruit orchards, and cultivated crops. There are several species of honeybees that can be reared. Of these, the most common species is Apis indica. Beehives can be kept in one’s courtyard, on the verandah of the house of even on the roof. Beekeeping is not labor-intensive.

For Successful Bee-keeping

• Knowledge of nature and habits of honey bees.
• Selection of suitable locations for keeping bee hives.
• Catching and hiving of swarms.
• Management beehives during summers
• Handling and collection of honey and bee wax.

Bee Communication: Karl van Frisch (1946-69: Awarded Nobel prize for decoding the language of honey bees. Bee performs two types of dance

Round Dance: Food source is within 75 m.

Strategies For Enhancement In Food Production NEET Question Bank

Tail Wagging Dance/Waggle Dance: Food is more than 75 m away.

Bees are the pollinators of many of our crop species (see concerned chapter) such as sunflower, Brassica, apple, and pear. Keeping beehives in crop fields during the flowering period.

Apiculture: Science of rearing bees for economic value,

Strategies For Enhancement In Food Production NEET Question Bank

• Types Of Honey Bees;
  1. Apis indica (Indian bee)
  2. Apis mellifera (Italian bee)
  3. Apis dorsata (Rock bee)
  4. Apis florea (Little bee)
• Most Important And Useful Bee – Apis Mellifera
  • Worker bees are immature, sterile females.
  • The compartments of honeycomb are called cells and are divided by thin plates of wax.
  • The foundation to build honeycombs is provided by a comb foundation – a wax sheet.
  • Honeybees are reared in apiaries
  • Apis dorsata is the main source of bee wax.
  • Sugars in honey are glucose, fructose, and levulose.

Silkworms Sericulture: The science of rearing silkworms for producing silk.

Main cottage industry of silk – China, Japan, India, and some European countries.

Silkworms Life Cycle: Egg Larva → Pupa → Adult

Silk Extraction

• After one or two days of cocoon formation pupa are either killed by boiling or drying in the Sun.
• The raw silk fibers from the cocoon are then reeled into silk thread.
• Pupa are killed before they emerge into adulthood as the long silk fibers are broken and can thin and only be spun like cotton can not reel.
• Few cocoons or seeds are kept to develop into adults to continue generation.

Silk Extraction Important Points

• Composition of silk.
• Protein fibroin (75 – 80%) and Sericin (20 – 25%)
• The intestine of silkworm – Gut, used in fishing and some surgical work.
• Bombyrmori: China silk worm – Mulberry silk – Best silk.
• The disease of the silkworm is Pebrine caused by Nosema bombycis.
• Silkworm Bombyx mori is reared on mulberry leaves.
• Caterpillars are very active feeders.
• The hard covering of silk fibers around the worm is called a cocoon, A silkworm with a cocoon is known as a pupa.
• Pupae are killed to get silk thread because the emergence of an adult breaks the thread.

NEET Biology Strategies For Enhancement In Food Production Lac Culture

The zoological name of the lac insect is Laccifer lacca or Tachardia lacca.

• Lac insect belongs to the order Homoptera.
• Lac is a resinous substance secreted from the hypodermal glands of the body of the larval stage and females.
• Lac insects usually build lac houses for the protection of host plants like Butea monosperma (palas), Shorea robusta, (sal), Acacia nilotica (Babul), Mangifera indica (mango), etc.
• Male and female insects live separately in lac capsules
• After copulation male dies, female lays about 200-300 eggs.
• The larvae (nymphs) are red-colored and suck the plant sap by boring the tender twigs.
• The secretion of the lac glands covers the body of the insect, it joins the cover of the insect with a twig of tree.

Strategies For Enhancement In Food Production NEET Question Bank

Lac Culture Uses

1. Lac in the form of shellac is used as sealing material.
2. Lac is also used in the printing industry, preparation of gramophone records, electrical appliances, varnish, polish paints, toys, bangles, buttons cosmetics, etc.

Hybrid Breeds Of Livestock. Karanswiss was developed at NDRI Kamal while Sunandini was developed at NDRI Kerala.

Broiler. Chicken reared for meat.

Fish Gauno. Dried refuse after extraction of oil.

Honey is aromatic, viscid, and sweet-material. The color and flavor of honey depend upon the source of nectar.

The Honey consists of:

• Fish Liver Oil. It is extracted from the liver of fish. It is the main source of Vitamin-A though the liver oil of some fishes also contains vitamins C, D, and E. For example, the liver oil of certain fishes like Tuna, Halibut, etc. is rich in vitamin D.
  • Vitamin- E (a-tocopherol) acts as an anti-oxidant of vitamin A. Cod liver oil contains about 60-75% of oil contents but a low percentage of vitamin A, while Tuna and Halibut liver oil contain a lower (4 to 28%) percentage of oil Fut higher percentage of vitamin -A.
• Fish Protein. It is in the form of white powder extracted from fish wastes by removing the fat and contains 80 to 90% soluble proteins. It is used in the preparation of ice cream, pharmaceuticals, paints, varnishes, textiles, paper, and cosmetics.
  • Fish Protein Concentrate (FPC) has been defined as a stable product prepared from whole fish or parts thereof, by the removal of water and, in certain cases, oil, bones, and other materials.
• Milk Yield/Cow/Yr. 4250 kg in the U.S.A. and 220 kg in India. Tassar Silk. Besides Anthenea roylei, other species are A- paphia, A. perenyi, and A. mylitta.
• Arnadi Silk is obtained from the cocoon of the Eri silkworm—Altacus ricin
• Muga Silk is obtained from cocoons of muga silkworm Anthenea assama.
• Pashmina. Under the fur of Kashmiri goat
• Angoora Wool. From Angoora rabbit.
• An insecticide used to control external parasites, like lice on cattle is lindane.
• Yak – Lahaul Spiti, Leh, Ladhakh, Garhvval, Sikkim

NEET Biology Strategies For Enhancement In Food Production Synopsis

Animal Husbandry. Agricultural practice of breeding and raising livestock like buffaloes, cows, pigs, horses, cattle, sheep, camels, goats etc. It also includes poultry farming and fisheries.

Strategies For Enhancement In Food Production NEET Question Bank

Dairy Farm Management: Management of animals for milk and its products

• Selection of high-yielding breeds.
• Resistance to diseases
• Cleanliness and hygienic shelter
• Regular inspection
• Proper record
• Quality and quantity of fodder
• Water
• Milking, storage of milk and products.

Poultry Farm Management

• Management of domesticated fowls (birds) used for food and eggs.
• All facts about dairy farm management + Eradication dispersing of vims affected birds.

Apiculture (Beekeeping Maintenance of hives of honey bees for obtaining honey and wax.

• Successful bee-keeping
• Knowledge of nature and habits of bees
• Selection of suitable location for keeping beehives.
• Catching and hiving of swarms.
• Management of beehives during different seasons.
• Handling and collection of honey and of bees wax.

Fisheries. Catching, processing, selling of fish, and shellfish or other aquatic animals;

• Freshwater fishes
• Catla, Rohu and Carps
• Marine fishes
• Hilsa, Sardine, Mackerel Pomffet

Enhancement In Food Production MCQ For NEET Biology

Question 1. Maximum contrilnilion to the total milk production of our country comics from:

1. Cows
2. Buffaloes
3. Camels
4. Goat.

Answer: 2. Buffaloes

Question 2. Murrah is a breed of:

1. Cow
2. Sheep
3. Buffaloes
4. Goat

Answer: 3. Buffaloes

Question 3. Lac is a:

1. Plant product
2. Mineral product
3. Synthetic product
4. Animal product.

Answer: 4. Animal product.

Question 4. Aquaculture includes:

1. Freshwater fishing
2. Brackish water fishes
3. Marine fishery
4. All of the above.

Answer: 4. All of the above.

Read and Learn More NEET Biology Multiple Choice Question and Answers

Enhancement of Food Production MCQs Question 5. Which of the following species is specially domesticated and reared for high economic importance?

1. Apis indica
2. Apis mellifera
3. Apis dorsata
4. Apis florea.

Answer: 1. Apis Indica

Question 6. Cryopreservation is:

1. Preservation of living beings in chemicals
2. Preservation at very low temperature
3. Preservation through exposure to irradiation
4. Preservation at high temperature.

Answer: 2. Preservation at very low temperature

Question 7. Cryopreservation is useful for:

1. Preservation of semen
2. Very young fetuses
3. Living cells and body parts
4. All the above.

Answer: 4. All the above.

Question 8. Exotic breeds:

1. Require specific environment
2. Hardy and high-yielding
3. Are sturdy
4. Take less food.

Answer: 1. Require specific environment

Enhancement of Food Production MCQs Question 9. Exotic breeds are:

1. Used for cross-breeding
2. Allowed to multiply and replace local breeds
3. Easy to manage
4. Resistant to local pests and pathogens.

Answer: 1. Used for cross-breeding

Question 10. Infertility of local breeds of cattle can be overcome by the use of:

1. Cross-breeding with exotic breeds
2. Good nourishment
3. Stilbesterol
4. Gonadotropin.

Answer: 4. Gonadotropin.

Question 11. Stilbesterol is used for:

1. Induction of lactation
2. Artificial insemination
3. Super-ovulation
4. Cryopreservation.

Answer: 1. Induction of lactation

Question 12. A surrogate mother is:

1. Mother without lactation
2. Future mother with embryo implanted from another
3. Carrying several embryos at one time
4. Artificially inseminated female

Answer: 2. Future mother with embryo implanted from another

Question 13. Artificial insemination is better than natural insemination in cattle because

1. Semen of good bulls can be provided everywhere
2. There is no likelihood of contagious diseases
3. It is economical
4. All the above.

Answer: 4. It is economical

Enhancement of Food Production MCQs Question 14. A milch breed of cow is:

1. Haryana
2. Malvi
3. Kankrcj
4. Hallikcr.

Answer: 1. Haryana

Question 15. A draught breed of cattle is:

1. Red Sindhi
2. Gir
3. Malvi
4. Haryana.

Answer: 3. Malvi

Question 16. An exotic breed of cow is:

1. Ongolc
2. Friesian
3. Hallikcr
4. Deoni.

Answer: 2. Friesian

Question 17. Hybrid breed of cattle is:

1. Sunandini
2. Holstein
3. Brown Swiss
4. Kankrcj.

Answer: 1. Sunandini

Question 18. The gestation period for buffalo is:

1. 9 months
2. 14 months
3. 10 months
4. 21-22 months.

Answer: 3. 10 months

Question 19. Cows and buffaloes remain in heat for:

1. 24-36 hours
2. 36-48 days
3. 7-10 days
4. 15-20 days.

Answer: 1. 24-36 hours

Enhancement of Food Production MCQs Question 20. Bhutia is a breed of:

1. Chicken
2. Goat
3. Sheep
4. Horse.

Answer: 4. Horse

Question 21. Ship of the desert is:

1. Elephant
2. Camel
3. Sheep
4. Goat.

Answer: 2. Camel

Question 22. The animal most useful on difficult terrain

1. Mule
2. Yak
3. Camel
4. Elephant.

Answer: 1. Mule

Question 23. Bactrian camel is characterized by:

1. Two humps and a long neck
2. Two humps and long limbs
3. Two humps and a thick coat
4. Single hump and thick coat.

Answer: 3. Two humps and a thick coat

Strategies for Enhancement in Food Production MCQ Question 24. A beast of burden that needs little care is:

1. Pig
2. Donkey
3. Mule
4. Yak.

Answer: 2. Donkey

Question 25. The largest land animal is:

1. Camel
2. Elephant
3. Rhino
4. Python.

Answer: 2. Elephant

Question 26. Elephants are sought after for:

1. Skin
2. Hair
3. Meat
4. Ivory.

Answer: 4. Ivory.

Question 27. The earliest animal to be domesticated was:

1. Goat
2. Dog
3. Horse
4. Cat.

Answer: 2. Dog

Question 28. The most used domesticated animal by Eskimos is:

1. Cow
2. Sheep
3. Goat
4. Husky.

Answer: 4. Husky.

Strategies for Enhancement in Food Production MCQ Question 29. Huskies are:

1. Yaks
2. Donkeys
3. Thick coated dogs
4. Water buffaloes.

Answer: 3. Thick coated dogs

Question 30. The best source for dietary protein for a vegetarian is:

1. Soya Bean
2. Gram
3. Groundnut
4. Milk.

Answer: 4. Milk.

Question 31. Zebu cattle are:

1. Water Buffalo
2. Indian Buffalo
3. Cow
4. Sheep

Answer: 3. Cow

Question 32. Cow Water Buffalo is

1. European breed of buffalo that prefers living in water for most of the day
2. Buffalo-like animals living in rivers
3. Llama
4. Buffalo.

Answer: 4. Buffalo.

Question 33. Which is the real product of Honey bee:

1. Honey
2. Pollen
3. Beeswax
4. Propolis.

Answer: 3. Beewax

Strategies for Enhancement in Food Production MCQ Question 34. The hatching net is called:

1. Nursery kind
2. Production pond
3. Stocking pond
4. Hapa.

Answer: 4. Hapa.

Question 35. Spawning in fishes can be induced by:

1. TSH
2. Thyroxine
3. FSH and LH
4. STH.

Answer: 3. FSH and LH

Question 36. The percentage of proteins in the fish meal is:

1. 15-20%
2. 25-50%
3. 40-50%
4. 55-70%.

Answer: 4. 55-70%.

Question 37. The rearing and breeding of fish in ponds, tanks, and artificial reservoirs are called

1. Aquaculture
2. Fishing
3. Pisciculture
4. Apiculture.

Answer: 3. Pisciculture

Question 38. Composite fish farming is called

1. Polyculture
2. Pisciculture
3. Monoculture
4. None of these.

Answer: 1. Polyculture

Strategies for Enhancement in Food Production MCQ Question 39. Pisciculture has a bright future in India due to:

1. Considerable demand
2. Good response of native fishes to culture
3. Abundance of cultivable waters
4. All of these.

Answer: 4. All of these.

Question 40. Silk, honey, and lac are:

1. Secretory substances of insects
2. Secretory substances of plants
3. Artificial chemicals
4. All of the above.

Answer: 3. Artificial chemicals

Question 41. Match the terms in Column A with suitable terms in Column B.

1. (1—D) (2—F), (3—G), (4—C), (5—A), (6—B), (7—E)
2. (1—D). (2—F), (3—A), (4—C), (5—B), (6—E), (7—C)
3. (1—D), (2-F), (3—A), (4—G), (5—C), (6—B), (7—E)
4. (1—D), (2—F), (3—G), (4—C), (5—B), (6—A), (7—E)

Answer: 3. (1—D), (2-F), (3—A), (4—G), (5—C), (6—B), (7—E)

MCQs on Enhancement of Food Production Question 42. The draught breeds of cattle include:

1. Malvi, Nageri and Hallikar
2. Malvi, Nageri and Ongole
3. Nageri, Ongole and Haryana
4. All the above.

Answer: 1. Malvi, Nageri and Hallikar

Question 43. The method maximum used in cattle breeding is:

1. Random breeding
2. Artificial insemination
3. Controlled breeding
4. Superovulation and embryo transplant.

Answer: 2. Artificial insemination

Question 44. Rinderpest is the disease of:

1. Cattle
2. Poultry
3. Fish
4. Camel.

Answer: 1. Cattle

Question 45. Which of the following countries has the maximum average annual milk yield per cow?

1. United Kingdom
2. U.S.A.
3. Denmark
4. India.

Answer: 2. U.S.A.

Question 46. Which of the following countries has a minimum average annual milk yield per cow?

1. India
2. Pakistan
3. Netherlands
4. England.

Answer: 1. India

Question 47. Which of the following diseases in poultry is caused by nutritional deficiency?

1. Perosis
2. Fowl pox
3. Coryza
4. Aspergillosus.

Answer: 1. Perosis

MCQs on Enhancement of Food Production Question 48. Ranikhet or New Castle Disease ‘of poultry is caused by:

1. Bacteria
2. Virus
3. Fungus
4. None of these.

Answer: 2. Virus

Question 49. The animal close to human beings which is cloned by an American scientist Dr. Don Wolf 1996 is:

1. Gorilla
2. Chimpanzee
3. Gibbon
4. Monkey.

Answer: 4. Monkey.

Question 50. Ambergris is the secretion from the intestine used in the manufacture of perfumes and other cosmetics:

1. Tachyglossus- Echidna
2. Physeter-Sperm whale
3. Musk-Deer
4. Kangaroo-Macropus.

Answer: 2. Physeter-Sperm whale

Question 51. Parthenogenesis is commonly round in:

1. Ants, boos, and wasps
2. Ascaris, oarlliwonn, and liver fluke
3. Frogs, fishes, and foxes
4. Starfish, Jellyfish, and cuttlefish.

Answer: 1. Ascaris, oarlliwonn, and liver fluke

Question 52. The length of silk fiber which surrounds a cocoon is about:

1. 800 to 1200 yards
2. 8000 to 12000 yards
3. 800 to 1200 feet
4. 8000 to 12000 meters.

Answer: 1. 800 to 1200 yards

MCQs on Enhancement of Food Production Question 53. The technique of silk production from the cocoons of silkworms was first known to:

1. India
2. China
3. United Kingdom
4. U.S.A.

Answer: 2. China

Question 54. Maximum cocoon and raw silk production is in:

1. China
2. Japan
3. U.S.S.R.
4. Brazil.

Answer: 1. China

Question 55. Central Silk Research and Training Institute (CSRTI) is located at:

1. Assam
2. Bahrampur
3. Tarai region
4. Shanthivials (Mysore).

Answer: 4. Shanthivials (Mysore).

Question 56. Most commercial silkworm strains are:

1. Uni-voltine
2. Vi-colline
3. Multi-volcanic
4. All of these.

Answer: 2. Vi-colline

MCQs on Enhancement of Food Production Question 57. The larval form of the silk moth is called:

1. Naiad
2. Maggot
3. Caterpillar
4. Wriggler.

Answer: 3. Caterpillar

Question 58. Eri silk is produced by:

1. Bombyx mori
2. Atticus ricin
3. Anthenea roylre
4. Anthenea paphia.

Answer: 2. Attcicus ricin

Question 59. Passive, non-locomotory, and non-feeding stages in the life history of the Silk moth are:

1. Caterpillar
2. Imago
3. Nymph
4. Pupa.

Answer: 4. Pupa.

Question 60. Nosemia sp. a protozoan produces diseases in:

1. Silk moth
2. Honey bee
3. Both silk moth and honey bee
4. Lac insect.

Answer: 3. Both silk moth and honey bee

NEET Biology Strategies for Enhancement in Food  Question 61. Which type of silk is obtained from Bombyx mori?

1. Reeled silk
2. Muga silk
3. Arandi silk
4. Tasar silk.

Answer: 1. Reeled silk

Question 62. Silk glands of silkworms are modified:

1. Crop glands
2. Salivary glands
3. Gastric glands
4. Intestinal glands

Answer: 2. Salivary glands

Question 63. Hinny Finny is a crossbreed between

1. Male donkey and female horse
2. Female donkey and male horse
3. Male mule and female horse
4. None of these.

Answer: 2. Male mule and female horse

Question 64. Match the terms of Column A with suitable terms in column B.

1. (1-C), (2-B), (3-E), (4-D), (5-A)
2. (1—C), (2—A), (3—E), (4—D), (5-B)
3. (1—C), (2—A), (3—E), (4—B), (5—D)
4. (1—E), (2—E), (3—B), (4—A), (5—D).

Answer: 3. (1—C), (2—A), (3—E), (4—B), (5—D)

NEET Biology Strategies for Enhancement in Food  Question 65. Poultry includes:

1. Fowl, duck, tortoise, and turkey
2. Fowl, duck, pigeon, and tortoise
3. Duck, fowl, tortoise and turtle
4. Fowl, duck, turkey, and pigeon.

Answer: 4. Fowl, duck, turkey, and pigeon.

Question 66. The percentage of proteins in the egg white is:

1. 12%
2. 35%
3. 64%
4. 70%.

Answer: 3. 64%

Question 67. The main protein type found in egg white is:

1. Ovalbumin
2. Canalbumin
3. Phosvitin
4. Lipovitellin.

Answer: 1. Ovalbumin

Question 68. Central Food Technological Research Institute is located at:

1. Izatnagar
2. Lucknow.
3. Dehradun
4. Mysore.

Answer: 4. Mysore

Question 69. Which one of the following is our indigenous breed of chicken?

1. Plymouth Rock
2. White Leghorn
3. Aseel
4. Rhode Island Red.

Answer: 3. Aseel

NEET Biology Strategies for Enhancement in Food  Question 70. A hybrid variety produced, having more meat-producing capacity, in chickens is:

1. Broilers
2. Plymouth rock
3. White Romish
4. New Hemisphere.

Answer: 1. Broilers

Strategies For Enhancement In Food Production Animal Sources Questions From Competitive Examinations

Question 1. Which of the following lias have been recently used for increasing the productivity of super milk cows:

1. Artificial insemination by a pedigree bull only
2. Superovulation of a high-production cow only
3. Embryo transplantation only
4. A combination of superovulation, artificial insemination, and embryo transplantation into a carrier cow (surrogate mother).

Answer: 4. A combination of superovulation, artificial insemination, and embryo transplantation into a carrier cow (surrogate mother).

Question 2. The name of the sheep that was cloned for the first time is:

1. Dolly
2. Polly
3. Molly
4. Holly.

Answer: 3. Molly

Question 3. Inland fisheries is referred to as:

1. Culturing fish in freshwater
2. Trapping and capturing fish from seacoast
3. Deep sea fishing
4. Extraction of oil from fish.

Answer: 1. Culturing fish in freshwater

Question 4. On the basis of utility. Nagapuri buffaloes are categorized as:

1. Grazers
2. Dual purpose
3. Draught cattle
4. Milkers.

Answer: 4. Milkers.

Question 5. Natural silk contains:

1. Potassium
2. Phosphorus
3. Nitrogen
4. Magnesium.

Answer: 3. Nitrogen

Enhancement of Food Production MCQs Question 6. In India the best aquarium is located at:

1. Z.S.I. Kolkata
2. Tarapur, Mumbai
3. Chennai
4. Vishakhapatnam.

Answer: 2. Chennai

Question 7. Pearl oyster belongs to class:

1. Gastropoda
2. Pelecypoda
3. Scaphopoda
4. Amphineura.

Answer: 2. Pelecypoda

Question 8. Lac is produced as:

1. Feces of lac body
2. Secretion from body
3. Excretion from body
4. Excess from oozing out of the body.

Answer: 2. Secretion from body

Question 9. Which one is the best silk?

1. Eri silk
2. Mulberry silk
3. Tasar silk
4. None of the above.

Answer: 2. Mulberry silk

Question 10. Lac is produced from

1. Only males
2. Only females
3. More females than males
4. More males than females.

Answer: 2. Only females

Enhancement of Food Production MCQs Question 11. The silkworm spins its cocoon:

1. From inside to outside
2. Outside to inside
3. Random
4. Inside.

Answer: 2. Outside to inside

Question 12. The three major carps. -Cattle, Labeo, and Cirhinus grown in the same pond are due to:

1. There is no competition among them for food material
2. Their feeding habits are different
3. They live in different habitats
4. None of the above.

Answer: 1. There is no competition among them for the food material

Question 13. The Indian tiger prawn is:

1. Pennons implicit
2. Penacus monodon
3. Macrobradmm
4. Palaemon.

Answer: 2. Penacus monodon

Question 14. Shagreen is obtained from:

1. Dried skin of shark
2. Skin of codfish
3. Air bladder of fishes
4. None of the above.

Answer: 1. Dried skin of shark

Question 15. Ishingless is obtained from:

1. Liver of frog
2. Scales of fishes
3. Air bladder of fishes
4. The skin of a shark.

Answer: 3. Air bladder of fishes

Question 16. Lac is:

1. Excretion of lac insect
2. Dead body of lac insect
3. Body secretion of lac insect
4. None of the above.

Answer: 3. Body secretion of lac insect

Question 17. It is now possible to breed plants and animals with desired characteristics through:

1. Ikebana technique
2. Tissue culture
3. Genetic Engineering
4. Chromosome Engineering.

Answer: 3. Genetic Engineering

Question 18. The large distribution of clean quality milk all the world over can be said to be due to the great work of:

1. Robert Koch
2. Leeuwenhoek
3. Louis Pasteur
4. Blackman.

Answer: 3. Louis Pasteur

Enhancement of Food Production MCQs Question 19. In lac insect, lac is produced from:

1. Abdominal glands
2. Salivary glands
3. Skin glands of the abdomen
4. None of the above.

Answer: 3. Skin glands of the abdomen

Question 20. The honey bees exhibit a type of dance to communicate the location of food. This is known as:

1. Tap dance
2. Round dance and waggling dance
3. Breakdance
4. Waggle dance.

Answer: 4. Waggle dance.

Question 21. Arhenotoky is a type of:

1. Parthenogenesis found in honey bees, wasps and ants
2. Parthenogenesis found in every insect
3. Parthenogenesis found in mosquitoes
4. Parthenogenesis is found in butterflies.

Answer: 1. Parthenogenesis found in honey bees, wasps and ants

MCQs on Enhancement of Food Production Question 22. Which among the following is the real product of honey bees?

1. Pollen
2. Bee wax
3. Honey
4. Propolis.

Answer: 4. Propolis

Question 23. Which one of the following is the source of silk?

1. Eggs
2. Caterpillar
3. Cocoon
4. Pupa.

Answer: 3. Cocoon

Question 24. Which one of the following mollusca groups is primarily used in the pearl formation?

1. Monoplacophorans
2. Cephalopods
3. Gastropods
4. Pelecypods.

Answer: 4. Pelecypods.

Question 25. The main composition of lac is:

1. Glue, pigment, and sugar
2. Wax, pigment, and glue
3. Resin, pigment, wax, and glue
4. Resin, sugar, and wax.

Answer: 3. Resin, pigment, wax, and glue

MCQs on Enhancement of Food Production Question 26. The main product of poultry is:

1. Eggs
2. Chicken
3. Meat
4. Eggs and meat.

Answer: 1. Eggs

Question 27. The insect that is not found in the wild state is:

1. Lac insect
2. Cochineal insect
3. Honey bee
4. Silk moth.

Answer: 2. Cochineal insect

Question 28. The scientific name of the lac insect is:

1. Tachardia lacca
2. Bombyx mori
3. Cimex lectularis
4. Pediculus pithiris.

Answer: 1. Tachardia lacca

Question 29. The milch breeds of cattle are?

1. Mallikar, Nageri and Malvi
2. Gir, Sahiwal and Deoni
3. Kankrej, Haryanna and Ongole
4. Tharparkar and Kangayam.

Answer: 2. Gir, Sahiwal and Deoni

Question 30. Common wild rock honey bees are:

1. Apis mellifera
2. Apis indica
3. Apis dorscita
4. None of the above.

Answer: 3. Apis dorscita

Question 31. The tassar silk moth belongs to the family:

1. Bombycidae
2. Stumidae
3. Hymenoptera
4. Diptera.

Answer: 2. Stumidae

Question 32. The Indian carp is:

1. Scoliodon
2. Labeo
3. Torpedo
4. Pristis.

Answer: 2. Labeo

Question 33. Gambusia is a:

1. Predator on mosquito larvae
2. Pest of fishes
3. Parasite on crab
4. Pathogenic protozoan.

Answer: 1. Predator on mosquito larvae

NEET Biology Strategies for Enhancement in Food  Question 34. Silk glands are modified:

1. Salivary glands
2. Anal glands
3. Colleterial glands
4. Mushroom glands.

Answer: 1. Salivary glands

Question 35. The largest silk-producing state of India is:

1. Karnataka
2. Bihar
3. Assam
4. West Bengal.

Answer: 1. Karnataka

Question 36. Pearl-producing Indian species are:

1. Pinctada indica
2. Ostrea indica
3. Pinctada vulgaris
4. Ostrea vulgaris.

Answer: 3. Pinctada vulgaris

Question 37. The world’s highly prized wool-yielding ‘Pashmina breed’ is:

1. Sheep
2. Goat
3. Goat-sheep cross
4. Kashmir sheep-afghan sheep cross.

Answer: 2. Goat

Question 38. Match the breeds of cattle given under Column A with the place of their origin listed under Column B. Choose the answer that gives the correct combination of alphabets of the two columns.

1. 1 = B, 2 = D, 3 = E. 4 = A
2. 1 = D, 2 = C, 3 = E, 4 = A
3. 1 = B, 2 = D, 3 = A, 4 = E
4. 1 = D, 2 = E, 3 = A, 4 = C.

Answer: 2. 1 = D, 2 = C, 3 = E, 4 = A

Question 39. Which of the following is the sequence of cultivation of fish?

1. Fry—fingerlings—spawn—Adult
2. Spawn—fry—fingerlings—adult
3. Adult—spawn—fingerlings—fry
4. Fingerlings—fry—spawn—adult.

Answer: 3. Adult—spawn—fingerlings—fry

NEET Biology Strategies for Enhancement in Food  Question 40. The amount of protein per 100 g (without water, approximately 2 eggs) is:

1. 11.9
2. 20.1
3. 16
4. 45

Answer: 2. 20.1

Question 41. MOET is a method of:

1. Fish cultivation
2. Cloning in sheep
3. Hybridization in cattle
4. Birth control in humans

Answer: 3. Hybridization in cattle

Question 42. When a cross is made between two species of the same genus, then the cross is known as

1. Intraspecific hybridization
2. Interspecific hybridization
3. Intergeneric hybridization
4. Intervarietal hybridization.

Answer: 2. Interspecific hybridization

Question 43. Which one of the following types of silk is being produced extensively in South India?

1. Eri
2. Mulberry
3. Tussar
4. Muga.

Answer: 3. Tussar

Question 44. Mating between two individuals differing in genotype produces a genetic variation called

1. Domestication
2. Incubation
3. Hybridization
4. Mutation.

Answer: 3. Hybridization

Question 45. Which of the following organisms is useful for us?

1. Musca
2. Bombyx
3. Pheretima
4. Periplaneta.

Answer: 2. Bombyx

Question 46. Which of the statements about breeding is wrong?

1. By inbreeding purelines cannot be evolved.
2. Continued inbreeding, especially close inbreeding reduces fertility and productivity.
3. Cross-breeding allows the desirable qualities of two different breeds to be combined.
4. Inbreeding exposes harmful recessive genes that are eliminated by selection.
5. A single outcross often helps to overcome inbreeding depression.

Answer: 2. Continued inbreeding, especially close inbreeding reduces fertility and productivity.

Question 47. Compared to a bull a bullock is docile because of:

1. Higher levels of cortisone
2. Lower levels of blood testosterone
3. Lower levels of adrenalin/noradrenalin in its blood
4. Higher levels of thyroxine.

Answer: 2. Lower levels of blood testosterone

NEET Biology Gene Expression And Gene Regulation

NEET Biology Gene Expression

It is the mechanism at a molecular level by which a gene can express itself in the phenotype of an organism. The mechanism of gene expression involves biochemical genetics.

• It consists of the synthesis of specific RNAs, polypeptides, structural proteins, proteins biochemicals such as enzymes.
• DNA is the master molecule that directs gene expression.

NEET Biology Gene Expression And Gene Regulation Operon Concept

Francois Jacob and Jacques Monod, in 1%1, proposed the operon concept to explain how genes express themselves. They worked on the bacterium Escherichia coli.

• When lactose is added to the culture medium of E. coli, three enzymes are needed for the breakdown of lactose.
• Structural genes code for the synthesis of these enzymes. The functioning of these genes is regulated as a single unit by the operator gene. This entire unit is called an operon. A regulatory gene switches on or off the operator gene, which in turn regulates the activity of structural genes.

Jacob and Monod (1961) investigated the nature of induction of enzyme synthesis by E. coli. Of the 800 enzymes thought to be synthesized by E. coli, some are believed to be synthesized continuously and are called constitutive enzymes; others are synthesized only in the presence of an inducer compound, which may be the substrate, and are called inducible enzymes. β-galactosidase is an inducible enzyme.

NEET Biology Gene Expression And Regulation Notes

Read and Learn More NEET Biology Notes

Gene Regulation In Eukaryotes

• The regulation of gene expression in eukaryotes is more complex than in prokaryotes.
• In eukaryotes, the gene is split into exons and introns.
• Intron is also termed spacer DNA or IVS (Intervening sequence) The molecular basis of processes such as differentiation and development, cancer, and aging, all involve differential gene expression.
• Spliccosome Mediated Splicing

Spliceosonie. Spliceosomes are ellipsoid particles of RNA and protein; they arc -25 nm x 50 nm in size. They are assembled on the RNA precursors by an association of five different small nuclear ribonucleoproteins (snRNPs) and many proteins.

• Eukaryotic nuclei and cytoplasm contain many discrete small RNA species, called small nuclear RNAs, (snRNA) and small cytoplasmic RNAs (sc RNAs), respectively.
• The processing of the bulk of mRNA precursors is mediated by particles called spliceosomes. These mRNA precursors have many introns of variable lengths.
• Interestingly, the excision of introns does not seem to proceed sequentially, i.e., beginning at one end and progressing to the other, as is the case with transcription.
• Any intron of the mRNA precursor could be removed at a given point in time, but there seem to be some preferred patterns of their excision.

Genes

1. Housekeeping genes (Constitutive genes): The genes are constantly transcribed and expressed in the cells because the products they code for are constantly needed for cellular activities eg. genes for glycolysis, and ATP-ase to keep one alive.
2. Non Constitutive (Luxury Genes): These genes remain inactive and are expressed in certain cells only when the product they code for is needed. They are also called specialist genes e.g. gene for nitrate reductase in plants and lactose system in E. coli.
3. Viral oncogenes: A gene that can cause cell transformation in animal cells growing in culture and tumor formation in animals. They are twenty in number.
4. Proto-oncogene. A normal cellular gene that can be changed to an oncogene by mutation.
5. Nif (Nitrogen fixing) of plasmids: Plasmids are extrachromosomal DNA molecules present in addition to chromosomes in most bacteria. They can replicate like and independently of the chromosome. The plasmids carry genes for Resistance—R-genes and Nif (Nitrogen fixing).
6. Gram +ve gene: The gram +ve gene is present in gram +ve bacteria which take up the gram stain. They retain the blue color and are called Gram +ve bacteria.
7. Polygenes (Multiple genes/cumulative genes). There are many characteristics in both plants and animals that are controlled by cumulative action of dominant alleles of generally two or more independent genes e.g. height, weight, skin color in man, number of grains in an ear, and size of fruits.
8. The grani-ve gene is Present in Gram-ve bacteria which do not take up the blue colour of the Gram stain. The gram-ve bacteria can be observed with another stain such as safranin.
9. Inducible genes. Non-constitutive = Luxury gene, = Specialist gene.
10. Structural genes These genes code for chemical substances that contribute to morphological or functional traits of the cells.
    • These are nowadays called cistrons. These are of two types-Monocistronic and Polycistronic (code for many RNAs)
11. Polypeptide-coding genes These code for mRNA which in turn code for polypeptides.
12. Polyprotein-coding genes These code for more than one polypeptide per gene.
13. RNA coding genes Code for sRNA and tRNA. They are randomly repeated in the chromosomes.
14. Regulator genes Code for repressor proteins to regulate the transcription of cistrons.
15. The operator gene acts as a switch to turn on or off the transcription of a structural gene.
16. Promoter genes These genes are DNA sites where RNA polymerase binds for the transcription of RNA by the structural genes.
17. Terminator genes These genes are DNA regions where RNA polymerase activity stops to suspend the transcription of structural genes for example., UAA(Ochre), UAG (Amber), UGA (Opal)
18. Split genes Genes carrying information in pieces rather than in a continuous stretch are known as split genes such as introns /exons. The eukaryotic gene is split into exons and introns.
19. Introns. Eukaryote genes have inserts called introns which are transcribed but not translated between segments.
20. Exons are inserts of eukaryotic genes which are translated as well as transcribed.
21. F-gene (Fertility factor) contains genes for producing sex pilli and other characteristics needed for gene transfer.
22. Muton A segment of DNA that takes part in mutation
23. Subvital Genes Many mutant genes reduce the viability of the individuals carrying them in the appropriate genotype as compared to that of the normal individuals.
    • Such genes kill less than 90% of the individuals in which they are present in the appropriate genotype.
    • Most of the mutant genes are subviral in their effect, for example., miniature wings in Drosophila, some viridis mutants of barley, etc.
24. Vital Genes Those genes that do not affect the survival of the individuals in which they are present are known as vital genes.
    • Such genes neither enhance nor reduce the viability of the individuals carrying them. It does not imply that these genes are not necessary for the survival of the concerned organism.
    • It simply means that the survival of the organism is not affected by the fact that the concerned vital genes are present in the homozygous or heterozygous state. Wild-type alleles of all the genes of an organism are regarded as vital genes; they serve as the reference point in determining the effect of mutant alleles on survival.
25. Supervital Genes Some mutant alleles enhance the survival of those individuals that carry them in the appropriate genotype as compared to that of the wild-type allele, such genes are known as super ital genes.
    • Genes for disease resistance in a crop species may be regarded as superficial genes as they protect the individuals carrying them against the concerned disease and thus increase the chances of their survival in the presence of the concerned disease.
    • Similarly, genes conferring resistance/tolerance to the various abiotic stresses, for example., salinity, alkalinity, high temperature, low temperature, drought, etc., may also be regarded as superficial genes in that they enhance the fitness of the plants in the presence of the concerned stress.
26. Single Copy Gene They are present in a single copy (occasionally 2-3). They form 60-70% of the functional genes. Duplication mutation and exon reshuffling between two genes result formation of new genes
27. Repeated Genes These genes occur in multiple copies for example.,
    1. Histone genes
    2. Actin genes
    3. t-RNA and
    4. rRNA genes.
28. Multigenes (Multiple Gene Family). It is a group of similar or nearly similar genes for meeting the requirement of time and tissue-specific products e.g. globin gene family (ε,β,δ,γ) on chromosome 11, α, and β on chromosome 16.
29. Pseudogenes These are genes that have homology to functional genes but are unable to produce functional products due to intervening non-sense codons, insertions, deletions, and inactivation of promoter regions for example., several snRNA genes.
30. Processed genes Eukaryotic genes which lack introns, are formed probably due to reverse transcription or retroviruses. They are generally non-functional due to a lack of promoter genes.

NEET Biology Gene Expression And Regulation Notes

NEET Biology Gene Expression In Viruses

The term virus’ was coined by Dmitry Iwanovsky in 1892. Viruses are nucleoprotein structures devoid of cytoplasm, motility, irritability’ and energy generation they are intracellular obligate parasites using the metabolic machinery of their host for the multiplication and assembly of their parts.

• In a cell-free environment, a virus is inert and called a virion. It can be crystallized. Smallpox is the first viral disease studied by man.
• The first virus studied was the Tobacco Mosaic Virus (TMV). Mayer (1880) found that the sap of plants infected by Tobacco Mosaic could cause disease in healthy plants.
• Swarovski (1892) found that the infective property of sap remained intact even after passing through bacteria-proof filters.
• Viruses were first seen under a microscope by Takahashi and Rawlins (1933). TMV was crystallized by Stanley (1936).

Viral Reproduction Occurs By Following Ways

1. Lytic cycle in case of T₄ and other T even bacteriophages
2. Lysogenic cycle in case of λ (Lambda) phage.
3. Reproduction in single-stranded viruses such as Φ×l74 and coliphage fd. This single-stranded DNA is a plus strand and it forms a complementary negative strand, thus temporarily viruses become double-stranded.
   1. The double-stranded DNA or replicative DNA takes control over the machinery of the host and synthesizes strand DNA and protein for the assemblage of new viral particles.
4. Pinocytic Reproduction. The whole virus enters the host cells except the envelope. It is quite common in RNA viruses which are of two types :

RNA-RNA Viruses. DNA has no role in their multiplication.

After entering the host cell the viruses produce enzyme replicase which helps in producing more genetic RNA over the template of the present RNA genome. The latter also produces mRNAs for the synthesis of viral proteins.

RNA-DNA Viruses. They are also called retroviruses (Temin, 1970, e.g., Tumour/ Cancer Viruses, HIV) The viruses possess enzyme reverse transcriptase (Temin and Baltimore, 1972; in Rous Sarcoma Virus or RSV of Mouse).

• The enzyme builds DNA over the RNA genome. The phenomenon is called reverse transcription or feminism.
• The copied DNA (cDNA) builds its complementary strand. The double-strand copy DNA attaches to the host DNA/chromosome and is now called a provirus.
• It produces a chemical that disturbs cellular machinery. The cell with provirus may dedifferentiate and start dividing leading to cancer (uncontrolled growth forming tumor which sends branches/roots to invade different parts.)
• Some 20 viral oncogenes (genes that trigger cancer) have been recorded. However, no virus has been proven to cause cancer in humans.
• Humans have some protooncogenes (similar to viral oncogenes)which take part in growth but under certain circumstances, they get changed to cellular oncogenes.
• Jumping genes/transposons can also cause cancer. There are several chemicals, physical factors, and some viruses (e.g., Hepatitis B, Herpes, Papilloma, and Epstein-Barr Virus) that promote cancer.
• HIV (Human Immunodeficiency Virus) destroys the immune system of the body and causes AIDS. The provirus ultimately dissociates, transcribes viral RNA genomes, and produces reverse transcriptase and viral proteins.
• Different parts assemble to form retroviruses. The latter comes out through exocytosis or passes out to other cells through protoplasmic connections.

NEET Gene Expression And Regulation Chapter Notes

NEET Biology Gene Expression Gene Expression In Prokaryotes

In 1946, two American scientists, J. Lederbcrgand E.L.Tatum demonstrated sexuality in bacteria for the first time, and this opened a new era of research.

• The prokaryotic chromosome is circular. It is represented by a single double-stranded DNA molecule.
• It is usually attached to a cell membrane at one point and does not integrate with histones and is not bound by a membrane for example., bacteria and blue-green algae (cyanobacteria). Bacterial DNA is associated with few proteins. The genome of E.cali contains 2000 to 3000 genes.
• The bacterium can survive on a glucose diet giving the idea that its genes have information for the synthesis of practically all the organic compounds it needs.
• Mycoplasma (PPLO) has a genome of a few hundred genes that code for a few proteins. Bacteria divide very rapidly.
• The doubling time is also called generation time and it may be as low as 20 minutes. Bacteria mainly reproduce by asexual reproduction but do not exhibit true sexual reproduction as they do not produce a diploid phase. Thus, meiosis is lacking. However, bacteria exchange genetic material between two cells.

Modes Of Genetic Transfer In Bacteria

Three modes of genetic transfer between bacterial cells are:

1. Transformation
2. Transduction
3. Conjugation.

Transformation. It is also called the Griffith effect or the Recombination effect.

• The phenomenon by which DNA isolated from one type of cell, when introduced into another type can bestow some of its properties into the latter, is referred to as transformation.
• It was confirmed by Griffith with his experiments on the bacteria Streptococcus pneumoniae. Griffith used S-3 and R-2 strain out of S-1, S-2, S-3, and R-1, R-2 and R-3 strains

Transduction. The transfer of genetic material from one bacterium to another through bacteriophage is called transduction.

Transduction It Is Of Two Types:

1. Restricted and
2. Generalized transduction.

Conjugation:

Conjugation refers to the unidirectional transfer of DNA between cells via a cytoplasmic bridge. The process is analogous to sexual reproduction in eukaryotes.

• Occasionally, the F factor integrates into bacterial chromosomes. Such bacteria can transmit their genetic material into female cells with high frequency (Hfr) in a specific sequence.
• These are referred to as Hfr strains. Conjugation was initially established by Lcdcrberg and Tatum in Escherichia coli.
• The recombination frequency was exceedingly low in Lederberg’s studies. Hayes (1952) identified a strain of E. coli exhibiting a recombination frequency 100 to 1000 times greater than that reported by Lcdcrberg.
• The strain was designated as the high-frequency recombinant (Hfr) strain.

Conjugation It Is Of Two Types :

1. Sterile male method
2. A fertile male method that results in the formation of Hfr maniac or Supermale.

NEET Biology Gene Expression And Regulation Revision Notes

NEET Biology Gene Expression And Gene Regulation Important Contributors

Robert Briggs and Thomas Kings. Conducted experiments on nuclear transplantation and concluded that nuclei undergo some change during differentiation.

• Johanssen. Introduced and defined the term gene.
• Beadle And Tatum. Conducted experiments on Nenrospora and proposed one gene-one enzyme hypothesis. Yanofsky. Proposed one gene-one polypeptide hypothesis.
• Jacob And Monod. Found that genetic material possesses regulator gene units called operons. Shared Nobel Prize with Lwoff of France (1965).
• Pirk And Bowden. They found the nucleoprotein nature.
• Stanley. He was the first to isolate Tobacco Mosaic Virus (TMV) and crystallize the same. Lcdcrberg and Hayes discovered Plasmids.
• N.C. Jacole and Wolfman found the conversion of the plasmid into episome.
• Paul Berg— father of genetic engineering transferred gene SV 40 Virus into E.coli
• Safferman and Morris discovered cyanophages Barbera McClintock (Lady Mendel) discovered jumping genes. (The term transposon was given by Hedges and Jacob)

NEET Biology Gene Expression And Regulation Revision Notes

NEET Biology Gene Expression And Gene Regulation Gene Expression Synopsis

Prions (Prp) self self-duplicating protein molecules discovered first by Alper et al (1966) and cause diseases like scrapie and Kuru

• The term gene was given by Johanssen and genes are arranged in a linear order and the term Genetic code was given by Gamow.
• Cosmids are plasmids in which particular (passenger) DNA sequences have been inserted. They are novel vectors that combine the features of a plasmid and 1-phage. It carries genes for resistance to antibiotics. A cosmid has two sites of the RE enzyme
• Episomes are genetic elements of dual capacity to existing either as a chromosomal or as an extrachromosomal genetic element and are non-essential to the cell.
• Pseudogenes are DNA sequences derived from m-RNA through reverse transcription.
• Cancer-causing genes are called oncogenes (Discovered by Michael Bishop and Harold Varmin).

Nearly 20 viral genes have been identified which are involved in triggering cancerous cells.

• In 1988 Watson accepted the job as co-ordinator of “The Human Genome Project. ” Recent work in genetics is being done on this project.
• Carlson et. al. 1972 for the first time used the leaf protoplasts of Nicotiana glauca and N.langsdorjfii and successfully regenerated an interspecific hybrid plant.
• 2, 4-D promotes callus formation in cereals.
• Mitra and Kaul (1964) were among the first to produce risperidone from Rauwoljfia serpentina tissue culture. H.Kohn et. al. (1985) produced somatic hybrids in tobacco.
• Repetitive DNA. It consists of DNA nucleotides or base sequences which are few to several human base pairs (bp) long and are present in several to million copies per genome. Short sequences of bases are repeated hundreds of times in DNA.

Unique DNA. It consists of those DNA segments whose base sequences are present only in a single copy per genome i.e. their base sequences are not repeated in the genome.

• Promiscuous DNA. The DNA segments that have migrated from one organelle to another organelle i.e. chlo- roplast to mitochondria or vice versa.
• The discovery of promiscuous DNA has lent support to the endosymbiotic hypothesis of the origin of chloroplast and mitochondria.

Replication is of three types: viz

1. Conservative. A new strand is formed over the existing strand
2. Disruptive. Old strand undergoes fragmentation, the fragments synthesize complementary structures both of which assemble to form two replicas
3. Semiconservative. Because of the sequential opening of the DNA double chain and its replication to form two new chains DNA replication is called Zipper duplication.

Effect Of Medium Supplements On The Growth Of Mutants Of Neurospora Crassa:

NEET Biology Gene Expression And Regulation Study Material

Some Inhibitors Of Bacterial Protein Synthesis:

• RNA Polymerase 1. This enzyme is located in the nucleolus and is responsible for the transcription of ribosomal RNA. Polymerase I is not sensitive to a-ainanitin which is a bicyclic octapeptide.
• RNA Polymerase 2. This polymerase is located in the nucleoplasm which is part of the nucleus other than nucleolus. This enzyme is the major component of RNA polymerase activity, and it transcribes all the genes that produce mRNA.
• In eukaryotes, the transcript is initially in the form of mRNA precursors, called heterogeneous nuclear RNA (mRNA) which are later processed into mRNA (see, later). Polymerase I activity is rapidly inhibited by low concentrations of α-ainanitin.
• RNA Polymerase 3. It occurs in nucleoplasm and transcribe RNA and 5 RNA genes. It is inhibited by high levels of amanitin in animal cells but not in yeast and insects.

Inducer. A substance of low molecular weight that combines with a repressor and thus decreases the repression of protein synthesis. Repressor. A protein that switches on or off the operator gene is termed a repressor.

Gene Expression And Regulation NEET Chapter Summary

• Promoter. A part of an operon; is a nucleotide sequence to which RNA polymerase binds and initiates transcription. Also, a chemical substance that enhances the transformation of benign cells to cancerous cells.
• Regulator gene.  A gene that controls the rate of expression of another gene or genes. Example: The operon involved in lactose production of Escherichia coli has a regulator, an operator, and structural genes.
• Operator gene. A part of an operon that controls the activity of one or more structural genes.
• Operon. A group of genes makes up a regulatory or control unit. The unit includes an operator, a promoter, and structural genes.

Structural genes. A gene that controls actual protein production by determining the amino acid sequence (cf. Operator gene and Regulator gene.)

• Cistron. A gene segment that transcribes a single stretch of RNA is called a cistron or it is a unit of function in DNA
• Polycistronic. The long messenger RNA covering all the cistrons is called polycistronic.
• Introns. The regions of a gene which does not form part of mRNA and are removed during RNA processing before mRNA formation are referred to as introns.
• Exons. The region of a gene, which becomes part of mRNA and codes for different regions of the protein is referred to as exons.

Repressive enzyme.

Enzymes are synthesized in a cell in the absence of its final product. It is suppressed when the final product accumulates.

• The enzyme that can be activated. An enzyme is generated only in the presence of a substrate that functions as an inducer. Constitutive enzyme. An enzyme is synthesized in constant amounts irrespective of need (compared with inducible enzyme and repressive enzyme).
• Sexduction.The integration of bacterial genes via sex factors and their subsequent transmission through conjugation to a recipient cell.
• Sexual element. An episome (F+ in E. coli) allows a bacterial cell to serve as a donor of genetic material. The episome can be moved inside the cytoplasm during conjugation or integrated into the bacterial chromosome.
• Genetic equilibrium. State in a population of interbreeding organisms where specific gene frequencies remain unchanged across several generations.

Hfr. High-frequency recombination strain of Escherichia coli: the F episome is integrated into the bacterial chromosome.

• Lysis and Lytic bacteria. Bursting of a bacterial cell by the destruction of the cell membrane following infection by bacteriophage and such bacteria are called lytic bacteria.
• Lysogenic bacteria. Those harboring temperate bacterial phages.

NEET Biology Gene Expression Multiple Choice Questions

Question 1. Co-repressor is a:

1. Protein
2. Metabolite
3. Hormone
4. Enzyme.

Answer: 2. Metabolite

Question 2. Reverse transcription was discovered by :

1. Watson and Crick
2. Porter
3. Wilkins
4. Temin.

Answer: 4. Temin.

Question 3. In the operon concept, the regulator gene regulates chemical reactions in the cell by :

1. Inhibiting transcription of mRNA
2. Inactivating enzymes in the reaction
3. Inhibiting the substrate in the reactions
4. Inhibiting the migration of tn-RNA in cytoplasm.

Answer: 1. Inhibiting transcription of mRNA

Question 4. Which of the following statements is incorrect?

1. Genetic code is ambiguous.
2. Genetic code is degenerate.
3. Genetic code is universal.
4. Genetic code is non-overlapping.

Answer: 2. Genetic code is degenerate.

Read and Learn More NEET Biology Multiple Choice Question and Answers

MCQs on Regulation Of Gene Expression In Eukaryotes Question 5. In E. coli according to the operon concept, an operator gene combines with:

1. Inducer gene to switch on
2. Regulator protein to “switch on” structural gene transcription
3. Regulator gene to “switch off’ structural gene transcription
4. Regulator protein to switch off structural gene transcription.

Answer: 3. Regulator gene to “switch off’ structural gene transcription

Question 6. Exons and introns arc parts of :

1. DNA
2. RNA
3. mRNA
4. Circular DNA.

Answer: 1. DNA

Question 7. Eukaryotes have :

1. One promoter in gene structure
2. Two promoters in gene structure
3. No promoter gene
4. Many promoters in gene structure.

Answer: 3. No promoter gene

Question 8. In Rous sarcoma virus:

1. DNA → RNA→ Protein
2. RNA → DNA → Protein
3. RNA →DNA → RNA→ Protein
4. DNA → RNA → RNA → Proleins.

Answer: 4. DNA → RNA → RNA → Proleins

Question 9. Presence of F factor in bacteria :

1. Indicates it as male
2. Female
3. Fast factor
4. Free factor

Answer: 1. Indicates it as male

Question 10. The viral genes are expressed by :

1. Lytic processes
2. Lysogenic
3. Both 1 and 2
4. None of the above.

Answer: 3. Both 1 and 2

MCQs on Regulation Of Gene Expression In Eukaryotes Question 11. Which of the following is not a carcinogen?

1. X-rays
2. Virus
3. HNO₂
4. Starch.

Answer: 4. Starch

Question 12. According to the operon concept, the regulator gene forms.

1. An inducer
2. A repressor
3. A small peptide
4. A general inhibitor,

Answer: 2. A repressor

Question 13. Which virus has a double-stranded RNA?

1. Rheovirus
2. Φ×174
3. T₂ phage
4. TMV

Answer: 1. Rheovirus

Question 14. In the lysogenic cycle, the virus is:

1. Virulent
2. Temperate
3. Harmless to the host cell
4. Reproduces slowly.

Answer: 2. Temperate

Question 15. In bacteria, the exchange of genetic material between two different cells is brought by the process of:

1. Transformation
2. Transduction
3. Conjugation
4. All of the above

Answer: 4. All of the above

Question 16. Phage host represents :

1. Virion protein coat
2. Virion nucleic acid
3. Virion protein and nucleic acid
4. None of the above.

Answer: 1. Virion protein coat

MCQs on Regulation Of Gene Expression In Eukaryotes Question 17. The regulated unit of genetic material is called :

1. Operator gene
2. Regulator
3. Operon
4. Promoter gene.

Answer: 3. Operon

Question 18. A retrovirus is:

1. TMV
2. HIV
3. Papillomavirus
4. Both 2 and 3

Answer: 2. HIV

Question 19. Bacteriophages are :

1. Modified bacteria
2. Primitive bacteria
3. Viruses infecting bacteria
4. Viruses infecting cyanobacteria.

Answer: 3. Viruses infecting bacteria

Question 20. Provirus differs from prophage about:

1. Integration of RNA with host DNA
2. Integration of genetic DNA with host DNA
3. Integration of copy DNA of retrovirus with host DNA
4. None of above

Answer: 3. Integration of copy DNA of retrovirus with host DNA

Question 21. Which virus has a rod-shaped structure 7

1. Rlieo viruses
2. Φ×174
3. T phage
4. TMV.

Answer: 4. TMV

Question 22. Tryptophan Operon is:

1. Repressible system
2. Inducible
3. Controlled by regulator gene
4. Made of 3 structural genes.

Answer: 1. Repressible system

MCQs on Regulation Of Gene Expression In Eukaryotes Question 23. The presence of F-Factor in bacteria helps as :

1. Fertility factor
2. Female
3. Fast factor
4. Free factor.

Answer: 1. Fertility factor

Question 24. Exons and Introns are parts of;

1. DNA
2. mRNA
3. RNA
4. None of the above

Answer: 1. DNA

Gene Regulation Recommended MCQs  Question 25. Eukaryotes have:

1. One glue per cell
2. Ten genes per cell
3. Hundred genes per cell
4. Thousand genes per cell.

Answer: 4. Thousand genes per cell.

Question 26. Oncogenic viruses are harmful in :

1. Provirus stage
2. Lytic phase
3. Prophage stage
4. Hybrid stage,

Answer: 1. Provirus stage

Question 27. Which of the following viruses have been extensively used to fuse cells in tissue culture :

1. Sendai virus
2. T₂ viruses
3. Phage lambda
4. TMV,

Answer: 1. Sendai virus

Question 28. Jumping genes in maize were discovered by :

1. H.G. Khorana
2. Beadle
3. Barbara McClintock
4. Jacob.

Answer: 3. Barbara McClintock

Gene Regulation Recommended MCQs  Question 29. Thalassemia is an example of:

1. Mutation
2. Silent mutation
3. Frameshift mutation
4. Genetic disorders.

Answer: 3. Frameshift mutation

Question 30. Who found the occurrence of sexuality in bacteria ‘!

1. Lederberg and Tatum
2. Beadle and Tatum
3. Sutton and Boveri
4. Briggs and Kings.

Answer: 1. Lederberg and Tatum

Question 31. Operon consists of the following :

1. Regulator and repressor
2. Regulator, structural, and operator
3. Regulator, structural, operator, and promoter
4. Regulator and operator.

Answer: 3. Regulator, structural, operator, and promoter

Question 32. Restriction enzymes are used in genetic engineering because :

1. They can cut DNA at specific base sequences.
2. They are proteolytic enzymes which can degrade harmful proteins.
3. They are nucleases that cut DNA at various sites
4. They can join different DNA fragments.

Answer: 1. They can cut DNA at specific base sequence

Question 33. Wild-type E.cali cells are growing in a normal medium with glucose. They are transferred to a medium containing only lactose as the sugar. Which one of the following changes takes place?

1. The lac operon is repressed
2. All operons are induced
3. E.coli cells stop dividing
4. The lac operon is induced.

Answer: 4. The lac operon is induced

Gene Regulation Recommended MCQs  Question 34. An environmental agent that triggers transcription from an operon is a :

1. Derepressor
2. Inducer.
3. Regulator
4. Controlling element.

Answer: 2. Inducer

Question 35. The lac operon is an example of:

1. Arabinose operon
2. Inducible operon
3. Repressive operon
4. Overlapping genes,

Answer: 2. Inducible operon

Question 36. In split genes, the coding sequences are called :

1. Cistrons
2. Operons
3. Exons
4. Introns.

Answer: 3. Exons

Question 37. In the case of cyanobacteria :

1. DNA → RNA → Protein
2. RNA → DNA → Protein
3. RNA → DNA → RNA → Protcin
4. DNA → RNAH → RNA → Proteins.

Answer: 1. DNA → RNA → Protein

Question 38. A retrovirus is :

1. TMV
2. HIV
3. Rheo virus
4. Both 2 and 3

Answer: 4. Both 2 and 3

Question 39. The sequence of structural genes of Lac operon is :

1. Lac Z, Lac Y, Lac A
2. Lac Y, Lac Z, Lac A
3. Lac A, Lac Z, Lac Y
4. Lac A, Lac Y, Lac Z.

Answer: 1. Lac Z, Lac Y, Lac A

Gene Regulation Recommended MCQs  Question 40. Which virus has a single-stranded DNA :

1. Rhevirus
2. Φ×174 virus
3. T2 phage
4. TMV.

Answer: 2. Φ×174 virus

Question 41. In the lytic cycle, the virus is :

1. Virulent
2. Temperate
3. Harmless to the host cell
4. Reproduces slowly.

Answer: 1. Virulent

Question 42. Resistance to antibiotics is a genetic trait that spreads naturally from one type of bacterium to :

1. Another bacterium of the same strain
2. Enkaryolic cells of all types
3. Almost any other type of bacterium
4. Any other cell containing copy DNA.

Answer: 3. Almost any other type of bacterium

Gene Regulation in Eukaryotes NEET Questions Question 43. Reverse transcriptase is :

1. RNA-dependent DNA polymerase
2. RNA-dependent RNA polymerase
3. DNA-dependent RNA polymerase
4. DNA-dependent DNA polymerase

Answer: 2. RNA-dependent RNA polymerase

Question 44. Transduction in bacteria is mediated by :

1. Cosmids
2. Phage vectors
3. Plasmid vectors
4. F-factors.

Answer: 2. Phage vectors

Question 45. The nuclease enzyme which begins its attack from a free end of a polynucleotide :

1. Endonuclease
2. Kinase
3. Exonuclease
4. Polymerase.

Answer: 3. Exonuclease

Question 46. Normally, the DNA molecule has A-T, and G-C pairing. However, these bases can exist in alternative, valency consistent status, owing to rearrangement called :

1. Tautomerization
2. Base analogue
3. Frameshift mutation
4. Point mutation

Answer: 3. Frameshift mutation

Question 47. The fertility factor or F⁺ factor that plays a key role in conjugation is a:

1. Retrovirus
2. Plasmid
3. Viroid
4. Lysogenic phage

Answer: 2. Plasmid

Question 48. When DNA is exchanged between two bacteria via cytoplasmic bridges, the process is called :

1. Transformation
2. General transduction
3. Restricted transduction
4. Conjugation.

Answer: 4. Conjugation

Gene Regulation in Eukaryotes NEET Questions Question 49. When a bacteriophage, in its lytic phage, carries some of the bacterium’s partially digested chromosome with it to another host cell, the process is called :

1. Transformation
2. General transduction
3. Restricted transduction
4. Conjugation

Answer: 2. General transduction

Question 50. In general, bacterial genes are regulated at the time of:

1. Transcription
2. Translation
3. Post translation
4. Post transcription.

Answer: 1. Transcription

Question 51. The activity of a repressor depends on whether :

1. The repressor is positioned next to the operon
2. The repressor is positioned next to the promoter
3. A key substance in the metabolic pathway is present
4. There is enough RNA polymerase present.

Answer: 2. The repressor is positioned next to the promoter

Question 52. In gene therapy, DNA is inserted in a cell to compensate for :

1. The absence of plasmid
2. Mutant alleles
3. Holes in the DNA made by viruses
4. The lack of copy DNA.

Answer: 2. Mutant alleles

Question 53. In the lac operon structural gene ‘Z’ is responsible for the synthesis of the enzyme :

1. β-galactosidase
2. Galactosidase permease
3. Galactosidase transacetylase.

Answer: 1. β-galactosidase

Gene Regulation in Eukaryotes NEET Questions Question 54. In the genetic code dictionary, how many codons are used to code for all the 20 amino acids?

1. 64
2. 61
3. 60
4. 20.

Answer: 2. 61

Question 55. Replication of DNA occurs during the S-phase of interphase Okazaki fragments are joined in a correct sequence by:

1. DNA polymerase I
2. DNA ligase
3. Primase and helicase
4. RNA polymerase.

Answer: 2. DNA ligase

Question 56. Which of the following makes use of RNA as a template to synthesize DNA?

1. DNA polymerase
2. RNA polymerase
3. Reverse transcriptase
4. DNA-dependent RNA polymerase.

Answer: 3. Reverse transcriptase

Question 57. Which one of the following triplet codes is correctly matched with its specificity for an amino acid in protein synthesis or as a start or stop signal?

1. UUU – Stop
2. UGU Lencino
3. UAC – Tyrosine
4. UCG – Start.

Answer: 2. UGU Lencino

Question 58. How many genes are present on chromosomes Y and A respectively :

1. 2869,231
2. 232, 2968
3. 231,2968
4. 2968,231.

Answer: 3. 231,2968

Gene Regulation in Eukaryotes NEET Questions Question 59. UTR is present on :

1. MRNA at one end
2. 3′ end of tRNA
3. 5′ and 3′ end of mRNP
4. 3′ end 5′ end of tRNA.

Answer: 3. 5′ and 3′ end of mRNP

Regulation of Gene Expression in Eukaryotes MCQ Question 60. Which of the following is a ‘dual function’?

1. AUG
2. UUU
3. GUA
4. CCC.

Answer: 1. AUG

Question 61. The base sequence for a nucleic acid segment is given as GAG AGG GGA CCA. From this it can be concluded that it is a segment of:

1. DNA strand
2. mRNA
3. t-RNA strand
4. Data is not sufficient.

Answer: 4. Data not sufficient

Question 62. Which of the following does not follow the central dogma of molecular biology?

1. mUcor
2. Chlamydomonas
3. HIV
4. Mycobacterium.

Answer: 3. HIV

Question 63. The largest gene in humans is

1. Oncogene
2. Tumor suppress gene
3. Dystrophin
4. Insulin.

Answer: 3. Dystrophin

Question 64. In a DNA molecule, adenine is 15% what would be % the age of Guanine?

1. 15%
2. 30%
3. 35%
4. 85%.

Answer: 3. 35%

Regulation of Gene Expression in Eukaryotes MCQ Question 65. The length of DNA with 23 base pairs is :

1. 78.4 A°
2. 78.2
3. 78 A°
4. 74.8A°

Answer: 2. 78.2

Question 66. Which of the following have ds RNA?

1. TMV
2. Ribozyme
3. SnRNA
4. Rheovirus.

Answer: 4. Rheovirus

Question 67. Regulation of lac operon by repressor is referred to as :

1. +ve regulation
2. – ve regular
3. Repressible
4. Anabolic.

Answer: 2. – ve regular

Question 68. The accessibility of the promoter region of prokaryotic DNA is many cases regulated by the interaction of proteins with a sequence termed operator. The operator region is adjacent to :

1. Structural gene
2. Regulator gene
3. Promoter element
4. Gene ‘a’.

Answer: 3. Promoter element

Question 69. At the time of organogenesis, genes regulate the process at different levels and a different times due to the:

1. Promoter
2. Regulator
3. Intron
4. Exon.

Answer: 4. Exon

Question 70. In Negative operon :

1. Co-repressor binds with repressor
2. Co-repressor does not bind with the repressor
3. Corepressor binds with inducer.
4. cAMP hurts lac operon

Answer: 1. Co-repressor binds with repressor

Regulation of Gene Expression in Eukaryotes MCQ Question 71. Restriction enzymes:

1. Are endonucleases that cleave DNA at specific sites
2. Make DNA complementary to an existing DNA or RNA
3. Cut or join DNA fragments
4. Are required in vectorless direct gene transfer.

Answer: 1. Are endonucleases which cleave DNA at specific sites

Question 72. The process of introduction of foreign genes for improving genotype is called :

1. Tissue culture
2. Vernalization
3. Genetic engineering
4. Eugenics.

Answer: 4. Eugenics

Question 73. The diagram shows an important concept in the genetic implication of DNA. Fill in the blanks A to C.

1. A – translation B – transcription C – Erevin Chargaff
2. A – transcription B – translation C – Francis Crick
3. A – translation B – extension C – Rosalind Franklin
4. A – transcription B – replication C – James Watson

Answer: 2. A – transcription B – translation C – Francis Crick

Question 74. Which one of the following conditions though harmful in itself, is also a potential saviour from all mosquito-borne infectious diseases?

1. Pernicious anemia
2. Leukaemia
3. Thalassaemia
4. Sickle cell anemia.

Answer: 4. Sickle cell anemia

Question 75. In E. coli, during lactose metabolism repressor binds to :

1. Regulator gene
2. Promoter gene
3. Operator gene
4. Structural gene.

Answer: 2. Promoter gene

MCQs on Regulation Of Gene Expression In Eukaryotes Question 76. The genes are responsible for the growth and differentiation of living organisms through the regulation of :

1. Translation
2. Transcription
3. Transduction
4. Both 1 and 2

Answer: 3. Transduction

Question 77. Which of the following is specifically used in genetic engineering?

1. Ligase
2. Gyrase
3. Restriction endonuclease
4. DNA polymerase.

Answer: 3. Restriction endonuclease

Question 78. Restriction endonucleases :

1. Are present in mammalian cells for degradation of DNA when the cell dies
2. Are used in genetic engineering for ligating two DNA molecules
3. Are used for in vitro DNA synthesis
4. Are synthesized by bacteria as part of their defense

Answer: 4. Are synthesized by bacteria as part of their defense

Question 79. Cancer cells are more easily damaged by radiation than normal cells because they are :

1. Starved of mutation
2. Undergoing rapid division
3. Different in structure
4. Non-dividing.

Answer: 2. Undergoing rapid division

Question 80. DNA fingerprinting refers to :

1. Molecular analysis of profiles of DNA samples
2. Analysis of DNA sample using imprinting device
3. Techniques used for molecular analysis of different specimens of DNA
4. Techniques used for identification of fingerprints of

Answer: 4. Techniques used for the identification of fingerprints of

Question 81. What kind of evidence suggested that man is more closely related to chimpanzees than to other hominoid apes?

1. Evidence from DNA from sex chromosomes only
2. Comparison of chromosomal morphology only
3. Evidence from fossil remains and the fossil mitochondrial DNA alone
4. Evidence from DNA extracted from sex chromosomes, autosomes, and mitochondria.

Answer: 4. Evidence from DNA extracted from sex chromosomes, autosomes, and mitochondria

Question 82. In transgenics, expression of transgene in target tissue is determined by :

1. Enhancer
2. Promoter
3. Transgene
4. Reporter.

Answer: 4. Reporter

MCQs on Regulation Of Gene Expression In Eukaryotes Question 83. The Ti plasmid is often used for making transgenic plants. This plasmid is found in :

1. Azotobacter
2. Rhizobium of the roots of leguminous plants
3. Agrobacterium
4. yeast as a 2μm plasmid.

Answer: 3. Agrobacterium

Question 84. Which enzyme/s will be produced in a cell in which there is a nonsense mutation in the lac Y gene?

1. Lactose permease
2. Transacetylase
3. Lactose permease and transacetylase
4. β-galactosidase.

Answer: 4. β-galactosidase.

Question 85. Supercoiled DNA can be traced in :

1. Prokaryotes and eukaryotes
2. Eukaryotes only
3. Prokaryotes only
4. None of these

Answer: 1. Prokaryotes and eukaryotes

Question 86. Phosphorus is present in :

1. Protein
2. DNA
3. RNA
4. Both DNA and RNA.

Answer: 4. Both DNA and RNA

Question 87. In a given DNA segment ATG, ACC, AGG, ACC, CCA, ACA, the first base gets mutated. The effect of this on coding by this DNA segment will result in :

1. A complete change in the type as well as a sequence of amino acids
2. Change in the first amino acid only
3. One amino acid less in the protein
4. No change in the sequence
5. No coding.

Answer: 2. One amino acid less in the protein

MCQs on Regulation Of Gene Expression In Eukaryotes Question 88. Okazaki fragments are joined in a correct sequence by :

1. DNA polymerase I
2. DNA ligase
3. RNA polymerase
4. Primase
5. Heliease.

Answer: 2. DNA ligase

Question 89. In the lac operon, the structural genes are switched off when :

1. The repressor binds to the operator
2. Repressor binds to the promoter
3. The repressor binds to the regulator
4. Repressor binds to the inducer
5. The repressor binds to the allolactose.

Answer: 1. The repressor binds to the operator

Question 90. In the lac operon structural gene V is responsible for the synthesis of the enzyme :

1. β-galactosidase
2. Galactosidase permease
3. Galactosidase transacetylase
4. None of these.

Answer: 1. β-galactosidase

Question 91. When lactose is added to the culture of E.coli, a few of its molecules get into the cells with the help of:

1. Galactosidase
2. Permease
3. Lactase
4. Transacetylase.

Answer: 2. Permease

Gene Regulation Recommended MCQs Question 92. During transcription, holoenzyme RNA polymerase binds to a DNA sequence and the DNA assumes a saddle Ike structure at that point. What is that sequence called?

1. TATA box
2. AAAT box
3. GGTT box
4. CAAT box

Answer: 1. TATA box

Question 93. In the lac operon model, lactose molecules function a is :

1. Inducers that bind with the operator gene
2. Repressors that bind with the operator gene
3. Inducers that bind with the repressor protein
4. Compressors that bind with repressor protein.

Answer: 3. Inducers that bind with the repressor protein

Question 94. Protein synthesis in an animal cell occurs :

1. Only on the ribosomes present in the cytosol
2. Only on ribosomes attached to the nuclear envelope and endoplasmic reticulum
3. On ribosomes present in the nucleolus as well as in the cytoplasm
4. No ribosomes are present in the cytoplasm as well as in mitochondria.

Answer: 4. No ribosomes present in the cytoplasm as well as in mitochondria

Question 95. E.coli cells with a mutated z gene of the lac operon cannot grow in a medium containing only lactose as the source of energy because :

1. In the presence of glucose, E.coli cells do not utilize lactose
2. They cannot transport lactose from the medium into the cell
3. The lac operon is constitutively active in these cells
4. They cannot synthesize functional beta-galactosidase.

Answer: 4. They cannot synthesize functional beta-galactosidase

Question 96. Which one of the following makes use of RNA as a template to synthesize DNA?

1. Reverse transcriptase
2. DNA dependant RNA polymerase
3. DNA polymerase
4. RNA polymerase.

Answer: 1. Reverse transcriptase

Question 97. Differentiation of organs and tissues in a developing organism is associated with:

1. Differential expression of genes
2. Lethal mutations
3. Deletion of genes
4. Developmental mutations.

Answer: 1. Differential expression of genes

Gene Regulation Recommended MCQs Question 98. Intron transcripts in heterogenous nuclear RNA (hn- RNA) are removed and exon transcripts are joined together under the direction of protein complexes. These complexes are :

1. Polysomes
2. Cdk complex
3. Spliceosomes
4. Endopeptidases.

Answer: 3. Spliceosomes

Question 99. In regulation of gene expression in prokaryotes :

1. Lactose acts as the suppressor for gene expression
2. Tryptophan acts as the inducer of gene expression
   
3. The regulator gene is the one that produces the repressor molecule

1. 1 alone correct
2. alone correct
3. 3 alone correct
4. 2 and 3 are correct.

Answer: 3. 3 alone correct

Question 100. The sequence of structural genes in the lac operon concept is :

1. Lac A, lac Z, lac Y
2. Lac A, lac Y, lac Z
3. Lac Y, lac Z, lac A
4. Lac Z, lac Y, lac A.

Answer: 4. Lac Z, lac Y, lac A.

Gene Regulation in Eukaryotes NEET Questions Question 101. All genes located on the same chromosome :

1. Form different groups depending on their relative distance
2. Form one linkage group
3. Will not form any linkage groups.
4. Form interactive groups that affect the phenotype

Answer: 2. Will not form any linkage groups.

Question 102. Conditions of a karyotype 2 n+1 and 2n ± 2 are called:

1. Aneuploidy
2. Polyploidy
3. Allopolyploidy
4. Monosomy.

Answer: 1. Aneuploidy

Question 103. Distance between the genes and advantage of recombination shows :

1. A direct relationship
2. An inverse relationship
3. A parallel relationship
4. No relationship.

Answer: 2. An inverse relationship

Question 104. If genetic disease is transferred from a phenotypically normal but carrier female to only some of the male progeny, the disease is :

1. Autosomal dominant
2. Autosomal recessive
3. Sex-linked dominant
4. Sex-linked recessive.

Answer: 4. Sex-linked recessive.

Question 105. In sickle cell anaemia glutamic acid is replaced by valine. Which one of the following triplets codes for valine?

1. G G G
2. A A G
3. GAA
4. GUG.

Answer: 4. GUG.

Question 106. A person having genotype IA IB would show the blood group as AB. This is because of:

1. Pleiotropy
2. Co-dominance
3. Segregation
4. Incomplete dominance.

Answer: 2. Co-dominance

Gene Regulation in Eukaryotes NEET Questions Question 107. ZZ / ZW type of sex determination is seen in :

1. Platypus
2. Snails
3. Cockroach
4. Peacock.

Answer: 4. Peacock.

Question 108. A cross between two tall plants resulted in offspring having few dwarf plants. What would be the genotypes of both the parents?

1. TT and Tt
2. Tt and Tt
3. TT and TT
4. Tt and tt.

Answer: 2. Tt and Tt

Question 109. In a dihybrid cross, if you get a 9:3:3:1 ratio it denotes that:

1. The alleles of two genes interact with each other
2. It is a multigenic inheritance
3. It is a case of multiple alleles
4. The alleles of two genes segregate independently.

Answer: 4. The alleles of two genes are segregating independently.

Question 110. Which of the following will not result in variations among siblings?

1. Independent assessment of genes
2. Crossing over
3. Linkage
4. Mutation.

Answer: 3. Linkage

Question 111. Mendel’s law of independent assortment holds good for genes situated on the :

1. Non-homologous chromosomes
2. Homologous chromosomes
3. Extranuclear genetic element
4. Same chromosome.

Answer: 1. Non-homologous chromosomes

Gene Regulation in Eukaryotes NEET Questions Question 112. Occasionally, a single gene may express more than one effect. The phenomenon is called :

1. Multiple allelism
2. Mosaicism
3. Pleiotropy
4. Polygeny.

Answer: 3. Pleiotropy

Question 113. In a certain taxon of insects, some have 1 7 chromosomes and the others have 18 chromosomes. The 17 and 18 chromosome-bearing organisms are :

1. Males and females, respectively
2. Females and males, respectively
3. All males
4. All females.

Answer: 1. Males and females, respectively

Question 114. The inheritance pattern of a gene over generations among humans is studied by the pedigree analysis. The character studied in the pedigree analysis is equivalent to :

1. Quantitative trait
2. Mendelian trait
3. Polygenic trait
4. Maternal trait.

Answer: 2. Mendelian trait

Question 115. It is said that Mendel proposed that the factor controlling any character is discrete and independent. This proposition was based on the :

1. Results of F₃ generation of a cross.
2. Observations that the offspring of a cross made between the plants having two contrasting characters show only one character without any blending.
3. Self-pollination of F₁ offspring
4. Cross-pollination of parental generations.

Answer: 2. Observations that the offspring of a cross made between the plants having two contrasting characters show only one character without any blending.

Question 116. Two genes ‘A’ and ‘B’ are linked. In a dihybrid cross involving these two genes, the F₁ heterozygote is crossed with the homozygous recessive parental type (aa bb). What would be the ratio of offspring in the next generation?

1. 1 : 1: 1: 1
2. 9 : 3 : 3: 1
3. 3:1
4. 1: 1.

Answer: 1. 1: 1 : 1: 1

Question 117. In the F₂ generation of a Mendelian dihybrid cross the number of phenotypes and genotypes are :

1. Phenotypes – 4; genotypes – 16
2. Phenotypes – 9; genotypes – 4
3. Phenotypes – 4; genotypes – 8
4. Phenotypes – 4; genotypes – 9

Answer: 4. Phenotypes – 4; genotypes – 9

Regulation of Gene Expression in Eukaryotes MCQ Question 118. The mother and father of a person with the ‘O’ blood group have ‘A’ and ‘B’ blood groups respectively. What would be the genotype of both mother and father?

1. The mother is homozygous for the ‘A’ blood group and the father is heterozygous for ‘B’.
2. Mother is heterozygous for ‘A’ blood group and father is homozygous for ‘B’
3. Both mother and father are heterozygous for the ‘A’ and ‘B’ blood groups, respectively
4. Both mother and father are homozygous for the ‘A’ and ‘B’ blood groups, respectively.

Answer: 3. Both mother and father are heterozygous for the ‘A’ and ‘B’ blood groups, respectively

Question 119. In a DNA strand, the nucleotides are linked together by:

1. Glycosidic bonds
2. Phosphodiester bonds
3. Peptide bonds
4. Hydrogen bonds.

Answer: 2. Phosphodiester bonds

Question 120. A nucleoside differs from a nucleotide. It lacks the

1. Base
2. Sugar
3. Phosphate group
4. Hydroxyl group.

Answer: 3. Phosphate group

Question 121. Both deoxyribose and ribose belong to a class of sugars called :

1. Trioses
2. Hexoses
3. Pentoses
4. Polysaccharides.

Answer: 3. Pentoses

Question 122. The fact that a purine base is always paired through hydrogen bonds with a pyrimidine base leads to, in the DNA double helix :

1. The antiparallel nature
2. The semi-conservative nature
3. Uniform width throughout DNA
4. Uniform length in all DNA.

Answer: 3. Uniform width throughout DNA

Question 123. The net electric charge on DNA and histones is :

1. Both positive
2. Both negative
3. Negative and positive, respectively
4. Zero

Answer: 3. Negative and positive, respectively

Regulation of Gene Expression in Eukaryotes MCQ Question 124. The promoter site and the terminator site for transcription are located at :

1. 3’ (downstream) end and 5’ (upstream) end, respectively of the transcription unit
2. 5’ (upstream) end and 3’ (downstream) end, respectively of the transcription unit
3. The 5’ (upstream) end
4. The 3’ (downstream) end.

Answer: 2. 5’ (upstream) end and 3’ (downstream) end, respectively of the transcription unit

Question 125. Which of the following statements is the most appropriate for sickle cell anemia?

1. It cannot be treated with iron supplements
2. It is a molecular disease
3. It confers resistance to acquiring malaria
4. All of the above.

Answer: 4. All of the above

Question 126. One of the following is true concerning AUG

1. It codes for methionine only
2. It is also an initiation codon
3. It codes for methionine in both prokaryotes and eukaryotes
4. All of the above.

Answer: 4. All of the above

Question 127. The first genetic material could be :

1. Protein
2. Carbohydrates
3. DNA
4. RNA

Answer: 4. RNA

Question 128. About mature ntRNA in eukaryotes :

1. Exons and introns do not appear in the mature RNA
2. Exons appear but introns do not! appear in the mature RNA
3. Introns appear but exons do not appear in the mature RNA
4. Both exons and introns appear in the mature RNA.

Answer: 2. Exons appear but introns do not! appear in the mature RNA

Question 129. The human chromosomes with the highest and least number of genes in them are respectively :

1. Chromosome 21 and Y
2. Chromosome 1 and X
3. Chromosome 1 and Y
4. Chromosome X and Y.

Answer: 3. Chromosome 1 and Y

Question 130. Who amongst the following scientists had no contribution in the development of the double helix model for the structure of DNA?

1. Rosalind Franklin
2. Maurice Wilkins
3. Erwin Chargaff
4. Meselson and Stahl.

Answer: 4. Meselson and Stahl.

Question 131. DNA is a polymer of nucleotides that are linked to each other by a 3″-5’ phosphodiester bond. To prevent the polymerization of nucleotides, which of the following modifications would you choose?

1. Replace purine with pyrimidines
2. Remove/Replace 3″ OH group in deoxyribose
3. Remove/Replacc 2’ OH group with some other group in deoxyribose
4. Both ‘2’ and ‘3’.

Answer: 2. Remove/Replace 3″ OH group in deoxyribose

Question 132. Discontinuous synthesis of DNA occurs in one strand, because :

1. DNA molecule being synthesized is very long
2. DNA-dependent DNA polymerase catalyzes polymerization only in one direction (5’- 3’)
3. It is a more efficient process
4. DNA ligase has to have a role.

Answer: 2. DNA-dependent DNA polymerase catalyzes polymerization only in one direction (5’-3’)

Regulation of Gene Expression in Eukaryotes MCQ Question 133. Which of the following steps in transcription is catalyzed by RNA polymerase?

1. Initiation
2. Elongation
3. Termination
4. All of the above.

Answer: 2. Elongation

Question 134. Control of gene expression takes place at the level of:

1. DNA-replication
2. Transcription
3. Transition
4. None of the above

Answer: 2. Transcription

Question 135. Regulatory proteins are the accessory proteins that interact with RNA polymerase and affect its role in transcription. Which of the following statements is correct about regulatory protein?

1. They only increase expression
2. They only decrease expression.
3. They interact with RNA polymerase but do not affect the expression
4. They can act both as activators and as repressors

Answer: 4. They can act both as activators and as repressors

Question 136. Which was the last human chromosome to be completely sequenced :

1. Chromosome 1
2. Chromosome 11
3. Chromosome 21
4. Chromosome X.

Answer: 1. Chromosome 1

Question 137. Which of the following are the functions of RNA?

1. It is a carrier of genetic information from DNA to ribosomes synthesizing polypeptides
2. It carries amino acids to ribosomes
3. It is a constituent component of ribosomes
4. All of the above.

Answer: 4. All of the above.

Question 138. While analyzing tire DNA of an organism a total number of 5386 nucleotides were found out of which the proportion of different bases was: Adenine = 29%, Guanine = 17%, Cytosine = 32%. Thymine = 17%. Considering Chargaffs rule it can be concluded that:

1. It is a double-stranded circular DNA
2. It is a single-stranded DNA
3. It is a double-stranded linear DNA
4. No conclusion can be drawn.

Answer: 2. It is single-stranded DNA

Question 139. In some viruses, DNA is synthesized by using RNA as a template. Such a DNA is called :

1. A-DNA
2. B-DNA
3. cDNA
4. DNA.

Answer: 3. cDNA

Question 140. IfMeselson and Stahl’s experiment is continued for four generations in bacteria, the ratio of 15_N-/15_N: 15_N/14_N/: 1 4_N/ 14_N containing DNA in the fourth generation would be :

1. 1:1:0
2. 1:4:0
3. 0:l:3
4. 0:1:7.

Answer: 4. 0:1:7

Question 141. If the sequence of nitrogen bases of the coding strand of DNA in a transcription unit is: 5’ – ATG A ATG-3’, the sequence of bases in its RNA transcript would be :

1. 5’ – AUG A AUG-3’
2. 5’-UACUUAC-3’
3. 5’ – CAUUCAU-3’
4. 5’ – G U A A G U A – 3’.

Answer: 1. 5’ – AUG A AUG-3’

Question 142. The RNA polymerase holoenzyme transcribes :

1. The promoter, structural gene, and the terminator region
2. The promoter, and the terminator
3. The structural gene and the terminator regions
4. The structural gene only.

Answer: 3. the structural gene and the terminator regions

Question 143. If the base sequence of a codon mmRNA is 5’-AUC- 3’, the sequence of tRNA pairing with it must be :

1. 5’ – UAC – 3’
2. 5’ – CAU – 3’
3. 5’ -AUG -3’
4. 5’ – GUA – 3’

Answer: 2. 5’ – CAU – 3’

Question 144. The amino acid attaches to the tRNA at its :

1. 5’-end
2. 3’-end
3. Anti codon site
4. DHU loop

Answer: 2. 3’-end

Question 145. To initiate translation, the mRNA first binds to :

1. The smaller ribosomal sub-unit,
2. The larger ribosomal sub-unit
3. The whole ribosome
4. No such specificity exists.

Answer: 1. The smaller ribosomal sub-unit,

Question 146. In E.coli, the lac operon gets switched on when :

1. lactose is present and it binds to the repressor
2. The repressor binds to the operator
3. RNA polymerase binds to the operator
4. Lactose is present and it binds to RNA polymerase.

Answer: 1. lactose is present and it binds to the repressor

Question 147. Which of the following statements are correct?

1. RNA polymerase 1 transcribes rRNAs
2. RNA polymerase 2 transcribes snRNAs
3. RNA polymerase 3 transcribes hnRNA
4. RNA polymerase 2 transcribes hnRNA.

1. 1 and 2 correct
2. 1 and 3 are correct
3. 1, 2, and 4 are correct
4. 2 and 3 are correct
5. 1 and 4 are correct.

Answer: 5. 1 and 4 are correct.

Question 148. In Hershey and Chase experiments, radioactive ³²P was used to culture bacteriophages which resulted in radioactive :

1. ViralDNA
2. Bacterial capsule
3. Viral proteins
4. Plasma membrane of bacteria.

Answer: 1. ViralDNA

Question 149. The inducer for switching ‘on’ the lac operon in bacteria is:

1. Presence of lactose
2. Number of bacteria
3. Presence of structural genes in the bacteria
4. Presence of sucrose
5. Presence of RNA polymerase

Answer: 1. Presence of lactose

Question 150. Select the incorrect statement (s):

1. Six codons do not code for any amino acid.

2. Codon is read in mRNA in a continuous fashion

3. Three condoms function as stop codons

4. The initiator codon AUG codes for methionine.

1. 1,2 and 4 are incorect
2. 1, 2 and 3 are incorect
3. 2, 3 and 4 are incorect
4. 2 alone is correct
5. 1 alone is incorrect.

Answer: 5. 1 alone is incorrect.

Gene Regulation Recommended MCQs Question 151. The collection of cloned DNA segments obtained from the complete genome is called :

1. DNA library
2. Genomic bank
3. Gene bank
4. Both 2 and 3

Answer: 4. Both 2 and 3

Question 152. In the operon model, the regulator gene functions as :

1. Regulator
2. Inhibitor
3. Repressor
4. Stimulator.

Answer: 3. Repressor

Question 153. Genes involved in turning on and off of structural genes are:

1. Operator genes
2. Regulator genes
3. Redundant genes
4. Promoter genes.

Answer: 2. Regulator genes

Question 154. Lac operon is related to :

1. Synthesis of enzymes for lactose catabolism
2. Synthesis of enzymes for lactose anabolism
3. Synthesis of lac by lac insects
4. Degradation of lac by lac insects.

Answer: 1. Synthesis of enzymes for lactose catabolism

Question 155. According to the operon concept, the regulator gene regulates chemical reactions in the cell by :

1. Inactivating enzyme in the reaction
2. Inhibiting the substrate in the reaction
3. Inhibiting transcription of m-RNA
4. Inhibiting the migration of mRNA into the cytoplasm.

Answer: 3. Inhibiting transcription of m-RNA

Question 156. The modem concept of a gene is that it is :

1. A segment of DNA
2. A segment of chromosome
3. A functional unit of DNA
4. All of these

Answer: 3. A functional unit of DNA

Question 157. SV 40 has five genes but the type of proteins synthesized by it is more than twice the number of genes present in it. It shows the presence of:

1. Contained genes
2. Split genes
3. Overlapping genes
4. Degenerate genes.

Answer: 3. overlapping genes

Question 158. Provirus differs from prophage about:

1. Integration of RNA with host DNA
2. Integration of genetic DNA with host DNA
3. Integration of copy DNA of retrovirus with host DNA
4. None of the above.

Answer: 3. Integration of copy DNA of retrovirus with host DNA

Question 159. Which virus has a rod-shaped structure?

1. Rheo viruses
2. Φ× 174
3. T phage
4. TMV.

Answer: 4. TMV.

Question 160. Tryptophan Operon is :

1. Repressible system
2. Inducible
3. Controlled by regulator gene
4. Made of 3 structural genes.

Answer: 1. Repressible system

Biomembranes And Cell Wall

The plasma membrane and intracellular membranes collectively constitute biological membranes.

• The plasma membrane surrounds each cell, defining its limits and maintaining essential separations between its internal components and the external environment. It exhibits selective permeability.
• Intracellular membranes partition the cell into functionally distinct compartments known as organelles, including mitochondria and chloroplasts.
• Biological membranes demonstrate selective permeability, permitting the passage of some molecules while inhibiting others.
• All biological membranes display dynamism.
• All biological membranes of eukaryotic cells have fundamental architecture, comprising lipids and protein molecules interconnected by non-covalent interactions.
• Chemical composition. The plasma membrane consists of 58% proteins, encompassing structural and functional proteins like permeases, and 40% lipids, mostly phospholipids, cholesterol, and galactolipids.
• Minor polymers of monosaccharides (L-27%) form weak interactions with proteins and lipids.

Function and Structure of Cell Wall Membrane For NEET Models Of The Structure Of Plasma Membrane

The plasma membrane under an electron microscope appears to be trilaminar. Davson and Danielli put forward the Lamellar model which states that it is formed of four layers i.e. two proteins and two phospholipids. J.D. Robertson gave the concept of unit membrane which means that all membranes have three layers with a phospholipid bilayer sandwiched between two layers of proteins.

Read and Learn More NEET Biology Notes

According to the unit-membrane concept, all cell membranes possess a common basic structure, consisting of two layers of proteins and a middle bilayer of lipids. According to the fluid-mosaic model, the lipids and proteins are managed in a mosaic fashion in the membrane.

The cell membrane possesses a quasi-fluid phospholipid layer with embedded proteins. These impart considerable fluidity to the membranes.

Singer and Nicholson proposed a Fluid mosaic model. According to this model, phospholipids are arranged in a bimolecular layer with their hydrophilic polar heads forming outer surfaces and hydrophobic non-polar tails buried in the membrane.

The proteins are extrinsic and intrinsic. The plasma membrane is in the form of quasi-fluid. It also explains the permeability of carrier proteins.

Detailed Notes On Cell Wall And Cell Membrane Structure For NEET

Specialization of the plasma membrane. Various modifications are formed to perform special functions. They are microvilli. The adjacent cells may develop specialized structures such as interdigitations, desmosomes, intermediary junctions, and tight junctions.

Functions. lt provides shape and protects the contents inside the cell.

It controls permeation and has the property of retentivity. It binds the semifluid cellular constituents. It also acts as a barrier between protoplasm and the external environment. It possesses properties of permeability, and surface tension and is electrically charged.

Function and Structure of Cell Wall Membrane For NEET Flow Of Materials

To perform the various life activities, the cell must exchange certain substances with the environment.

It is necessary that metabolic essentials such as oxygen mineral salts and nutrients must get into the cell and waste products such as ammonia, COr, calcium crystals, and other metabolites, must pass out of the cell.

All these exchanges can take place only through the cell membrane by many processes as follows:

1. Passive transport
   • Diffusion
   • Osmosis
2. Facilitated diffusion
3. Active transport
4. Na+ and K+ exchange Pump
5. Endocytosis
   • Phagocytosis
   • Pinocytosis
6. Exocytosis

Transport of materials takes place across the membranes by two major processes-

Passive Transport and Active Transport. Passive transport is a physical process that neither requires energy nor oxygen for the transport of substances by the cell. This includes diffusion and osmosis’

Diffusion. The physical process involves the transport of materials from a region of higher concentration to a region (solutes and gases) of lower concentration and pressure respectively to spread uniformly.

Facilitated diffusion. A substance first combines with the carrier protein without the use of energy in the cell membrane and then it diffuses across the membrane.

The diffusion rate can be expressed by the formula:

Diffusion rate = Concentration difference x Cross-sectional area x Temperature/\tlolecular

weight x Distance x Density of Medium.

Osmosis. Bulk flow of water through a semipermeable membrane into another aqueous phase containing a solute in higher concentration Osmotic pressure.

Pressure is generated by the osmotic flow of water through a membrane into an aqueous phase containing a solute in higher concentration.

Important Questions On Cell Wall And Cell Membrane For NEET Exam

Plasmolysis. A plant cell when placed in hypertonic solution undergoes the shrinkage of its cytoplasm with plasma membrane.

Plants can absorb water through osmosis Active transport is an energy-dependent process.

A membrane protein acts as a carrier that binds and transports the molecule or ion in a specific direction across the membrane It even takes place against an electrochemical gradient.

In sodium-potassium exchange pump Na+ – K+ ATPase actively transports three molecules of Na+ outwards and two molecules of K+ inward.

Endocytosis. Intaking of large-sized liquid or solid macromolecules inside the cell through the plasma membrane.

Exocytosis. (cell vomiting). Expelling of cellular secretions of gland cells or wastes out of the cell through the plasma membrane.

Phagocytosis (cell-eating). Ingestion of solid particles by the cell Phagocytosis is of two kinds viz.

Colloidopexy: In this case plasma membrane ingests small colloidal particles as shown by leucocytes and macrophage cells of mammals.

Chromopexy Colloidal chromogen particles are ingested by plasma membrane as shown by mesoblastic cells of mammals.

Pinocytosis is the process of endocytosis in which liquid food is engulfed in bulk through a plasma membrane.

Plant cells possess cell walls and this feature distinguishes them from animal cells.

The cell wall is partially non-living and partially living structure. It is secreted by cytoplasm or protoplast. It has a supportive and protective function.

There are three distinct layers -middle lamella, primary cell wall, and secondary cell wall. Occa- a tertiary cell wall may be present.

‘u’ Middle lamella is a cementing layer between the primary walls of adjacent cells. It is composed of pectin, calcium, and magnesium. During the ripening of fruits enzyme pectinase dissolves it.

The primary cell wall is 0.1pm thick. It is composed of chiefly cellulose, hemicellulose, and pectic compounds. Cellulose fibrils are made up of 8,000 to 12,000 glucose units, they are about 1004 in diameter.

The secondary wall is laid down inner to the primary wall. It is 5 to 10 pm thick.

The secondary cell wall has three layers- outer layer, middle layer, and inner layer. The primary wall has small pores called plasmodesmata which connect the cytoplasm of adjacent cells. The cell wall is made up of matrix and microfibrils.

Molecular organization. The cell wall appears to consist of a gelatinous amorphous matrix consisting of polysaccharides (mainly pectin), gums, tannins, silica, and wax.

In the matrix are found many fibrils called microfibrils. 0.5 pm in width visible under a light microscope. The microfibril consists of bundles of 250 each, which is about 250 i in diameter. It is visible under an electron microscope.

The microfibril in turn consists of bundles of micelles elementary fibrils each about 100 i in diameter. The micelle contains about 100 cellulose chains.

Each microfibril is lpm long and 100-250 i in diuter. Each microfibrilconsists of 20 micelles. Each micelle consists of 100 individual cellulose chains. Each cellulose chain consists of 3000 – 6000 glucose molecules linked by B 1-4 linkage and is unbranched.

Origin. The cell wall is laid during the telophase stage of cell division from vesicles of the Golgi complex or E.R.

Function. The cell wall is a highly active region as many enzymatic activities are known to occur. In addition to providing shape and strength, it protects the cell organelles and plays a vital role in cell expansion. It helps in the transport of materials and metabolites in and out of the cell and encounters the turgor pressure developed inside.

• Most of the prokaryotic cells particularly bacterial cells, have a chemically complex cell envelope. Its layers are stacked upon one another.
• The outermost layer is glycocalyx followed by cell wall and cell membrane (plasma membrane).
• Glycocalyx. Any coat present outside the plasma membrane is called a cell coat. It forms a cell wall in plant cells and a pellicle in prokaryotes. In animal cells polysaccha- rides form the external cell coat or glycocalyx. This layer of glycocalyx differs in thickness and chemical composition in different bacteria. Some have a loose sheath called a slime layer which protects the cells from loss of nutrients and water. Some others have a tough covering called the capsule.
• In bacterial cells, the cell coat is formed of a protein-lipid polysaccharide complex.
• Bacteria can be classified according to their ability to take up and retain certain dyes.
• Gram staining is the most widely used staining procedure.
• The gram staining technique divides most bacteria into one or two groups.
• A Danish physician, Dr. Hans Christian Gram developed this staining method in 1884 to distinguish between the bacteria that cause pneumonia and eukaryotic cell nuclei in infected mammalian tissues.
• Differences between Gram-positive and Gram-negative Bacteria
• In Mycobacterium and Noccardia, the wall is of Gram-positive type but a part of their cell wall is made up of a very long chain of fatty acid called mycoic acid.
• Differences between pilus and fimbriae The Primary cell wall in plant cells is composed of an intricate network of microfibrils in a gel-like matrix arranged in cellulose microfibrils, pectic polysaccharides, and structural proteins.
• A new class of protein called expansion is responsible for wall loosening and cell expansion by the addition of cellulose molecules to cellulose microfibrils.
• The matrix of the wall contains water, pectin, hemicellulose, and glycoproteins. Pectin is the filler substance of the matrix. It is a mixture of polymerized and methylated galacturans, galacturonic acid, and neutral sugars.
• Glycoproteins control the orientation of microfibrils. They also exert enzymatic influence on the metabolic activities of the wall. Hemicellulose is a mixture of polymerized xylans, mannans, glucomannans, galactans, and arabinogalactans. It binds microfibrils with the matrix.
• The phospholipids and integral proteins of the plasma membrane are amphipathic. The term was coined by Hartley in 1936 for those molecules which have both hydrophobic and hydrophilic groups.
• The flexibility of the cell membrane is due to the presence of fatty acid contents. This enables bacteria to maintain the same fluidity over a temperature range of almost 100. c.
• The proteins are not easily extricated from the membrane because of their high degree of insolubility and non-covalent bonds.
• The plasmodesmata help in maintaining the continuity of living matter and cytoplasm, such condition is called sym-plasm. In contrast to this, the intercellular space containing non-living matter is called apoplasm.

Cell Wall And Cell Membrane Structure NEET Important Diagrams

Quanta To Memory

• Membrane-less cell organelles include ribosomes, centrioles, centrosomes, nucleoli, microtubules, microfilaments, chromosomes, and intermediate filaments.
• Cell organelles characterized by a single membrane: lysosomes, Golgi apparatus, endoplasmic reticulum, thylakoids, peroxisomes, protoplasts, vacuoles, glyoxisomes, flagella, and cilia.
• Cell organelles have a double membrane: plastids, mitochondria, nucleus.
• Cell organelles possessing many membrane layers exceeding two.
• Tranosome — three membrane encasement.
• The plastids of Euglenoids and Dinoflagellates possess three membrane layers.
• Diatom plastids possess four membrane layers.
• The typical thickness of the plasma membrane is from 70 to 100 Å, but the plasma membrane of red blood cells measures 215 Å.
• The dimensions of molecules capable of traversing the plasma membrane range from 1 to 15 angstroms.
• The nuclear membrane creates outpockets that are constricted to produce blebs or vesicles, a phenomenon known as blebbing, as reported by Gay in Drosophila.
• The most intricate glycolipids are gangliosides, which incorporate one or more sialic acid residues, also referred to as N-acetyl neuraminic acid (NANA). It imparts a negative charge to the cell membrane.
• Glycoproteins facilitate cellular recognition. A membrane is predominantly maintained by hydrophobic interactions.
• The glycocalyx is an extracellular coating located outside the cell membrane in animal cells. It comprises oligosaccharides linked to lipids and proteins, resulting in glycolipids and glycoproteins. It serves a protective function and operates as a recognition hub.
• Lipid-soluble compounds traverse the plasma membrane more easily than water-soluble molecules.
• Protein-free lipid bilayers exhibit impermeability to ions while allowing unrestricted permeability to water.
• The secretion of neurotransmitters by neurons exemplifies exocytosis.
• Seagulls and penguins excrete NaCl via nasal glands containing Na+ – K+ pumps.
• Younger cells possess thinner and elastic (semi-rigid) cell walls to facilitate growth by intussusception.
• Meristematic, parenchymatous cells, and root hairs possess solely primary cell walls

Matrix is an amorphous, gel-like material. It has watery hemicellulose and pectin but also has lipids and protein. Hemicellulose is made of:

• Arabinose
• Mannose
• Pectin consists of glucuronic acid and galacturonic acid units.
• The tertiary wall is made of cellulose and xylan.
• Plasmodesmata are inner cytoplasmic strands.
• Ca++ cross-links play a role in holding cell wall components together.
• The cell wall is permeable as spaces of framework allow free passage of dissolved materials between cells and their environment. The cell coat is different from the cell wall.
• Water moves passively through the apoplast which gives thermo- charge.
• Messenger recognition sites of two neighboring cells may bind to each other causing cell adhesion.
• Glycophorin is present in the membrane of RBC.
• In Immune responses of various response systems, glycoproteins act as antigens.
• Lipid molecules have kinks in fatty acid tails which prevent the close packing of molecules and make the membrane structure more fluid. Fluidity increases, decreasing the length of fatty acid tails. Kinks are due to double bonds in the tail.
• Carbohydrates are attached to the polar side of the lipid to form Glyeolipid 1 he lipid: Protein ratio in some eases aw as under
  • 40: 60
  • 35: 65
  • 42: 58
  • 76: 24

Functions of proteins in Plasma membrane

• Transporters of molecules across cellular membranes.
• Receptors. Information transfer within cells.
• Enzymes. Each membrane contains enzyme molecules designated for specific cellular functions.
• The plasma membrane does not permit the escape of the cell’s contents, as it retains its color due to the presence of pigment molecules.
• Gases have the highest rate of diffusion. Ions and diminutive polar molecules disperse at a sluggish rate. Fat-soluble molecules have the highest rate of passage.
• Daniel and Davson’s model was proposed prior to the observation of the plasma membrane using an electron microscope.
• The fluid mosaic concept posits that the bilayer of phospholipid molecules acts as a relatively impermeable barrier to the transit of most water-soluble substances.
• It is proposed that water exists within the plasma membrane. In the absence of water, how do lipids develop hydrophilic and hydrophobic regions? Only recommended
• Plasma membrane organelles perform analogous activities due to their fundamental structural similarities. Nonetheless, many membranes exhibit numerous structural and physicochemical functional disparities.
• The ratio of lipids to proteins ranges from 1:08 to 1:4. The unit membrane idea cannot be applied unconditionally.
• The lignified wall is colored with safranin. The cell wall is lacking in mycoplasma, gametes, and animal cells.

NEET Biology Cell Structure and Function MCQs

Question 1. Engulfing of food materials or foreign bodies is called:

1. Pinocytosis
2. Pinocytosis and phagocytosis
3. Mitosis
4. Phagocytosis.

Answer: 4. Phagocytosis.

Question 2. The total thickness of the plasma membrane proposed by Robertson is:

1. 5Å to 20Å
2. 20Å to 35Å
3. 50Å to 75Å
4. 75Å to 100Å

Answer: 4. 75Å to 100Å

Question 3. The main function of the plasma membrane is to :

1. Regulate the flow of material into and outside the cell
2. Maintain the cell shape and size
3. Control all cellular activities
4. Store cell material.

Answer: 1. Regulate the flow of material into and outside the cell

Question 4. In a fluid mosaic model of the cell membrane, the extrinsic proteins are :

1. Attached to intrinsic proteins but can be separated easily
2. Superficially present but cannot be separated easily
3. Superficially present and can be easily separated
4. Attached to intrinsic proteins but cannot be separated easily.

Answer: 3. Superficially present and can be easily separated

Question 5. The one end of the phospholipid in the cell wall of plants is hydrophobic, which means:

1. It has no affinity for metabolites
2. It has no affinity for water
3. It has no affinity for solutes
4. None of the above.

Answer: 2. It has no affinity for water

Question 6. Amoeba, a single-celled organism, has a specialized structure called a contractile vacuole whose function is to collect excess water frorn the cell and discharge the water into the environment. From this infor-mation you can deduce that amoeba live in an environment that is (hypotonic) to the interior solution of amoeba. Thus, you would expect to find amoebas living in :

1. A freshwater pond
2. The ocean
3. Great salt lake
4. A bottle of unpasteurized milk.

Answer: 1. A freshwater pond

Question 7. We know that the Golgi body discharges substances from the cell by fusing of vesicles with the plasma membrane and subsequent opening of what was the interior of the vesicle to the outside environment. This is an example of:

1. Exocytosis
2. Endocytosis
3. Active transport
4. Facilitated diffusion.

Answer: 1. Exocytosis

Question 8. The selective transfer of particles through the cell membrane is an important factor in the process of:

1. Cytoplasmic streaming
2. Homeostasis
3. Nuclear transfer
4. Mechanical digestion.

Answer: 2. Horneostasis

Question 9. The plasma membrane consists of three layers arranged :

1. Protein layer, phospholipid layer, and protein layer
2. The phospholipid and two protein layers
3. The two protein layers and the phospholipid layer
4. The protein layer, the phospholipid layer, and the fat layer.

Answer: 1. Protein layer, phospholipid layer, and protein layer

Question 10. The bordered pits are characteristics of:

1. Ferns
2. Gymnosperms
3. Angiosperms
4. Cycads.

Answer: 2. Angiosperms

Question 11. The torus of simple and bordered pits is made up of :

1. Suberin
2. Glttcose
3. Cutin
4. Phospholipids.

Answer: 1. Suberin

Question 12. Membrane functions are carried out by :

1. Carbohydrates
2. Lipids
3. Metalion
4. Proteins.

Answer: 4. Proteins

Question 13. The integrity of the membrane is maintained by :

1. Ionic bonds
2. Covalent bonds
3. Hydrophilic action
4. Hydrophobic attractions.

Answer: 3. Hydrophilic action

Question 14. According to the fluid mosaic model, the fluidity of a cell membrane is due to :

1. Lipid
2. Proteins
3. Glycoproteins
4. Glycolipids.

Answer: 1. Lipid

Question 15. Regarding cellular membranes one of the following is incorrect?

1. Membranes are selectively permeable but a solute’s electrical polarity and other physical characteristics may affect its ability to enter or leave.
2. Water-soluble substances pass through more rapidly than lipids and lipid-soluble substances.
3. Generally smaller molecules pass through cellular membrane more readily than larger molecules.
4. None of the above.

Answer: 2. Water-soluble substances pass through more rapidly than lipids and lipid-soluble substances.

Question 16. The counter pressure exerted by the cell wall tends to oppose :

1. Turgor pressure
2. Osmotic pressure
3. Solvent pressure
4. Diffusion pressure.

Answer: 1. Turgor pressure

Question 17. Ion channels have been discovered by :

1. Singer and Nicholson
2. Nehar and Sakmann
3. Gamier
4. Robinson and brown.

Answer: 2. Nehar and sakmann

Question 18. The most abundant lipid in a cell membrane is:

1. Phospholipid
2. Cholesterol
3. Steroid
4. Cutin.

Answer: 1. Phospholipid

Question 19. Glycoproteins are known to play an important role in cell recognition. The specificity of this recognition is provided by:

1. Lipid portion of glycoproteins
2. Lipids are in the least proportion
3. Oligosaccharide portion of glycoprotein
4. Proteins are in the least proportion.

Answer: 3. Oligosaccharide portion of glycoprotein

Question 20. According to the fluid mosaic model, which one is true?

1. Oligosaccharides and lipids are held by non-covalent interaction
2. Components of the plasma membrane can be dispersed by detergents
3. Lipids and proteins are amphoteric
4. Polar groups of proteins are directed towards the lipid bilayer.

Answer: 4. Polar groups of proteins are directed towards the lipid bilayer.

Question 21. When a group of cells is placed in a salt solution whose concentration is more than their cell sap :

1. The cytoplasm with its plasma membrane expands
2. The cytoplasm with its plasma membrane shrinks up
3. The cytoplasm comes out through the plasma membrane
4. The cytoplasm remains in position.

Answer: 2. The cytoplasm with its plasma membrane shrinks up

Question 22. Which of the following structures of the cell is dead?

1. Cell wall
2. Nucleus
3. Plasma membrane
4. Mitochondria.

Answer: 1. Cell wall

Question 23. An Electron microscope has revealed that the cell wall is made up of several layers of :

1. Cavities
2. Microfibrils
3. Plasmodesmata
4. Myonemes.

Answer: 2. Microfibrils

Question 24. Plasmalemma prevents escape of na+ and k+ to :

1. Disrupt neighboring cells through desmosomes
2. Maintain electrostatic neutrality of cells
3. Maintain cell sap
4. All of the above.

Answer: 1. Cause disruption in neighboring cells through desmosomes

Question 25. The cell wall is a permeable membrane can be best deducted from the passage of water and mineral salts from:

1. The root hair into cortical cell
2. The pericycle cells into the tracheal elements
3. The cortical cells are into tracheal elements
4. The soil into the root hair.

Answer: 4. The soil into the root hair.

Question 26. In the fluid mosaic membrane model, the phospholipid bilayer:

1. Is sandwiched between two protein layers
2. Have proteins embedded in it
3. Lies on top of a single protein
4. Is covered by a single protein.

Answer: 2. Has proteins embedded in it

Question 27. The structure in the ce1l bounded by the single membrane is :

1. Chloroplast
2. Peroxisome
3. Ribosome
4. Mitochondria.

Answer: 2. Peroxisome

Question 28. Plasma membranes of adjacent cells become thicker at certain regions. They are called :

1. Desmosomes
2. Terminal bars
3. Infoldings
4. None of the above.

Answer: 1. Desmosomes

Question 29. The middle lamella is made up of :

1. Protein
2. Cellulose
3. Calcium and magnesium pectate
4. Lignin.

Answer: 3. Calcium and magnesium pectate

Question 30. The cell wall in plants is composed of :

1. Chitin
2. Lipids
3. Xylan
4. Cellulose.

Answer: 4. Cellulose.

Question 31. The cellulose layer during the formation of the cell wall is secreted by the outer cytoplasm as :

1. Primary wall
2. Secondary wall
3. Tertiary wall
4. None of the above.

Answer: 1. Primary wall

Question 32. All membrane processes, such as pumping and channeling of molecules are carried out by :

1. Lipids
2. Carbohydrates
3. Nucleic acids
4. Proteins.

Answer: 4. Proteins.

Question 33. Plant cells can usually be distinguished from animal cells because only plant cells possess:

1. Cell wall and mitochondria
2. Goigi bodies and central vacuole
3. Celt wall and central vacuole
4. Chromosome and mitochondria.

Answer: 3. Celt wall and central vacuole

Question 34. If you were given a non-polar- membrane, which of the following would you expect to diffuse through it with the most ease :

1. CO2 phenylalanyl
2. Glycine
3. Lead atom
4. Proteins.

Answer: 1. CO2 phenylalanyl

Question 35. Membranes are found within :

1. Cytoplasm, chloroplasts and mitochondria
2. Chromosomes, nuclei, and mitochondria
3. Cytoplasm, nuclei, and starch grains
4. Chromosomes, chloroplasts, and starch grains.

Answer: 1. Cytoplasm, chloroplasts and mitochondria

Question 36. Which of these factors affects the movement of substances through the plasma membrane?

1. Permeability of the membrane
2. Size of diffusing particles
3. Membrane proteins
4. A1l the above.

Answer: 4. A1l the above.

Question 37. Endocytosis refers to :

1. Phagocytosis
2. Pinocytosis
3. Phagocytosis and pinocytosis
4. Mitosis.

Answer: 3. Phagocytosis and pinocytosis

Question 38. The plasma membrane is selectively permeable. It shorts maximum permeability to:

1. K+
2. Nh4+
3. Na+
4. Ca++

Answer: 1. Nh4+

Question 39. Pinocytosis and active transport are similar because both processes:

1. Depends directly upon cyclosis within a cell
2. Require the expenditure of energy
3. Are types of circulation
4. Increase the absorbing surface of- cell.

Answer: 2. Require the expenditure of energy

Question 40. Most living cells acquire unwanted compounds either by absorption from their surroundings or as by-products of chemical activities. Cells would die if such compounds are accumulated in the cytoplasm or nucleus. Hence mechanisms have evolved to affect their removal. It is accomplished by developing a system of:

1. Membranes such as endoplasmic reticulum
2. Pores in the mernbrane of nucleus
3. Semipermeable cell membrane surrounding the nucleus
4. Vacuoles.

Answer: 2. Pores in the membrane of the nucleus

Question 41. The term osmosis refers to the diffusion of :

1. Energy
2. Water
3. Glucose
4. Positive electric charges.

Answer: 2. Water

Question 42. The function of the intracellular membrane is to:

1. Establish several compartments within the cell
2. Provide the neat spatial organization of enzymes and pigments
3. Provide a system of channels for the distribution of nutrients within cell
4. All the above

Answer: 4. All the above

Question 43. Amphipathy means:

1. Presence of hydrophobic and hydrophilic groups in the same molecules.
2. Hydrophobic
3. Hydrophilic
4. Isotonic.

Answer: 1. Presence of hydrophobic and hydrophilic groups in the same molecules.

Question 44. An import of energy is required for which of the following:

1. Diffusion
2. Osmosis
3. Facilitated diffusion
4. Active transport.

Answer: 4. Active transport.

Question 45. Microvilli are :

1. Finger-like projections on cell surface responsible for ultra absorption of liquids.
2. Finger-like projections of nuclear membrane responsible for obtaining nutrients for the nucleus
3. Hair-like structures on the cell surface responsible for the sense of touch
4. Secondary finger-like projection on the intestinal villi.

Answer: 1. Finger-like projections on cell surface responsible for ultra absorption of liquids.

Question 46. The simplest and most common mechanism by which substances move across the cell wall is:

1. Active transport
2. Metabolically coupled transport
3. Diffusion
4. Osmosis.

Answer: 3. Diffusion

Question 47. Continuity of cytoplasm from cell to cell is maintained through:

1. Middle lamella
2. Plasmodesmata
3. Endoplasmic reticulum
4. Cell membrane system.

Answer: 2. Plasmodesmata

Question 48. Which pair of structures are usually found in both plant and animal cells?

1. Cell membrane and nucleolus
2. Cell membrane and cell wall
3. Nucleolus and chloroplast
4. Nucleus and cell wall.

Answer: 1. Cell membrane and nucleolus

Question 49. Tonoplast is a differentially permeable membrane surrounding the:

1. Mitochondria
2. Cytoplasm
3. Vacuole
4. Nucleus.

Answer: 3. Vacuole

Question 50. Singer and Nicholson model of plasma membrane differs from Robertson’s model in the :

1. Arrangement of lipid layers
2. Arrangement of proteins
3. Absence of proteins in the Singer model
4. Number of lipid layers.

Answer: 2. Arrangement of proteins

Question 51. Which of the following does not pass across membranes by simple diffusion?

1. O2
2. H+
3. Co2
4. H2O.

Answer: 2. CO2

Question 52. All are membrane-bound cell organelles except:

1. Sphaerosome
2. Lysosome
3. Ribosomes
4. Chloroplast.

Answer: 3. Ribosomes

Question 53. Sialic acid is a constituent of:

1. Cell membrane
2. Cell wall
3. Tonoplast
4. Chromosome.

Answer: 2. Cell wall

Question 54. Beetroot does not lose color in freshwater This is because :

1. The plasma membrane is permeable
2. The plasma membrane is impermeable to pigment
3. The plasma membrane and cell wall are permeable
4. Both the plasma membrane and cell wall are impermeable.

Answer: 2. Plasma membrane is impermeable to pigment

Question 55. Cellulosic cell walls can be specifically stained by

1. Zinc chloride
2. Phloroglucinol
3. Methyl blue
4. Sudan 4.

Answer: 1. Zinc chloride

Question 56. The plan of cell wall formation is determined by:

1. Golgi bodies
2. Er
3. Microtubules
4. Nucleus.

Answer: 1. Golgi bodies

Question 57. Which of the following is not a form of endocytosis?

1. Monocytosis
2. Phagocytosis
3. Pinocytosis
4. Receptor-mediated cytosis.

Answer: 1. Monocytosis

Question 58. The process by which a cell secretes macromolecules by fusing a transport vesicle to a plasma membrane is:

1. Pinocytosis
2. Endocytosis
3. Phagocytosis
4. Exocytosis.

Answer: 4. Exocytosis.

Question 59. Membrane potential is caused by unequal distribution

1. Ions
2. Isotopes
3. Fatty acids
4. Glucose

Answer: 1. Ions

Question 60. The cell wall is the secretion of:

1. Middle lamella
2. Plasmalemma
3. Cytoplasm
4. Plasmodesmata

Answer: 3. Cytoplasam

Question 61. The cell wall is thin in :

1. Xylem
2. Collenchyma
3. Cytoplasm
4. Parenchyma.

Answer: 4. Parenchyma.

Question 62. Animal cells do not have cell walls because:

1. They are adapted to move their body
2. They have muscles and nerves
3. They have to change the size of their body during locomotion
4. All correct.

Answer: 4. All correct.

Question 63. The smallest structural unit of the cell wall is :

1. Fibril
2. Microfibril
3. Micelle
4. Middle lamella.

Answer: 3. Micelle

Question 64. Unripe fruits are hard, due to :

1. Tannins in the cell wall
2. Middle lamella
3. Plasmodesmata
4. All of these.

Answer: 2. Middle lamella

Question 65. The cell wall in bacteria and cyanobacteria is made up of :

1. Murein or mucopeptide
2. Peptidoglycan and amino sugars
3. Cellulose
4. Chitin.

Answer: 2. Peptidoglycan and amino sugars

Question 66. The hemicellulose in the cell wall acts as :

1. Filler substance
2. Binding microfibril
3. Strengthening cellulose
4. All of these.

Answer: 2. Binding microfibril

Question 67. A micelle is made up of :

1. 250 Microfibril
2. 100 Cellulose chains
3. 20 Macrofibrils
4. 3000 Cellulose chains.

Answer: 2. 100 Cellulose chains

Question 68. Mineral elements of the middle lamella are/are :

1. Calcium pectate
2. Magnesium picrate
3. Manganese
4. Both 1 and 2.

Answer: 4. Both 1 and 2.

Question 69. The cell wall of the fungus contains :

1. Pectin and cellulose
2. Cellulose and chitin
3. Chitin and pectin
4. Chitin and silica.

Answer: 2. Cellulose and chitin

Question 70. Torus is related to:

1. Bordered pits in the cell wall
2. Receptacle of lotus
3. Both correct
4. Both wrong.

Answer: 3. Both correct

Question 71. Symplast:

1. Is the living component of the cell
2. Consists of cytoplasm and cell membrane
3. Both correct
4. Only 2 Is correct.

Answer: 3. Both correct

Question 72. The cell wall is absent in some plant cells like:

1. Zoospores
2. Gametes
3. Pplo
4. All correct.

Answer: 4. All correct.

Question 73. Intussusception is shown by a primary cell wall. It is :

1. Deposition of cell wall materials from inside to cause growth
2. Deposition of wall materials from outside as layers
3. Hardening of cell wall
4. None of these.

Answer: 1. Deposition of cell wall materials from inside to cause growth

Question 74. A pit is an unthickened area in the cell wall. It lacks:

1. Primary wall
2. Middle lamella
3. Secondary wall
4. Cell wall and cell membrane.

Answer: 3. Secondary wall

Question 75. The term cell membrane was given by :

1. Nageli
2. Singer and Nicholson
3. Robertson
4. Plower.

Answer: 1. Nageli

Question 76. The main amino acids in the cell membrane are :

1. Arginine and lysine
2. Arginine and leucine
3. Arginine and tryptophan
4. Arginine and glycine.

Answer: 1. Arginine and lysine

Question 77. Carbohydrate molecules attached to lipid and protein molecules from glycocalyx (extraneous coat). These carbohydrates are usually :

1. Monosaccharides
2. Polysaccharides
3. Oligosaccharides
4. Starches.

Answer: 3. Oligosaccharides

Question 78. Fluid mosaic model explains :

1. A bilipid layer in between 2 protein layers
2. A layer of proteins on one side and a bilayer of lipids on the other side
3. 2 Lipid layers and 1 protein layer
4. A phospholipid layer with proteins between and on both sides of the lipid layer.

Answer: 4. A phospholipid layer with proteins between and on both sides of the lipid layer.

Question 79. Cellular recognition and adhesion are facilitated by components in plasmalemma. These are :

1. Lipids
2. Proteins
3. Both a and b
4. Glycolipids and glycoproteins.

Answer: 4. Both a and b

Question 80. The plasma membrane of an animal cell is composed of:

1. Lipids, proteins, oligosaccharides
2. Lipids, proteins, proteins, polysaccharides
3. Lipids, proteins, disaccharides
4. Lipids, proteins, monosaccharides.

Answer: 1. Lipids, proteins, oligosaccharides

Question 81. Na+- k+ pump is found in membranes of many cells like nerve cells. It works against an electrochemical gradient and involves an integral protein ATPase. For each molecule of ATP used :

1. 3 Ions of na+ are pumped out and two k+ ions are taken
2. 3 Ions of na+ are taken in and 2k+ are pumped out
3. 2 Ions of na+ are thrown and 3k+ are absorbed
4. 3 Ions of Na+ are pumped out.

Answer: 1. 3 Ions of na+ are pumped out and two k+ ions are taken

Question 82. The cell membrane shows maximum permeability :

1. K+
2. Nh4+
3. Na+
4. Ca++.

Answer: 1. K+

Question 83. Who among the following proposed unit membrane model for cell membrane?

1. Davson and Danielle
2. Robertson
3. Singer and Nicholson
4. Metchnikoff.

Answer: 2. Robertson

Question 84. The cell membrane is absent in :

1. Sperm
2. Bacteria
3. Lysosomes
4. None of these.

Answer: 4. None of these.

Question 85. Which process requires energy?

1. Bulk transport
2. Pinocytosis
3. Exocytosis
4. All of these.

Answer: 4. All of these.

Question 86. Pinocytosis was first reported by Edward in Amoeba. It is absent in:

1. Bacteria
2. Blue-green algae
3. Prokaryotes
4. All of these.

Answer: 4. All of these.

Plant Anatomy (Meristem Plant Tissues Anatomy Of Root Stem And Leaf)

Meristem

Meristem. A meristematic tissue consists of a group of cells which have the power of division. The word meristem lias its origin from the Greek word ‘meristos’ which means divisible. (Nageli, 1058)

C

They comprise isodiametric immature cells that are undergoing division and expansion.

• They are densely organized to eliminate intercellular gaps.
• The cells are predominantly spherical and possess slender walls encasing them.
• Each cell comprises a conspicuous nucleus and thick protoplasm.
• Vacuoles in the cell are typically missing; when present, they are rather tiny.
• During cell division, the initial nucleus undergoes mitotic division into two nuclei, followed by cytokinesis, culminating in the production of two daughter cells.
• Proplastids are present in lieu of plastids.
• Metabolic activity is elevated.
• The cambium cells are elongated and contain vacuoles.

Read and Learn More NEET Biology Notes

Anatomy of Flowering Plants for NEET

Anatomy Of Flowering Plants Neet Notes

1. Types Of Meristem Based On Development It is of three types :

1. Promeristem
2. Primary meristem
3. Secondary meristem.

• Promeristem. It is made up of a group of meristematic cells that represent the youngest stage of a growing organ. It is the earliest stage of the primary meristem.
• Primary Meristem. Promeristem gives rise to primary meristem. By the rapid cell divisions, the cells of primary meristem get differentiated into different tissues. Cells of this meristem divide in three or more planes.
• Secondary Meristem. It develops at a later stage in the development of an organ. It is always lateral in position.

2. Meristematic Tissue-Based On Function: The first formed meristem (Promeristem) gets differentiated into the following three regions :

1. Protoderm (gives rise to epidermis).
2. Procambium (gives rise to phloem, xylem and cambium).
3. Ground meristem (forms cortex, pericycle, medullary rays, pith, hypodermis and
   endodermis).

3. Types Of Meristem Based On Location The Body. According to location in the body meristems are of three types:

1. Apical meristems
2. Intercalary meristems
3. Lateral meristems.

• Apical Meristem. They are present at the apices of the stem, root and branches. These are responsible for increasing the length. Many cells form the apical meristems. However, in pteridophytes, one cell constitutes the meristem. It includes both pro-meristem and primary meristem.
• Intercalary Meristems: These are the parts of apical meristems, which get separated from the apex due to the development of permanent tissue in between. Intercalary meristems are found at the base of leaves above the nodes For Example. grasses, Equisetum, or below the nodes For Example. Mint. It increases the length of internodes and is finally consumed.
• Lateral Meristem. It is formed literally from the procambium strands i.e., cambium present between the xylem and phloem and the cork cambium of roots and stems. The cells divide only in the criminal plane and thus they add to girth. This type of meristem shows its activity after some time in plant organs.

4. Mcrislemulic Tissue-Based Oil Plane Of Cell Division:

• Mass Meristem. Here cells divide in all the planes thus increasing in volume. It can be noticed in the meristem of the cortex, pith etc.
• Plant Meristem. The cells divide in two planes. They form flat surfaces by increasing the area of organs For Example. Leaf formation.
• Rib Meristem. The cells divide only in one plane For Example., the formation of filaments in algae.

5. Based On Obesogens

• Dermatogen (forms piblcma and root cap in dicots),
• Periblem (forms cortex and endodermis), and
• Plcrome (forms pericyclic. vascular strand and pith.).

Anatomy of Flowering Plants – Important Notes for NEET Theories of Apical Meristem. Regarding the apical meristem, there are three theories:

1. Apical Cell Theory Was Formulated By Nagcli (1858). According to the apical cell theory or Nagcli ( 1858), the apical meristem is made up of a single apical cell in all plants. This is also called “Single-cell theory”.
2. Histogen Theory Proposed By Hanstein (1870). According to the history theory of Hanstein ( 1870), the apical meristem is divisible into three zones, i.e. outer dermatogen, middle problem and inner plenty. Dermatogen gives rise to epidermis, periblem to cortex and the pleronte to stele.
3. Tunica Corpus Theory Was Formulated By Schmidt (1924). According to the tunica corpus theory of Schmidt (1924), the apical meristem is made up of two zones i.e. tunica and corpus. The tunica zone is outer in position and its cells divide only anticlinally. On the other hand, the corpus zone is central in position and its cells divide in many planes. Tunicacorpus theory is the most accepted theory of apical meristem.
4. Korpe Kappe Theory (Schcupp, 1917). It deals with the organisation of the root apex, i.e. It has two parts. Kappe or cap and Korpe or body. Both show T-type division, upright or inverted.

Anatomy of Flowering Plants – Important Notes for NEET  Quiescent Centre

Clowes (1961) has shown the occurrence of an inactive centre in many roots called a quiescent centre. It is the region of low mitotic activity which occupies the central region of the root apex, For Example., between the root tip and meristem. In the quiescent centre, there is little synthesis of protein DNA and RNA.

The root apex is differentiated into 3 regions-

1. Protoderm (future epidermis),
2. Cortical initials (future cortex) and
3. Vascular cylinder. A group of initials at the apex produce cells on both sides.

Those towards the axis form the epidermis, cortex and vascular cylinder, while those away from the axis form the root cap. The Histogen involved in the formation of the cap (caiyptrogen) is derived from dermatogen.

Anatomy of Flowering Plants – NEET Questions Root Apex Initials

Neet Biology Anatomy Of Plants

They are arranged in the following four ways :

1. Ranunculus Type. There is a single set or layer of initials that gives rise to all parts.
2. Casuarina Type. Two sets or layers of initials-inner forming the central part, outer forming cortex, root cap and epiblema.
3. Common Dicot Type. Three sets or layers of initials, one forming root cap and epiblema, second cortex and third central cylinder.
4. Common Monocot Type. Four sets of initials, one (caiyptrogen) forming root cap, second epiblema, third cortex and fourth central cylinder.

Stem A place Meristem (Vetictatlve Shoot Apex)

It is a multicellular, dome-shaped or conical structure which is protected by young leaves produced by it. New leaves and axillary buds are produced periodically on the flanks.

• The period between the origin of two successive leaves is called plastoehron. The meristem forms three derivatives- protoderm (produces epidermis of stem and leaves).
• Procambium (forms vascular strand) and ground meristem (ground tissues like mesophyll of leaves, hypodermis, cortex. endodermis, pith, etc).

Anatomy of Flowering Plants – NEET Questions Permanent Tissue

Permanent Tissue. They are composed of mature cells which after undergoing complete growth, have assumed a definite shape, size and function. They have the power of division. Depending upon origin, permanent tissue is of two kinds:

1. Primary tissue consists of evils derived from the primary meristem and
2. Secondary tissue haring cells derived front secondary meristem.

The permanent tissue is of two types depending upon constitution i.e., simple tissue (one type of cells) and compound tissue (two or more than two types of cells.)

Kinds Of Simple Permanent Tissue.

• Parenchyma
• Collenchynta
• Sclerenchynta.

1. Parenchyma. Oval, spherical polygonal or isodiametric cells with thin cell walls. often with intercellular spaces.

• Parenchyma is modified into
• Chlorenehyma. These cells have chloroplasts and hence take part in photosynthesis. The Chlorenehyma of the leaf is called mesophyll. It is often differentiated into palisade parenchyma (columnar chlorenehymatous cells) and spongy parenchyma (irregular chlorenchyma cells enclosing air spaces),
• Aerenchyma. Network of star-like parenchyma cells enclosing large air cavities, For Example., aquatic plants.
• Epidermis. Cutinised parenchyma cells form a covering layer. A distinct layer of cutin or cuticle may occur on the outside,
• Guard Cells. They are a pair of specially thickened small reniform or dumb-bell cells which can create a pore in between them due to differential swelling,
• Prosenchyma. Elongated fibre-like parenchyma.

Anatomy of Flowering Plants – NEET Questions Parenchyma Functions

• The tissue takes pan in the storage of food, slow conduction and turgidity of softer pans.
• It is the major ground tissue that occurs inside the stem and root as cortex and pith, the pulp of the fruit.
• The endosperm of the seed, parts of vascular tissues, leaf interior, etc. The epidermis is made of modified parenchyma cells.

2. Collenchyma. The tissue of cells with thick cellulose cell walls, especially at the angles of the cells is called collenchyma. It is abundant in climbing stems. It occurs in the hypodermis of dicot stems and petiole.

Depending upon the place of thickening, collenchyma is of three types:

• Lamellate (Lamellar). Thickening on tangential walls For Example., the stem of a Sunflower,
• Lacunate. Thickening on the walls bordering intercellular spaces, For Example.. stem of Tagetes. Tomato. Datura.
• Angular. Thickening at the angles. For Example.. stem of Cucurbita.

Flowering Plant Tissue Structure Neet

Anatomy of Flowering Plants – NEET Questions Collenchyma Functions.

• It provides mechanical support.
• It provides elasticity while allowing plant organs to grow in size.
• The cells may store food as well as manufacture food.

3. Sclerenchyma. It is made up of hard and lignified tissue consisting of fibres and sclereids. Its function is also supportive.

1. There are two types of sclerenchyma cells
2. Long, flexible with tapered ends (fibres) and
3. Usually rough and spherical sclereids or stone cells.

Sclerenchymatous fibres. Individually, fibres are quite strong due to lignified walls. When these groups are together, their strength is greatly increased.

• Therefore, these can provide mechanical support to the tissue in which these are found. Fibres are commonly found in the pericycles of stems, forming a solid tissue protecting the vascular bundles of dicots.
• These also surround the vascular bundles of monocots and quite often, they form a layer in the cortex below the epidermis of stems or roots. These also occur in the xylem and phloem.

Anatomy of Flowering Plants – NEET Questions Sclerenchyma Commercial Fibres

1. Surface fibres For Example. cotton, calotropis, and coir (coconut).
2. Bast Fibres For Example. Hemp, Linum. Jute, Sun hemp.
3. Leaf Fibres For Example. Agave, Murs.

Steroids are usually singly or in groups in the plant body, especially in the phloem, fruit walls and in the pulp of fruits and seeds, Sclereids provide rigidity to the structures in Which these are found.

The graininess of the fruits like guava and pears is due to the occurrence of stone cells in soups in their pulp. The ssalls of sclereids are very’ thick, and highly lignified so that lumen is greatly reduced.

Sclerites-Sclereids occurring singly are called idioblastic sclereids or spicular cells or sclerites.

Anatomy of Flowering Plants – NEET Questions Sclereids Are Of The Following Five Types

1. Brachysdereids (Stone cells). Isodiametric sclereids resembling parenchyma in shape. found soft parts of plants.
2. Macrosdereids (rod cells or Malpighian cells). Columnar b shape, forming palisade-like epidermal layer b seed coats of peas and beans and epidermis of onion.
3. Osteosclereids (prop cells). Bone-like sclereids, columnar with dikted ends For Example. leaves and seed coat of many monocots. hr.
4. Astrosclereids-star-like (stellate) sclereids For Example. Nymphaea leaves, stem and leases of Thea. (tea).
5. Trichosclereids (or Trichoblasts or Internal hairs) are Long, hair-like, sometimes branched sclereids For Example. leaves of Olea and aerial roots of Monsiera.

Anatomy of Flowering Plants – NEET Questions Sclereids Functions

The function of sclerenchyma is to provide support and mechanical strength to the plant. Therefore, its distribution in plants is related to be physical stress which different organs have to face.

Sclereids Compound Tissue

Sclereids is two types, i,e. xylem and phloem.

Anatomy of Flowering Plants – NEET Questions Xylem

The xylem is a permanent complex conducting tissue. It is also called wood. It is concerned with the upward conduction of water and minerals.

Xylem is a group of cells which are similar b origin and function but of more than one type b structure. On be basis of development, the xylem consists of two primary xylem and a secondary xylem.

Primary Xylem. It is differentiated into :

1. Protoxylem. It is the first formed part and consists of annular and spiral tracheids and vessels.
2. Metaxylem. It is formed later and consists of scalariform, reticulate and pitted tracheids and vessels.

The Primary Xylem Is Of Three Types based on be relation between the protoxylem and metaxylem.

Three forms are:

1. Exarch.
2. Endarch
3. Mesarch

The secondary xylem is formed from vascular cambium during secondary growth. It may consist of annual rings. Each annual ring is made up of autumn wood and spring wood.

Anatomy of Flowering Plants – NEET Questions Elements Of Xylem

Xylem is composed of the following four different kinds of elements:

1. Tracheids
2. Vessels
3. Xylem parenchyma
4. Xylem fibres.

1. Tracheids. These are elongated (1-6 mm) tube-like dead single cells with hard, thick and lignified walls. Their end walls are tapered and overlap with adjacent tracheids. When mature, babies are dead with empty lumens.

Water can pass through empty lumens and passes from tracheid to tracheid through ‘pits’ in beer walls. However, angiosperms have relatively fewer tracheids, and vessels are more common b bese plants.

Anatomy of Flowering Plants – NEET Questions Depending Upon Thickenings, Tracheids Are Of The Following Type

1. Annular,
2. Spiral,
3. Reticulate,
4. Scalariform and
5. Pitted (simple pits or bordered pits).

2. Vessels. These are characteristic conducting units of xylem m angiosperms. These are very long (l-6m) tubular structures formed by be fusion of several cells (called vessel elements) end to end in a row.

The vessel elements are similar to tracheids, except bats are shorter and wider than be latter. Vessels are exceptionally long in Eucalyptus.

3. Xylem Parenchyma. Parenchymatous cells associated with the xylem together constitute the xylem parenchyma. The cells are living, thin-walled and abundant. These are mainly involved in the short-distance transport of substances as well as the storage of sugars, starch and lipids.

4. Xylem Fibres. Sclerenchymatous fibres present in the xylem are called xylem fibres. These occur abundantly in woody dicots. These do not conduct water. Thus, these have thicker walls and narrower lumens than xylem vessels and are, therefore, stronger and provide additional mechanical strength to the xylem.

Anatomy of Flowering Plants – NEET Questions Phloem

It is a permanent complex tissue. It is meant for the conduction of food materials. Phloem occurs throughout the plant body along with the xylem. Phloem is of three types based on its position i.e. External phloem present outside the xylem. Internal phloem present inner to xylem and Interxylary or included phloem present within the secondary xylem.

Phloem is made up of four types of cells :

1. Sieve tubes
2. Companion cells
3. Phloem parenchyma
4. Phloem fibres.

1. Sieve Tubes. These are long, slender, tube-like structures involved in the transport of solution of organic solutes like sucrose throughout the plants.

• These are formed by end-to-end fusion of cells called sieve tube elements or sieve elements. Rows of these cells develop in the apical meristem together with the primary xylem.
• The walls of sieve tube elements are made up of cellulose and pectic substances, as in parenchyma cells, but their nuclei degenerate and are lost as they mature. The cytoplasm is confined to a thin peripheral layer.
• Two adjoining end walls of neighbouring sieve elements form a sieve plate. Originally plasmodesmata passed through the walls, but later on, these pores enlarged, so that the walls looked like a sieve allowing the flow of solution from one element to the next.

2. Companion Cells. A thin-walled elongated cell called a companion cell is associated with each sieve tube. Both are connected by simple pits.

Each companion cell is living and contains dense protoplasm and a large elongated nucleus. The sieve tube elements do not have a nucleus, but they remain living, being dependent upon the adjacent companion cell.

3. Phloem Parenchyma. These are parenchymatous cells found in the phloem. These are living and often cylindrical. These are absent in most of the monocots. These mainly store food materials.

4. Phloem Fibres. Phloem fibres are similar to sclerenchyma fibres and provide mechanical support. Phloem fibres of plants like jute, flax and hemp are retted in water and extracted for making ropes and coarse textiles. Sclereids are more frequent in older phloems.

Secondary Growth In Flowering Plants Neet – NEET Questions Types of Vascular Bundles

• Vascular Bundle. A strand-like part of the plant vascular system (conducting system) containing xylem and phloem. the xylem and phloem may be separated by the fascicular
  cambium. the following types of vascular bundles are found in plants.

1. Conjoint Vascular Bundle. When phloem and xylem axes are present on the same radius, i.e. they are laterally placed to each other. It is of two types

1. Collateral and
2. Bicollateral.

• Collateral Vascular: If a strip of cambium is present between the phloem and xylem, they are called open bundles. If cambium is absent they are called closed bundles. If above the conjoint bundle, a sclerenchyma fibre is present the bundle is called fibrovascular bundle.
• Bicollateral Vascular Bundle. When in a collateral bundle, the problem is present both above and below the xylem bundles on the same radius. One group of phloem faces the pericycle and the other group faces the pith. This is seen in the Cucurbita stem and the cambium twice between both phloem groups lying above and below the xylem.

2. Radial Vascular Bundle. When the xylem and phloem lie on different radii alternating with each other, as in roots, the bundle is called radial.

Detailed Anatomy Of Flowering Plants For NEET Exam

3. Concentric Vascular Bundle. When the xylem is surrounded by phloem or vice versa, the vascular bundle is called concentric.

If the xylem is surrounded by phloem it is called a concentric amphicribal vascular bundle (Hydrocentric) i.e. Ferns (Lycopodium, Selaginella). But when a phloem is surrounded by a xylem, it is called a concentric amphivasal vascular bundle (Leptocentric) Example. Dragon plant (Dracaena) and Dagger plant (Yucca).

Anatomy Of Flowering Plants Chapter 6 Special Tissues

They are commonly secretory or excretory tissue For Example. laticiferous tissue and glandular tissue.

1. Laciceferous Or Laticiferous Tissues Or Laticifers

It is concerned with the secretion of latex or an emulsion or oils, alkaloids, resins, proteins and sugar. It consists of thin-walled, elongated branched ducts. The laticifers are of two types

• Latex vesseLs
• Latex celLs.

These occur irregularly distributed in the mass of parenchymatous cells.

• Latex Cells are called simple laticifers or non-articulated laticifers which may be unbranched or may be branched profusely but do not fuse to form a network quite common in the members of families Apocynaceae, Asclepiadaceae, Euphorbiaceae and Moraceae (For Example. milkweed. Euphorbia, Ficus etc.).
• Latex Vessels (Articulated laticifers) are formed by the union of latex cells (hence called compound Laticifers also) and are quite common in the family Papaveraceae (poppy family), Caricaceae (Papaya family), Compositae, Musaceae (banana family)

2. Glandular Tissue. They are isolated secretory structures which may be unicellular or multicellular. Example

1. Nectar-Secreting glands.
2. Nectar (or honey) is a sugary substance secreted by the nectar gland or nectaries which may be floral (present in flower) or extra floral (on vegetative parts).
3. Water-Secreting Structures (Water Stomata or Hydathodes) are present along the margins and apices of leaves. The exudation of water through these is called guttation.
4. Osmophores. They secrete essential oil.
5. Chalk Or Gland cells secrete salts For Example. Tamarix.

Simplified Notes On Anatomy Of Flowering Plants For Neet

Sachs (1975) distinguished three types of tissue systems in plants

1. Epidermal tissue system,
2. Ground tissue system,
3. Vascular tissue system.

1. Epidermal Tissue System

• It consists of the epidermis, the outermost layer of cells covering the entire surface of the plant body and epidermal outgrowths.
• The Epidermis of the stem, leaves and floral parts originate from the surface layer of the shoot apical cistern.
• In roots, the epidermis originates either from an independent Set of Initials or has a common origin with the root cap and cortex. It is called epithelia or piliferous layer, it may bear root hair.

In most of the angiosperms, it is single-layered (uniseriate), but in some (like leaves of Nerlum, Ficus, Olearulcr etc.) it is made up of two or more layers (multiseriate).

• Epidermal cells are living, thin-walled, with a large central vacuole and thin peripheral cytoplasm. These are compactly arranged without intercellular spaces. The basic function of the epidermis is to protect the plant from desiccation and infection.
• The epidermal cells secrete a waxy substance called cutin, which forms a layer of variable thickness (the cuticle) within and on the outer surface of its all walls. It helps in reducing the loss of water by evaporation and also checks the entry of pathogens.
• In Xerophytes, the cuticle is thick; in mesophytes, it is moderately thick; and is absent in hydrophytes. It is also absent in roots and underground parts.

Epidermal outgrowths are called trichomes (hairs or scales). The hair-like extensions may be unicellular or multicellular and serve a variety of functions.

In roots, Unicellular hairs are called root hairs, these absorb water and mineral salts. In stems, these are multicellular. Trichomes are epidermal outgrowths. Scales are flattened epidermal outgrowths.

Stomata occur in the epidermis of aerial parts. Depending upon the distribution of stomata, the leaves are

• Apple-Mulberry Type. Hypostomatic stomata only on the lower surface.
• Potato Type. Most common, amphistomatic but more on the lower surfaces,
• Oat Type. Amphistomatic, equal on two surfaces,
• Nymphaea Type. Epistomatic—only on the upper surface,
• Potamogeton Type. Astomatic or with nonfunctional stomata.

2. Ground Tissue System:

It comprises the internal structure of organs, excluding the circulatory system. The ground tissue system in leaves is referred to as mesophyll. It is categorized into hypodermis, cortex, endodermis, pericycle, pith, and medullary rays.

• The hypodermis imparts strength. The cortex is involved in food storage. In certain stems, the cells possess chloroplasts and are also photosynthetic.
• The cortex of immature roots transports absorbed water and minerals inward.
• The endodermis, the innermost layer of the cortex, contains Casparian strips in roots.
• In dicot stems, it is referred to as a starch sheath.
• The endodermis is lacking in the stems of monocots. The pericycle constitutes the external boundary of vascular tissues. It is unilayered in roots and multilayered in stems.

3. Vascular Tissue System:

It consists of a vascular strand or cylinder. The latter is made up of some vascular bundles. Vascular bundles are radial in roots and conjoint in other parts.

Anatomy Of Flowering Plants Chapter 6 Anatomy Of Root

Internal Structure of Dicot Root

A primary root arises from the radicle of the seed. It is generally cylindrical in outline and possesses the following structures, from outside towards the inside of the transverse section of the root:

1. Epiblema Or Piliferous Layer. It is the outermost layer which is made up of compactly arranged thin-walled parenchymatous cells. From epidermal cells, arise thin-walled tubular outgrowths called root hair. Due to the presence of root hair, the epiblema layer is also called as piliferous layer. The Epiblema layer is responsible for the absorption of water and minerals from the soil.
2. Cortex. Inner to epiblema is a multilayered cortex which is made up of thin walled cells. The cells of the cortex store food. These cells also conduct water from epiblema to internal tissue.
3. Endodermis. The innermost layer of the cortex is known as the endodermis. The endodermis consists of barrel-shaped cells with Casparian strips on their anti-clinal walls. Opposite to the protoxylem, the cells are thin-walled and called passage cells. Passage cells allow the free movement of water and minerals from the cortical cells in the xylem bundles.
4. Pericycle. Inner to endodermis is a layer of pericycle. From the pericycle arise lateral roots and also vascular cambium which brings about secondary growth in the root.
5. Vascular Bundle. Inner to pericycle are found 2-6 vascular bundles with alternating xylem and phloem. According to number, the root may be diarch, triarch, tetrarch and pentarch.

In the xylem, the protoxylem is outside and the metaxylem is towards the centre of the root. Such a xylem is called an exarch.

• Phloem is present in between two xylem bundles. Phloem consists of sieve tubes, companion cells and phloem parenchyma.
• Dicot root shows secondary growth. Cambium develops from pericycle and conjunctive parenchyma, and a ring of cambium is formed which cuts off the secondary xylem on the inner side and the secondary phloem on the outer side.

Anatomy Of Flowering Plants Chapter 6 Internal Structure of Monocotyledonous Root

The transverse section of the monocot root shows the following structures. There is no distinction between young and old monocot roots as there is no secondary growth in monocot rool The various layers of tissues are as follows:

1. Epiblema Or Piliferous Layer. It is the outermost layer which consists of thin-walled cells. Some cells produce root hair. It is meant for the absorption of water.
2. Cortex. Inner to epiblema is a multilayered cortex consisting of compactly arranged cells. It is meant for protection and storage of food.
3. Endodermis. It is single-layered and lies inner to cortex. The cells are barrel-shaped with Casparian strips on their radial walls. Opposite to protoxylem, endodermal cells are thin-walled and called passage cells.
4. Vascular Strand. It consists of several (8 or more) alternate radial xylem and phloem bundles. The vascular bundles are arranged in the form of a ring with a pith in the centre.
   • The xylem Is Exarch with a protoxylem towards the outside and a metaxylem towards the centre. Xylem elements are rounded. The xylem provides mechanical strength and is meant for the conduction of water and minerals.
   • The Phloem Alternates With The Xylem. The two are separated by conjunctive parenchyma. Phloem is meant for translocation of organic food.
5. Pith. Pith is present in the centre, consisting of parenchymatous cells. Pith stores food.

Anatomy Of Flowering Plants Chapter 6 Anatomy Of Stem

Structure Of Dicot Stem

A young dicot stem in the transverse section shows the following structures from the periphery towards the centre.

1. Epidermis
2. Cortex
3. Endodermis
4. Pericycle
5. Vascular bundles
6. Pith.

Structure Of Monocot Stem

In the monocot stem, there is no distinction between the cortex and the pith. There is ground tissue in which vascular bundles are scattered. The transverse section of Maize stems shows the following structures:

1. Epidermis
2. Ground tissue.
3. Vascular bundles.

Anatomy Of Flowering Plants Chapter 6 Anatomy Of Leaf

Internal Structure Of A Dicotyledonous Leaf Or Dorsiventral Leaf of Helianthus or Chenopodium can be studied under the following heads :

1. Epidermis. In the transverse section, there are upper epidermis and lower epidermis. The epidermis is single-layered. The cells of the epidermis are colourless and secrete a waxy layer of cuticle.

• In the epidermis are numerous minute apertures called stomata. Each stoma has two kidney-shaped guard cells. Stoma opens in the leaf in a sub-stomatal cavity.
• Besides guard cells, there are two specialised cells called subsidiary cells or accessory cells. The guard cells regulate the opening of a stoma.

Important Notes On Anatomy Of Flowering Plants For NEET

2. Mesophyll. In between the upper and lower epidermis, there is chloroplast containing photosynthetic tissue called mesophyll. Mesophyll is divided into two parts:

1. Palisade parenchyma
2. Spongy parenchyma.

• Palisade Parenchyma. It is present below the upper epidermis and consists of closely packed elongated cells. The cells contain abundant chloroplasts and are arranged in 2-3 layers.

The compactness of the cells of this layer reduces the transpiration. The main function of palisade tissue is to manufacture carbohydrates during photosynthesis.

• Spongy Parenchyma. It is present below palisade tissue and consists of loosely arranged irregularly shaped cells with large intercellular spaces in between them.

Spongy parenchyma is in contact with the atmosphere through stomata. Its function is transpiration and exchange of gases for respiration and photosynthesis. In addition, spongy parenchyma is photosynthetic in function.

3. Vascular System. There are many vascular bundles. Each vascular bundle is surrounded by a layer of parenchymatous cells called a bundle sheath. Each vascular bundle has a xylem towards the upper epidermis and a phloem towards the lower epidermis.

The xylem is meant for the conduction of water and minerals while the phloem is meant for the translocation of food. Cambium is absent in the leaf, so there is no secondary growth in the leaf.

Structure of A Monocotyledonous Leaf Or Isobilateral Leaf Grass Or Zea Mays.

The transverse section of a monocot leaf shows the following parts:

• Epidermis. It consists of a closely packed single layer of cells. Some cells in the epidermis are large, and thin and contain water and are called bulliform cells. In epidermis are present stomata. Each stoma has two dumbbell-shaped guard cells.
• Mesophyll. There is no distinction between palisade and spongy parenchyma. The mesophyll consists of similar types of cells rich in chloroplast. There is no distinction between palisade and, spongy parenchyma. The main function of mesophyll is photosynthesis.
• Vascular System. The vascular bundles are present in a row. Each vascular bundle is surrounded by a sclerenchymatous bundle sheath. In the vascular bundle xylem is towards the upper epidermis and the phloem towards the lower epidermis. There is no cambium. So vascular bundle is closed.

Secondary Growth

Secondary Growth is growth brought about by secondary meristem. It may be classified into two types:

Normal And Anomalous. Growth brought about by fascicular cambium is called normal. Secondary growth of vasculature brought about by extra fascicular cambium (arising either in the pith or cortex) is called anomalous.

• In dicots, secondary growth is seen in the vascular cylinder as well as in the cortex. Vascular cambium produces secondary vascular tissue while cork cambium produces periderm tissue.
• In monocots vascular bundles are closed, thus there is no secondary growth. In some monocots, Dracaena, Yucca, Aloe, Agava, and Sanserveria, secondary growth occurs.

Anatomy Of Flowering Plants Chapter 6 Steps Of Secondary Growth

• Secondary growth results from the activities of the cambium and cork cambium.
  The cambium is a lateral meristem that is one cell thick radially.
• It consists of fusiform initials and ray initials. It may be multi-storeyed or single-storeyed.
• A cambium ring consisting of intra- and interfascicular cambial strips is established.
• It generates secondary xylem internally and secondary phloem externally. Additionally, secondary medullary rays are produced on both sides.
• The secondary xylem and phloem form a vertical and a horizontal system. The latter in both instances consists of ray parenchyma.
• The secondary medullary rays consist of upright and reclining cells. The rays might be either homocellular or heterocellular. They can be homogeneous or heterogeneous, and uniserate, biserate, or multiserate.
• The growth throughout the spring and fall seasons results in spring and autumn woodlands, respectively. The two types of wood form the annual ring. The age of the plant can be approximated by counting the annual rings.
• The wood can be either porous or non-porous, with the porous category further classified as ring porous or diffuse porous.
• The paratracheal parenchyma generates balloon-like formations known as tyloses within the tracheary components.

The wood is thereafter categorized into a narrow, light-hued region known as sapwood or alburnum, and a dark-hued, large region referred to as heartwood or duramen.

• The sapwood is physiologically active, facilitating the ascent of sap. The heartwood has more resistance than sapwood. Reaction wood develops as a response to stress. It could be either tension wood or compression wood.
• The extra-stellar zone expands when a cork cambium (phellogen) develops in the cortex or epidermis.
• The phellogen generates cells outside that undergo suberization to produce cork (phellem). The cells on the inner side remain thin-walled and constitute the secondary cortex (phelloderm).
• The three layers, namely phellem, phellogen, and phelloderm, collectively form the periderm. Non-suberized cells of phellem are referred to as spheroids.
• All tissue external to the vascular cambium is referred to as bark. The tissue external to the innermost phellogen forms the outer bark or rhytidome, while the remaining tissue is classified as the inner bark.
• The bark can be scaly, papery, ring-shaped, or exhibit intermediate characteristics.
• Commercial cork is derived from Quercus suber. The initial layer is referred to as a virgin cork. It is lightweight, robust, flexible, a poor conductor of heat and electricity, and impermeable to liquids and gasses.
• A wound, once created, is promptly filled with cork cells known as wound cork, produced by the activity of phellogen.
• A lenticel develops at the stomatal site. The sub-lenticular cells serve as the complimentary cells. A phellogen is established, generating new complimentary cells and protective layers.
• When branches accelerate in the stem as a result of secondary growth, nodes are generated.

Anatomy Of Flowering Plants Chapter 6

Plant tissue may be classified into two main groups i.e. meristematic tissue and permanent tissues.

1. According to position, the meristem is of three types i.e. apical, intercalary and lateral.
2. The apical meristem lies at the apex of both stem and root.
3. Various types of trichomes are
   • Simple
   • Unicellular,
   • Multicellular
   • Multicellular with protuberance and
   • Multicellular
   • Branched and
   • Stinging and
   • Glandular
4. In a dicot root, there are 2 to 6 xylem bundles while in monocots there are more than six.
5. Latex of Carica papaya (papaya) contains papain. Latex of poppy yields opium which contains the alkaloid morphine.
6. Latex of Bananas contains tannin.
7. Though Hevea brasiliensis (Para rubber) and Manihot glaziovi belong to the family Euphorbiaceae, these contain latex vessels (not latex cells).
8. Latex cells are found in Cannabis, Vinca minor and Urtica dioica. Para rubber and Indian rubber are obtained from the latex of Hevea brasiliensis and Ficus elasticatively.
9. Aristolochia And Bougainvillea show anomalous secondary growth.
10. The periderm is a secondary protective tissue that replaces the epidermis during secondary growth. It consists of phellogen (cork cambium) which produces phellem towards the outside and phelloderm towards the inside.
11. Endodermoid. The term is used by some authors for endodermis or starch sheath of young stems because of the absence of Casparian strips.
12. Leaf Primordium. Develops from a lateral protrusion or leaf buttress. It grows initially by an apical meristem (permanent in ferns) and then by intercalary meristem.
13. The leaf consists of only primary tissues. Secondary growth is limited to wound healing.
14. The epidermis which covers the upper surface of the leaf is called the adaxial epidermis while that which covers the lower surface is known as the abaxial epidermis.
15. In grasses and Equisetum, silica is present in the epidermal cells.
16. Epidermal cells containing cystoliths are called lithocysts.
17. The epidermis of garlic (Allium sativum), scales and seeds of peas and beans are made up of sclereids.
18. Usually, epidermal cells are colourless, but hydrophytes and sciophytes, contain chloroplasts and are hence, green.
19. Cork is light, highly compressible and does not catch fire.
20. In the deserts; 60 cm. high plant Aerva persica plant can have a tap root system reaching a depth of 6 metres.
21. Apoplast. The non-living parts (For Example. xylem, cellulose, intercellular space, etc.) of the plant are called apoplast.
22. Symplast. Living parts (cytoplasm-containing cells) of the plant.
23. Sclerenchymatous patches of the pericycle outside the vascular bundles are called bundle caps.
24. Lateral roots arise endogenously from the pericycle cells.
25. Medullary vascular bundles are found in the stems of Mirabilis, Boerhaavia, Amaranthus, etc. The plants show anomalous secondary growth.
26. Abscission. It involves the formation of a special parenchymatous layer called abscission or separation layer at the base of the organ and a layer of suberised thick-walled ‘cork’ cells called a protective layer over the mother axis. Degeneration of cells of abscission or separation layer causes abscission.

Anatomy Of Flowering Plants Chapter 6

Vessels are an advanced type of conducting element and are characteristically found in angiosperms. Some primitive vessel-less angiosperms belong to the families—Winteracae, Trochodendraceae and Telracentraceae. Some pteridophytes (Selaginella, Pteridium) and gymnosperms (Gnetum) have got vessels.

1. Wood without vessels is homozygous while the one with vessels is heterozygous.
2. Gymnosperms With Vessels. Members of group gnetales.
3. Pteridophytes With Vessels. Occasional in species of Selaginella, Dryopteris, Marsilea, etc.

Fibres present outside the xylem are called extrasolar fibres. They may be cortical, pericyclic (or perivascular) or phloem (bast) fibres.

1. Except xylem parenchyma, the xylem is a dead tissue.
2. Sieve tubes were first discovered by Hartig (1837).
3. In phloem, companion cells and sieve tubes arise from the same mother cell.
4. Slime plugs are dense funnel-shaped structures formed by the coagulation of slime bodies on sieve plates.
5. conifers (gymnosperms), albuminous cells are found-analogous to companion cells.

Since companion cells and sieve tubes arise from the same mother cell, these are called sister cells.

1. Knot. As the stem grows in thickness, the bases of branches become embedded in the secondary xylem and thus knots are formed. The buried portion can neither grow in diameter nor can be pushed outward.
2. When a log is cut vertically, the branch embedded in it as a knot, is cut transversely.
3. P-proteins are proteinaceous structures present in sieve tubes and are believed to be responsible for
4. Movement of materials through the cell,
5. Sealing of pores after wounding.
6. Bhojpatra is derived from the bark of Betula utilis.

The waxy substance associated with the walls of cork cells is suberin and the phenomenon of impregnation of cell walls with suberin is called suberisation.

1. Cutin forms a continuous layer on the epidermis, which is known as a cuticle.
2. The formation of the cuticle is called cuticularization.
3. Apical cell theory was proposed by Hofnieister (1857) and supported by Nageli.
4. Histogen theory was given by Hanstein (1868) and supported by Strassburger.
5. Heartwood. Most abundant in Mulberry but absent in Poplar and Willow.
6. There is no distinction between heart wood and sap wood in Salix, Populus, etc.
7. In Morus, Taxus, the heartwood is most abundant and the sapwood zone is quite thin.

Heartwood is dark-coloured due to the deposition of extractives and is considered durable.

1. Heartwood is the dead primary or old xylem. Most Durable Soft Wood. Cedras deodara.
2. Most Durable Wood. Teak (Tectona grandis).
3. Lightest Wood. Ochroma pyramidale ( = 0. lagopus).
4. Heaviest Wood. Guaiacwn officinale. In India Acasia sundra.
5. The bark of Cinnamomum leylanicum (Dalchini) is used as a flavouring material.
6. In Angiosperms vessels are present along with tracheids.
7. In the sieve tube nucleus is absent.

Anatomy Of Flowering Plants NEET Previous Year Questions

Companion cells occur only in Angiosperms and are absent in Pteridophytes and Gymnosperms.

1. Phloem parenchyma is absent in monocots.
2. Xylem cells are polygonal in dicots and oval in monocots.
3. Normally no secondary growth in monocot stems except anomalous secondary growth in Dracaena, Yucca etc.
4. In monocots, grafting is not successful due to closed and scattered vascular bundles.
5. In a hollow-hearted plant, the growth of the plant is not affected.
6. Wound healing and secondary growth are controlled by secondary meristems.

Swollen exogenous protuberances on the growing apices are leaf primordia.

1. Sieve elements are living enucleated structures.
2. Tissue builder zones are three in the shoot apex and four in the root apex.
3. Raphides are the crystals of calcium oxalate.
4. Amphivasal is where the xylem surrounds the phloem.
5. Clayptrogen histogen forms a root cap.

Climatic variations are almost zero in seashore plants therefore cambium has uniform activity without demarcation of annual rings.

1. The leaf consists of only primary tissues. Secondary growth is limited to wound healing.
2. Leaf primordium develops from a lateral protrusion or leaf buttress. It grows initially as apical meristem (permanent in ferns) and then by intercalary meristem.
3. The epidermis which covers the upper side of the leaf is called the adaxial epidermis.
4. The epidermis which covers the lower surface is called the abaxial epidermis.
5. Cells of bark i.e. cork of phellem cells are made up of impervious suberin.
6. After the formation of phellem, the stomata are obliterated and new proes are formed which are lens-shaped hence lenticels.

NEET Biology Plant Anatomy Multiple Choice Questions And Answers

Question 1. Meristematic cells have:

1. Large prominent nucleus and dense cytoplasm
2. No intercellular spaces
3. Rounded shape
4. All the above.

Answer: 4. All the above.

Question 2. The cells or tissues of plants which have lost the power of division are called:

1. Meristematic
2. Permanent
3. Protoderm
4. Promeristem.

Answer: 2. Permanent

Question 3. Promeristems can be distinguished from primary meristems by:

1. Their apical position
2. By their power of active division
3. The presence of a large prominent nucleus
4. All the above.

Answer: 4. All the above.

Question 4. The undifferentiated cells are present in:

1. Maple tree root system
2. Sepals of geranium flower
3. Cambium of oak
4. Root of Raphanus.

Answer: 3. Cambium of oak

Read and Learn More NEET Biology Multiple Choice Question and Answers

Important MCQs On Plant Anatomy Question 5. The tip of the root apical meristem is capped by the histogen, known as:

1. Dermatogen
2. Periblem
3. Calyptrogen
4. Plerome.

Answer: 3. Calyptrogen

Question 6. Meristematic cells are:

1. Thin-walled, isodiametric, nucleate and less protoplasmic
2. Thin-walled, isodiametric, nucleate and densely protoplasmic
3. Thick-walled, isodiametric, non-nucleate and densely protoplasmic
4. Thick-walled, isodiametric, nucleate and less protoplasmic.

Answer: 2. Thin-walled, isodiametric, nucleate and densely protoplasmic

Question 7. The root apical meristem is subterminal because it:

1. Is covered by root hairs
2. Is covered by the root cap
3. Has many corpus cells
4. Is covered by tunica cells.

Answer: 2. Is covered by the root cap

Question 8. Cork cambium is a:

1. Promeristem
2. Lateral meristem
3. Intercalary meristem
4. Ground meristem.

Answer: 2. Lateral meristem

Question 9. Primary vascular tissues are derived from:

1. Protoderm
2. Procambium
3. Ground meristem
4. Calyptrogen.

Answer: 2. Procambium

Anatomy of Flowering Plants NEET Questions Question 10. The epidermis in the stem is produced from:

1. Protoderm
2. Procambium
3. Ground meristem
4. Calyptrogen.

Answer: 1. Protoderm

Question 11. The pith in the stem is derived from:

1. Protoderm
2. Procambium
3. Ground meristem
4. Plate meristem.

Answer: 3. Ground meristem

Question 12. Epiblema in roots is derived from :

1. Protoderm
2. Procambium
3. Ground meristem
4. Calyptrogen.

Answer: 1. Protoderm

Question 13. The histogen concept was proposed by:

1. Schmidt
2. Nageii
3. Hanstein
4. Strassburger

Answer: 3. Hanstein

Question 14. The lateral meristem is responsible for:

1. Increasing height
2. Increasing thickness
3. Increasing tissue
4. None of the above.

Answer: 2. Increasing thickness

Question 15. The tissue is made up of thin-walled rectangular cells responsible for the secondary growth:

1. Cortex
2. Xylem
3. Cambium
4. Pith.

Answer: 3. Cambium

Anatomy of Flowering Plants NEET Questions Question 16. Root cap in dicots is formed from:

1. Ground meristem
2. Procambium
3. Protoderm
4. Calyptrogen.

Answer: 4. Calyptrogen.

Question 17. Intercalary meristems are derived from:

1. Permanent tissue
2. Secondary meristem
3. Lateral meristem
4. Apical meristem.

Answer: 4. Apical meristem.

Plant Anatomy MCQs Question 18. Secondary meristems are derived from:

1. Apical meristem
2. Intercalary meristem
3. Lateral meristem
4. Permanent tissues.

Answer: 4. Permanent tissues.

Question 19. The vascular cambium of the root is an example of meristem:

1. Apical meristem
2. Intercalary meristem
3. Secondary meristem
4. Root apical meristem.

Answer: 3. Secondary meristem

Question 20. Tunica corpus theory was proposed by:

1. Hanstein
2. Schmidt
3. Nageli
4. Hofmeister.

Answer: 2. Schmidt

Important MCQs on Anatomy of Flowering Plants Question 21. Dermatogen is tissue formed by apical meristem and it develops into:

1. Pith
2. Vascular bundles
3. Epidermis
4. Cortex.

Answer: 3. Epidermis

Question 22. Grass stem elongates by the activity of:

1. Cambium
2. Intercalary meristem
3. Apical meristem
4. Primary meristem.

Answer: 2. Intercalary meristem

Question 23. The concept envisaging three distinct zones of cells of new tissue builders at the stem and root apices is known as:

1. Meristem theory
2. Histogen theory
3. Dermatogen theory
4. Tunica colpus theory.

Answer: 2. Histogen theory

Question 24. Which of the following clogs the cavity of the xylem vessels?

1. Tyloses
2. Cystoliths
3. Hydathode
4. Raphides.

Answer: 1. Tyloses

Important MCQs on Anatomy of Flowering Plants Question 25. Carnbium which produces cork is known as:

1. Phelloderm
2. Phellogen
3. Phellern
4. Periblem.

Answer: 3. Phellern

Question 26. When we peel the skin of a potato tuber, we remove:

1. Epidermis
2. Periderm
3. Cuticle
4. Sapwood

Answer: 2. Periderm

Question 27. In which meristem do you see cell divisions occurring in all planes?

1. Lile meristem
2. Plate meristem
3. Lateral meristem
4. Ground meristem.

Answer: 4. Ground meristem.

Question 28. Which is the first wall layer formed by dividing plant cells and occurring between subsequently formed cell walls of daughter cells?

1. Primary wall
2. Secondary wall
3. Middle lamella
4. Cellulose layer.

Answer: 3. Middie lamella

Important MCQs on Anatomy of Flowering Plants Question 29. The fascicular cambium in a dicotyledonous stem is a meristematic tissue referred to as :

1. Apical
2. Lateral
3. Primary
4. Intercalary.

Answer: 2. Lateral

Question 30. Which new tissues of the plant body originate in the apical meristems?

1. Parenchyma
2. Collenchyma
3. Sclerenchyma
4. Secondary.

Answer: 1. Parenchyma

Question 31. Intercalary meristems are present in the following:

1. Nodai region
2. Internodal region
3. Bryophytes
4. The nodal region is close to the base of the plant.

Answer: 1. Nodai region

Question 32. The basic differences between a vessel and a tracheid are:

1. Types of pits
2. Size and types of pits
3. Perforations on end walls
4. Length wall thickness and lignification.

Answer: 3. Perforations on end walls

Important MCQs on Anatomy of Flowering Plants Question 33. Which is not true about the sclereids?

1. These are parenchymatous cells with thick lignified cell wall
2. They are elongated and flexible and their ends are tapering
3. Generally, they are found in the rind of drupe fruits and pulp of guava and pear
4. They are also called stone cells.

Answer: 2. They are elongated and flexible and their ends are tapering

Question 34. Primary growth of a tree:

1. Occurs through the activities of apical meristems
2. Occurs through the activity of a vascular cambium
3. Occurs through the activity of the root cap
4. Occurs only in the first year of the tree’s life.

Answer: 1. Occurs through the activities of apical meristems

Question 35. Secondary xylem and phioem are laid down by:

1. Apical meristems
2. Axillary meristems
3. Vascular cambium
4. Cork cambium.

Answer: 3. Vascular cambium

Question 36. Which of the following would not secrete a cuticle?

1. Leaf epidermis
2. Stem epidermis
3. Root epidermis
4. Xerophytes.

Answer: 3. Root epidermis

Question 37. One year’s growth in length of a young woody shoot is the distance between successive:

1. Rings of bud scale scars
2. Leal scars
3. Branches
4. Axillary buds.

Answer: 1. Leal scars

Question 38. Anatomically jute fibres are:

1. Vertical fibres
2. Pith fibres
3. Xylem fibres
4. Phloem fibres.

Answer: 4. Phloem fibres.

Question 39. Xylem that is not conducting water is called:

1. Heartwood
2. Sapwood
3. Springwood
4. Summerwood.

Answer: 1. Heartwood

Important MCQs On Plant Anatomy Question 40. Intercalary meristem is seen in:

1. Maize
2. Ficus
3. Cabbage
4. Cucurbita.

Answer: 1. Maize

Question 41. Tunica and corpus organization occurs in:

1. Lateral meristem
2. Root apex
3. Shoot apex
4. Intercalary meristem.

Answer: 3. Shoot apex

Question 42. Tree trunk increases in girth because of the cell division activity in:

1. Epidermal tissues
2. Supporting tissues
3. Meristematic tissues
4. None of the above.

Answer: 3. Meristematic tissues

Question 43. In the root, the maximum growth occurs:

1. In the presence of high-temperature
2. In the presence of light
3. At the apex
4. Behind the apex.

Answer: 4. Behind the apex.

Question 44. Chlorenchyma cells are:

1. Chlorophyll-containing sclerenchyma cells
2. Chlorophyll-containing epidermis
3. Chlorophyll-containing parenchyma
4. Chlorophyll-containing phloem.

Answer: 3. Chlorophyll-containing parenchyma

Plant Anatomy MCQs Question 45. Sclerenchyma cells are mostly:

1. Living cells
2. Dead cells
3. Pat of xylem vessels
4. Part of pericycle.

Answer: 2. Dead cells

Question 46. Abnormal secondary growth due to accessory cambia is found in:

1. Helianthus
2. Cucurbita
3. Dracaena
4. Maize.

Answer: 3. Dracaena

Question 47. Secondary meristems are set apart from primary meristems in that they:

1. Are responsible for secondary growth
2. Increase the size of the state
3. From the cork and secondary vascular tissue
4. Always arise in permanent tissue.

Answer: 4. Always arise in permanent tissue.

Question 48. In amphiphilic siphonostele, phloem is:

1. Internal to xylem
2. External to xylem
3. Surrounded by xylem
4. On both sides of the xylem.

Answer: 4. On both sides of the xylem.

Plant Anatomy MCQs Question 49. The science of dendrochronology is applied to determine:

1. The age of trees
2. Date of archaeological objects
3. Ecological succession of trees
4. Tree-like concept of evolution.

Answer: 1. The age of trees

Question 50. Cork of commercial value is obtained from:

1. Quercus
2. Mango
3. Pines
4. Cedrus deodara.

Answer: 1. Quercus

Question 51. The first event during the secondary growth of dicot root is the division of:

1. Cambial initial between xylem and phloem
2. Pericyclic cells external to primary xylem
3. Conjunctive cells form circular cambium
4. Parenchyma cells are internal to the primary phloem.

Answer: 3. Conjunctive cells to form circular cambium

Question 52. Collenchyma mainly forms:

1. Hypodermis
2. Epidermis
3. Phloem
4. Inner cortex.

Answer: 1. Hypodermis

Question 53. Xylem and phloem in plants are concerned with conduction like arteries and veins. Yet unlike the arteries and veins, together they cannot be termed a circulatory system because:

1. No liquid moves through these elements
2. Gases are not transported by these tissues
3. Plants lack the heart to pump
4. Movement is not in a circular manner from one to the other.

Answer: 4. Movement is not in a circular manner from one to the other.

Question 54. Xylem parenchyma occurring in association with vessels is known as:

1. Paratracheal xylem parenchyma
2. Apotracheal xylem parenchyma
3. Syntracheal xylem parenchyma
4. Associated xylem parenchyma.

Answer: 1. Paratracheal xylem parenchyma

Plant Anatomy MCQs Question 55. Angular collenchyma is found in:

1. Althea
2. Cucurbita
3. Lactuca
4. Salvia.

Answer: 2. Cucurbita

Question 56. Youngest layer of secondary xylem is adjacent to:

1. Cortex
2. Pith
3. Cambium
4. Pericycle.

Answer: 3. Cambium

Question 57. External protective tissue of plants are:

1. Pericycle and cortex
2. Epidermis and cork
3. Cork and pericycle
4. Cortex and epidermis.

Answer: 2. Epidermis and cork

Question 58. Angiosperms have:

1. Tracheids only
2. Vessels absent
3. Vessels present
4. Sieve tubes are absent.

Answer: 3. Vessels present

Question 59. Fusiform initials form:

1. Tracheary elements
2. Phloem parenchyma
3. Vascular rays
4. Ray parenchyma.

Answer: 1. Tracheary elements

Question 60. Which of the following lies in between the bark and wood of a tree trunk?

1. Cork cambium
2. Phloem
3. Vascular cambium
4. Primary cortex.

Answer: 3. Vascular cambium

Question 61. Plant fibres can originate from:

1. Phloem, xylem, epidermis and sclerenchyma tissues
2. Xylem, epidermis and sclerenchyma tissues
3. Phloem, xylem and sclerenchyma tissues
4. Xylem, phloem and epidermis tissues.

Answer: 1. Phloem, xylem, epidermis and sclerenchyma tissues

Question 62. Sieve tubes are best suited for translocation because they:

1. Possess no end wall
2. Are broader than long
3. Possess a broad lumen and perforated wall end
4. Possess bordered pits.

Answer: 3. Possess a broad lumen and perforated wall end

Important MCQs on Anatomy of Flowering Plants Question 63. Promeristem is found in:

1. Embryo
2. Root apex
3. Shoot apex
4. All of the above.

Answer: 1. Embryo

Question 64. Which of the following do not have a nucleus but are still living?

1. Sieve tubes
2. Trachea.
3. Companion cell
4. Phloem fibres.

Answer: 1. Sieve tubes

Question 65. Abundant root hairs are present in:

1. Eichhornia
2. Hydrilla
3. Commelina
4. Pistia.

Answer: 1. Eichhornia

Question 66. The cell layer located at the periphery in the cross-section of the root is called:

1. Endodermis
2. Epiblema
3. Pericycle
4. Xylem.

Answer: 2. Epiblema

Question 67. Lateral roots arise from the:

1. Endodermis
2. Epidermis
3. Pericycle
4. Pith.

Answer: 3. Pericycle

Question 68. The endodermis is the innermost layer of the:

1. Xylem
2. Phloem
3. Cortex
4. Cambium.

Answer: 3. Cortex

Question 69. Casparian strips occur in:

1. Endodermis
2. Epidermis
3. Pericycle
4. Cortex.

Answer: 1. Endodermis

Question 70. Radial vascular bundles occur in:

1. Stems
2. Dicot stem
3. Monocot stem
4. Monocot root.

Answer: 4. Monocot root.

Important MCQs on Anatomy of Flowering Plants Question 71. Well-developed pith is found in:

1. Monocot root and monocot stem
2. Monocot root and dicot stem
3. Monocot stem and dicot root
4. Dicot root and dicot stem.

Answer: 2. Monocot root and dicot stem

Question 72. Protoxylem lacunae are characteristic features of:

1. Climbers
2. Underground stem
3. Vascular bundles of the stem of grasses
4. Cladode.

Answer: 3. Vascular bundles of the stem of grasses

Question 73. The centrifugal arrangement of the xylem is called:

1. Monarch
2. Diarch
3. Polyarch
4. Exarch.

Answer: 4. Exarch.

Question 74. The xylem in the monocot root is:

1. Monarch
2. Diarch
3. Triarch
4. Polyarch.

Answer: 4. Polyarch.

Question 75. Cortex in the monocot root constitutes:

1. Parenchymatous cells
2. Collenchymatous cells
3. Sclerenchymatous cells
4. Companion cells.

Answer: 1. Parenchymatous cells

Question 76. Root hairs are:

1. Acellular
2. Unicellular
3. Multicellular
4. Multicellular and unicellular.

Answer: 2. Unicellular

Question 77. Monocot root differs from dicot root in having:

1. Scattered vascular bundles
2. Well developed pith
3. Endarch vascular bundles
4. Open vascular bundles.

Answer: 2. Well-developed pith

Question 78. The main function of xylem is:

1. Protection
2. Storage of food
3. Conduction of water and minerals
4. None of the above.

Answer: 3. Conduction of water and minerals

Question 79. Vascular cambium in dicot root develops from:

1. Endodermis
2. Pericycle
3. Conjunctive parenchyma
4. Both (2) and (3).

Answer: 4. Both (2) and (3).

Important MCQs on Anatomy of Flowering Plants Question 80. Vessels are characteristic of:

1. Angiosperms only
2. Gymnosperms only
3. Pteridophytes only
4. None of the above.

Answer: 1. Angiosperms only

Question 81. Root hair arises from:

1. Pericycle
2. Endodermis
3. Cortex
4. Epiblema.

Answer: 4. Epiblema.

Question 82. Tyloses are found in:

1. Secondary xylem
2. Secondary phloem
3. Callus tissue
4. Cork cells.

Answer: 1. Secondary xylem

Question 83. After secondary growth, the copies in the dicot root:

1. Remains intact
2. Is completely sloughed away
3. Is largely lost
4. Is converted to cork.

Answer: 3. Is largely lost

Question 84. Monocot root differs from dicot root in:

1. Showing no secondary growth
2. No hairs
3. No cambium
4. All the above.

Answer: 3. No cambium

Question 85. Exarch xylem is found in:

1. Root
2. Stem
3. Leal
4. Rachis.

Answer: 1. Root

Plant Anatomy MCQs Question 86. Stem and flrots olqucifeme grow due to actiraty of:

1. Cortex
2. Cambium
3. Phloem
4. Endoderm.

Answer: 2. Cambium

Question 87. Pith is absent or reduced in:

1. Dicot root
2. Dicot stem
3. Monocot stem
4. Monocot root.

Answer: 1. Dicot root

Question 88. Two to five xylem bundles are found in:

1. Monocot root
2. Monocot stem
3. Dicot stem
4. Dicot root.

Answer: 4. Dicot root.

Question 89. Maximum amount of growth in roots occurs due to :

1. Auxins
2. Root cap region
3. Presence of light
4. Darkness.

Answer: 1. Auxins

Question 90. The tip of the root apical meristem is covered by a root pocket in:

1. Brassica
2. Eichhornia
3. Petunia
4. Wheat.

Answer: 2. Eichhornia

Question 91. Raphides are:

1. Starch
2. Silica
3. Calcium carbonates
4. Calcium oxalate.

Answer: 4. Calcium oxalate.

Question 92. Raphides are found in:

1. Citrus
2. Colocasia or monocots
3. Nerium
4. Mango.

Answer: 2. Colocasia or monocots

Plant Anatomy MCQs Question 93. If the heartwood region of the plant is removed or decays:

1. The root will die first
2. Shoot will die first
3. Root and shoot die together
4. Neither root nor shoot till die.

Answer: 4. Neither root nor shoot till die.

Question 94. In the dicot stem the vascular bundles are:

1. Not found at all
2. Closed and show sclerenchymatous bundle sheath
3. Arranged in a ring
4. Are scattered in the ground tissue.

Answer: 3. Arranged in a ring

Question 95. In a dicot stem, the vascular bundle is:

1. Concentric
2. Collateral
3. Excentric
4. Radial.

Answer: 2. Collateral

Question 96. The most common type of ground tissue is:

1. Epidermis
2. Collenchyma
3. Parenchyma
4. Sclerenchyma.

Answer: 3. Parenchyma

Question 97. Mark the openings on a tree trunk for respiration:

1. Stomata
2. Hydathode
3. Lenticels
4. Cracks.

Answer: 3. Lenticels

Question 98. In monocots vascular bundles are:

1. Open
2. Closed
3. Bicollateral
4. Radial.

Answer: 2. Closed

Plant Anatomy MCQs Question 99. Growth rings determine:

1. Age
2. Length
3. Breadth
4. Number of branches of a plant.

Answer: 1. Age

Question 100. Vascular bundles are arranged in a ring in:

1. Dicot stem
2. Dicot root
3. Monocot stem
4. Monocot leaf.

Answer: 1. Dicot stem

Animal Kingdom Non-Chordate Phyla Classification Of Animal Kingdom

There are about 1.2 million animal species which show a great diversity of life. Though the animals are metazoans like the plants they differ from plants in several characteristics like the absence of plastids, cell wall, and central vacuole; and having centrosomes in the cells.

These are exclusively heterotrophic and are mostly holozoic in their nutrition. These also pass through certain larval stages during their development.

Classification Of Animal Kingdom For NEET Criteria Of Classification

Habitat Mode of living and orientation of the body

• Aquatic. Those animals which live in water.
• Marine. Those animals which live in seawater.
• Freshwater. Those live in waters other than sea water Exampleponds, drains, ditches, lakes, rivers, slow or fast running streams, etc.
• Amphibious. Those animals which can live on land as well as in water, Examplefrog.
• Terrestrial. Those that live on land Exampleman, lizards, etc.
• Aerial. Those animals which can live in the air, Examplebirds and bats.
• Zooplanktons. These float on the water’s surface and are drifted by water currents Example small crustaceans like Daphnia, Cyclops, etc.
• Nektons. These swim actively in a sea or a lake Examplemost of fishes. Zooplanktons and the nektons which live in open waters, are collectively called pelagic animals.
• Benthos. These live on the bottom of water bodies Examples, are corals, echinoderms, etc.
• Out of these, sponges and corals are fixed to the substratum and are called sedentary or sessile animals.
• Neustons are animals floating or swimming in surface waters. Neritic are the animals found in coastal waters.
• Terrestrial animals. These animals live on land. They are again of the following types:
• Scansorial animals. These climb the walls, rocks, etc. Examples are lizards, flying squirrels, etc.
• Aerial animals. These can go in the air Examplemost for insects and birds, bats, etc.
• Cursorial animals. These are fast-runners Examplehorse, rabbits, lions etc.
• Pelagic. Living in the surface water of the sea.
• Arboreal. Those animals which live on trees and catch hold of tree branches Examplemonkeys.
• Burrowing (Fossorial). Those animals that form burrows in the sand or soil, for example – earthworms, snakes, some fishes, etc.
• Cave dwelling. Those which live in caves, for example- Lions and some fishes.
• Solitary. Those animals that live alone or single individually Exampleman, cats, dogs, etc.
• Colonial. Those which form colonies to live together, for example- Bees, ants, some coelenterates, (Physalia, Obelia), porifers (Sycon), etc Sedentary. These are fixed animals attached to substratum Example sponges, obelia, and
  most coelenterates.
• Free swimming. They swim actively in water. Sessile. These animals do not possess stalk. Sub-sessile. They possess stalk.
• Orientation of body
• Oval shaped. The shape of the body is like an egg.
• Cylindrical. The shape of the body is long and spherical, resembling a cylinder.
• Elongated. The body is long.
• Oblong. The body is oval and long (oval + long)
• Depressed body Dorsoventrally flattened body.
• Laterally compressed. Pressed laterally.
• Abond. Located away from, or on the opposite side of the mouth.
• Adoral. Located on the same side of the body surface as the mouth.

Body Segmentation

• Metamerically segmented body. A linear repetition of body parts is known as a segmentation (metamerism) example. Pheretima.
• Somite. Each repeated unit is somite.
• Appendages. Body pints protrude from the main body and serve in locomotion, feeding, mating, etc.

Skeleton

• Exoskeleton. Skeleton, which lies outside the body, for example- scales, feathers, nails, hairs, etc. It protects the body.
• Endoskeleton. Skeleton which lies inside the body, supports and protects internal organs, composed of cartilage or bone.

Detailed Notes On Non-Chordates Classification For NEET

Formation of mouth

• Protostonies. In most of the phyla (Platyhelmithes, Annelida. Arthropoda, Mollusca, and smaller groups), a tired mouth is formed in front of the blastopore of the embryo. These are called protostomes.
• Deuterostomes. In echinoderms, hemichordates, and chordates, the mouth arises remote front of the blastopore, and the latter becomes the anus.

Mode of running

Unguligrade

• Running on the tips of digits Example Horse, Rhinoceros, Ass, Zebra, Giraffe, etc.
• Plantigrade Walking on the palm of sole
• Digitigrade—Walking on toes Example Cat, Dog.

Level of organization

• Cellular organization. The animal body is formed of many cells but the cells show no coordination to form tissues Example sponges.
• Tissue organization. The animal body is formed of many cells that coordinate for the specific function and form four types of tissues Example epithelial tissue, connective tissue, muscular tissue, and nervous tissue Example coelenterates like Hydra.
• Organ-system organisation. The body is multicellular and cells coordinate to form tissues, organs, and systems Examples from flatworms to mammals.

Symmetry

Asymmetry- When the animal cannot be cut into two halves Example Amoeba. Radial or Biradial Symmetry. The radially symmetrical animals are mostly spherical or cylindrical. These can be cut into two halves, if we cut them through any radius of the animal, for example, most of the coelenterates and all the echinoderms.

Radial symmetry is again of the following types:

1. Tetramerous Radial symmetry. When in radial symmetry, the body parts are arranged in fours or multiples of four Example Jellyfish.
2. Pentamerous Radial symmetry. When in radial symmetry, the body parts are arranged in five or multiples of five Example echinoderms.
3. Hexamerous Radial symmetry. When in radial symmetry, the body parts are arranged in sixes or multiples of six Example Sea anemone. In sea anemones, the body can be divided into two similar parts only by one or two vertical planes and have biradial symmetry.
4. Bilateral symmetry. When the animal can be cut into two exactly equal and similar halves by one plane only Example Platyhelminthes to Chaetognatha and also vertebrates.

Sides in a Bilaterally Symmetrical Animal.

• Anterior side. It is that side of the body which is kept forward during locomotion.
• Posterior side. It is that side of the body that is opposite to the anterior side of the body.
• Dorsal side. It is the upper side of the body which is away from the substratum during locomotion.
• Ventral side. (L. Venter = belly). It is the lower side of the body which is towards the substratum during locomotion.
• Lateral sides. The right and left sides of the body are called lateral sides.

Body cavity

• Coelom. The body cavity is bounded externally by the parietal layer of the peritoneum and internally by the visceral layer of the peritoneum.
• Coelomate (Eucoelomate). The animals that possess true coelom. (True coelom is a cavity between the body wall and visceral organs and must be formed from mesoderm) Example Bryozoa.

Based on origin, coelom is of two types :

• Schizocoel. When coelom is formed by splitting of mesoderm Example annelids, arthropods, and mollusks. The animals having schizocoelic coelom are grouped in Schizocoela.
• Enterocoel. When coelom is formed from the enteron ofgastrula Example echinoderms and chordates. Such animals are grouped in Enterocoela. Acoelomate. These organisms lack coelom. They include all members up to phylum Platyhelminthes.
• Pseudocoelomata Animals in which false coelom is present. Body cavity, if present, develops from blastocoel, for example- Rotifera, Nematoda. Haemocoelomatas.
• In Arthropods and mollusks, the true coelom is reduced and the body cavity is filled with blood and is called hemocoel, and animals are termed haemocoelomates.

Modes of Respiration

Modes of excretion

• Ammonotclism. When the main nitrogenous waste is NH3 the animals excreting ammonia are called ammonotelic animals. The water loss from the body along with ammonia is 300-900 ml/gm of NH3. It is found in aquatic animals Example Protozoans, sponges, coelenterates, crustaceans, echinoderms, and bony fishes.
• Ureotelism. The main nitrogenous waste is urea and the animals possessing it are called ureotelic animals. The loss of water along with urea is comparatively less. It is 50ml/ gm of urea. It is found in amphibians, mammals, and cartilage fishes.
• Uricotelism. The main nitrogenous waste is uric acid and animals possessing it are called uricotelic animals. Water loss is quite less and is just lOml/gm of uric acid. It is expelled as a semisolid paste. It is found in reptiles, birds, and insects.
• Mollusks like Limnaea, Unio, etc. are amniotic (expel amino acids) while certain bony fishes (especially teleosts) have trimethylamine as nitrogenous waste.

Cold-blooded or warm-blooded

1. Homeothermal or Endothermic (Warm-blooded animals).
2. In this, body temperature Is constant and does not change with the change in environmental temperature Example birds and mammals.
3. Homeothermal Or endothermic (Cold-blooded animals). In this, body temperature is not constant and changes with changes in environmental temperature.

These defend themselves in two ways:

1. Hibernation (Winter-sleep). In this, animals hide themselves in winter months and become inactive Example amphibians (frog; and lizards.
2. Aestivation (Summer-sleep). In this, animals hide in shady areas during hot summer months. amphibians.

Detailed Notes On Non-Chordates Classification For NEET

Blood Vascular System

1. Open type circulation Example Arthropods, mollusks.
2. Closed type circulation Example. Annelids and most of chordates.

Body Plan

1. Cell aggregate
2. Blind sac and
3. Tube in a tube body plan

Number of germ layers

• Diploblastic animals. In sponges and coelenterates, gastrula has two layers, outer ectoderm, and inner endoderm, so they are called diploblastic animals, for example, Porifers and coelenterates.
• Triploblastic animals. From flatworms to mammals, gastrula larva has three germ layers, outer ectoderm, middle mesoderm, and inner endoderm. So these are called triploblastic animals, for Example Platyhelminthes onward all phyla.

Reproduction

• Monoecious.When one individual of a species possesses both the male and female reproductive organs Example Pheretima, Taenia, Fasciola, etc. Hermaphrodite. It is a synonym or duplicate name of monoecious.
• Dioecious. When male and female reproductive organs are borne by separate individuals, the situation is called dioecious, for example- Man, Pila, Prawn, etc.
• Sexual dimorphism. If we can distinguish male and female individuals of a species by looking at their external features only, the phenomenon is called sexual dimorphism. Or, Males and females possess different shapes.
• PoIymorphism.The occurrence of at least tv/o, usually several, radically different body forms within colonial or social organisms.
• In unisexual animals, sperms and ova are derived from different animals, called cross-fertilization, In some bisexual animals, sperm and ovum of some animals fuse, called self-fertilization Example in Taenia.
• But in some bisexual animals, cross-fertilization occurs due to conditions: protandrous and protogynous. In protandrous conditions (Proto = first, android = male), testes mature earlier than ovaries Example leech, earthworm, etc.

In protogynous conditions (Proto =first, gynae = female), ovaries mature earlier than testes Example Scypha, and Herdmania (Sea squirt).

• Polygamy. When one male lives in the company of many females Example Struthio.
• Holoblastic Cleavage. The cleavage of the egg is complete; for example—in many invertebrates, amphioxus, amphibians, and mammals.
• Meroblastic Cleavage. The egg divides incompletely due to too much yolk in it The cleavage is confined to a limited portion of the egg, for example, Squids, insects, many fishes, reptiles, and birds.
• Metamorphosis. The larva undergoes certain changes to become adult, this process is called metamorphosis.
• Progressive Metamorphosis. When the larva is simple and becomes complex in the adult stage, for example- the Tadpole of a frog changes into an adult. Retrogressive Metamorphosis. When the larva is complex and more advanced than the adult.
• It loses its certain characters, for example –
• Ascidians. The larva has a well-developed notochord and nerve cord while these structures are absent and reduced respectively in adults.
  • Monogenetic life cycle. When a parasite completes its life cycle in a single host Example Ascaris.
  • Digenetic Life cycle. When a parasite completes its life cycle in two hosts.
  • Pheromones. Secretions of glands are released in the air. These generally act as sex attractants.
  • Autotomy. The ability of self-amputation.
  • Regeneration. Ability to make up lost parts.

Classification Of Animal Kingdom For NEET Phylum Porifera

Unique features

• The canal system consists of pores, canals, and chambers facilitating the continuous flow of water for nourishment, respiration, excretion, and reproduction.
• Cellular organization within the body.
• Lack of oral cavity and gastrointestinal tract.
• Choanocytes, also known as collar cells, line the diverse passageways and spongocoel.
• Existence of spicules, spongin fibers, or both.
• The free-swimming larvae, termed parenchymula (Lcucosolenia & Clathrina) and amphiblastula (Sycon), function as a primary mode of dispersal for this predominantly sessile phylum.

Classification Of Animal Kingdom For NEET Cells Of Sponges

• Choanocytes (also known as “collar cells”) flagellated cells which function as the sponge’s digestive system, are remarkably similar to the protistan choanoflagellates.
• The collar is composed of microvilli and is used to filter particles out of the water.
• The beating of the flagella of choanocytes’ creates the water current that enters the spongocoel.

• Pinacocytes. Form the pinacoderm, the outer epidermal layer of cells. This is the closest approach to true tissue in sponges.
• Porocytes. Tubular cells make up the pores in the sponge body through the mesohyl.
• Myocytes. Modified pinealocytes control the size of die and pore openings and thus (lie water flow.
• Archaeocytes (or microcytes). They are totipotent cells that can transform into. They also have a role in nutrient transport and sexual reproduction.
• Sclcrocylcs. Secrete calcareous or siliceous spicules that reside in the mesohyal.
• SpoiRocyles. Secrete spongin, collagen-like fibers which make up the mesophyll.
• Collcncytcs. Secrete collagen.
• Spicules. Stiffened rods or spikes made of calcium carbonate or silica are used for defense.
• Sensory anil nerve cells are absent in sponges.
• Spongioblasts. Spongin-fibre-secreting cells of sponges.
• Out of these, myocytes are derived from the dermal layer, while other amoebocytes are derived from the gastral layer.
• Cells are arranged in a gelatinous non-cellular matrix called mesohyal.

Position of Chomocytes

• Line the spongocoel in the Ascoiioid canal system.
• Line the radial canals in the Syconoid canal system.
• Line the flagellated chambers in the Lcticoitoid canal system.
• In the cavity of Eupleclella, a pair of crustaceans- Venusta spongicola lives till death.
• Prosopylc: An aperture between the incurrent and radial canal of Scypha.
• Apopyle: An aperture between a radial canal and an excurrent canal of Scypha.
• Geniniulation: Formation external buds in sponges.
• Gentmule: An internal bud of Spongilla. II is formed by a coat of spicules. It helps in perennation. Spicules- kinds.
  1. Rod-like or (long, short spear or club-like (excites)
  2. Three-rayed or Triradiate
  3. Tetaradiate
  4. Six rayed.
• Chemical nature.
• Calcareous or siliceous
• Costliest bath sponge – Spongia officinalis (natural sponge)
• Spongilla colony. Green in color.
• Gemmules are endogenous buds of sapodilla and help in asexual reproduction
• Euspongia. brown
• Spongia and Hippospongia provide bath sponges of commercial value
• The largest sponges belong to the class Demospongiae. A tropical logger-head sponge (Spheciospongia) forms a mass of over a meter in height and diameter
• Sponges are the lowest metazoans and arc placed in sub-kingdom Parazoa.
• Parazoology. Scientific study of sponges.
• Robert Grant. Coined the term Porifera.
• Ellis: Recognised the sponges as animals.
• The dermal ostia of sponges are analogous to mouths, while the osculum is analogous to the anus.
• The Mesogloea of the sponge is known as mesohyal or mesenchyme.
• Spongilla is a common and widely distributed freshwater sponge,
• Ieucosolenia is one of the simplest sponges.

Reproduction in sponges

Asexual reproduction

• By budding External/Exogcnous In budding, numerous archaeocytes collect at the surface and the placoderm bulges out to receive them. The bud so formed grows in an adult individual, ft either remains attached to the parent individual or gets detached and attached nearby to develop into an independent colony.
• Formation of gemmules (Internal/endogenous buds) All freshwater and some marine sponges (Ficulina, Tethya, Suherites, etc.) have a regular and peculiar mode of asexual reproduction by internal buds, called gemmules (Gr., gemma, bud).
• These eventually detach and develop into new individuals. Gemmules enable the sponges to tide over unfavorable conditions, such as excessive cold or draught, because they can withstand freezing and considerably greater degrees of desiccation than adult sponges.
• Fission-In some sponges, multiplication takes place by fission, throwing off parts of the body. The sponge is hypertrophied over a limited area, developing a line of weakness.
• Along this weak line, splitting occurs and a part is separated from the main parental body which develops into a new individual. By budding, this new individual takes the form of a colony.
• Formation of reduction bodies Another very unusual method of asexual reproduction is the formation of reduction bodies. Most freshwater and marine sponges disintegrate in adverse circumstances.
• The ailing sponge will usually collapse leaving small rounded balls, called reduction bodies.
• Each body consists of an internal mass of amoebocytes, covered externally by a pinacoderm. When favorable conditions return, these reduction bodies grow into completely new sponges.

Classification Of Animal Kingdom Non Chordates NEET Notes

Sexual Reproduction

• Sperms and ovum arc are derived from archaeocytes or choanocytes which undergo gametogenesis.
• Sperms are released outside through outflowing water and make their way into another sponge along with the ingressing water.
• Sperms arc carried by sperm-transit cells to the ovum.
• Fertilization is internal.
• The development includes amphiblastula or parencliymula larva.
• Amphiblastula is a hollow, oval larval stage, characteristic of many calcareous sponges (Example Scypha). Anterior one-half of amphiblastula bears flagella, whereas the posterior half does not.
• The parenchymula is a solid, oval, or flattened larval stage. It is characteristic of some calcareous, hexactinellid, and most demosopongians. The entire outer surface bears flagella.
• With the help of external flagella, the motile larvae escape from the parental body and swim for a few hours to many days. Finally, they settle down, become attached to some solid object, metamorphose, and grow into adults.

Classification Of Animal Kingdom For NEET Phylum-Coelenterata—(Cnidaria)

Unique features

1. Tissue level of organization.
2. Special kinds of stinging cells or cnidoblasts are meant for offense, defense, and food catching.
3. Diploblastic, radially symmetrical, and mostly show polymorphism.
4. The epidermis surrounds the cnidarian’s ‘stomach’ or gastrovascular cavity which functions as both mouth and anus. It is used both to ingest food and excrete waste.
5. It also serves along with the mesogloea as a hydrostatic supporting skeleton. Firm skeletons are only found among polyps, which produce lime for that purpose.
6. The gastrovascular system plays a role in the digestion and dispersion of food and the removal of metabolic waste.
7. It surrounds the gastrovascular cavity as well as its extension in the tentacles of polyps. Thus the gastrovascular system serves two separate functions, digestion, and transport.
8. Digestion is both intracellular and intercellular or extracellular.

Classification Of Animal Kingdom For NEET Kinds Of Nematocysts

• Penetrants or Stenoteles. They are the largest.
• Volvent or desmosomes. They are the smallest, used only for obtaining food.
• Small glutinanLs or Alrichous or his, Butt absent and help in fixing loan object.
• Large glulinants or Ifolotrichous isorhiza. The long thread is open at the free end. They slick to an object.

Classification Of Animal Kingdom For NEET Hydra

Features of Hydra

• It is a fixed animal and is found attached to submerged weeds and stones. Though it is fixed, it can move about when required. If disturbed, it contracts to a small spherical or oval mass.
• It is carnivorous as its food consists of small crustaceans and larvae of insects.
• Digestion is intercellular as well as intracellular.
• Hydra has a slender tubular body and exhibits distinct radial symmetry. The body is extremely contractile and length varies from 10 to 30 mm.
• The lower end of the tubular body is closed and this side is designated as the aboral or proximal end. This side of the body is named a foot or basal disc.
• It is used as a structure for attachment to the substratum and it helps in locomotion.
• The opposite end (the distal or oral end) is free and possesses the opening of the mouth, situated at the summit of a conical elevation called the hypostome or manubrium.
• The manubrium is usually surrounded by several tentacles. The tentacles are fine hollow processes and help in catching food.
• The mouth leads into the coelenteron which occupies the interior of the body. It is continuous with the cavities of the tentacles.
• The epidermis and Gastrodermis are the two cellular layers of the body wall of Hydra. In between these two layers is also present a non-cellular jelly-like mesogloea.
• The epidermis is the outer protective layer and cellular. It forms nearly one-third of the thickness of the body wall. It consists of the following types of cells:
  • Epitheliomuscular cells or
  • Musculoepithelial cells
  • Interstitial cells
  • Cnidoblasts or Nematoblasts
  • Nerve cells
  • Sensory or receptor cells
  • Germ cells.
• Nematocysts are of 4 types i.e. Penetrant (Stenotele), Volvcnt (Desmoneme), Glutinant streptoline (Holotrichous isorhiza), and Glutinant steroline (Atrichous isorhiza).
• Gastrodermis. It forms nearly two-thirds of the thickness of the body wall. It is always found forming the lining of the gastrovascular cavity. It consists of five types of cells:
  • The nutritive muscular cells
  • The secretory cells
  • The sensory cells
  • The nerve cells
  • The interstitial cells.

Classification Of Animal Kingdom For NEET Useful Information

• Leukart Gave the term coelenterata.
• Peyssonel (1723): Reported the animal nature of coelenterates.
• Coelenterates are commonly called cnidarians due to the presence of cnidoblasts, so the study of coelenterates is called cnidology.
• Coelenterata name is due to the presence of the coelenteron cavity.
• Obelia is a trimorphic and marine colony.
• Planula larva is formed during the life cycle of Obelia.
• Coelenteron is present which is known as a gastrovascular cavity.
• Cell differentiation and Physiological division of labor are distinct in Hydra.
• Digestion is extracellular as well as intracellular.
• Respiratory organs, Blood, vascular system, and excretory organs are absent.
• The epidermis and Gastrodermis are cellular layers and are separated by mesogloea.
• Mesogloea is the non-cellular layer that is secreted by the epidermis and gastrodermis.
• Obelia and Aurelia show an alternation of generation and phenomenon of metagenesis.
• The main stem of Obelia is called the stolon which gives rise to hydrorhiza which is attached to a substratum.
• Most probably Triclwplax represents the most primitive living metazoans.
• Totipotent interstitial cells are the characteristic of Hydra.
• When development starts, obelia is a monomorphic form having polyp only but later due to the development of blastostyle it becomes a dimorphic colony and finally medusae but over the blastostyle in a mature colony, then it becomes a trimorphic colony.
• Some coelenterates can paralyze people swimming in the seas. ‘Sea wasp’ a coelenterate is one of the most poisonous animals.

Metagenesis. In the life cycle of Obelia, there is regular alternation between fixed polypoid and free swimming medusoid phases, both of which are diploid. Such an alternation between two phases is called metagenesis.

In metagenesis, the adult polyp forms male or female medusae (diploid) asexually.

There are three principal asexual events:

• Budding Strobilation occurs when a medusa forms on the higher (oral) end of the polyp, and is common among scyphozoa finally, complete metamorphosis, from polyp to medusa form can also occur.
• Some coelenterates that show polymorphism are Obelia, Physalia, and Velella. Physalia shows excessive polymorphism having gastrozooids, dactylozooids, and gonozooids.
• In India, medusae of Aurelia are commonly found in coastal waters of Madras.
• In the development of Aurelia (a jellyfish), both planula (larva) and ephyra (larva) are present.
• Obelia. Seafur, a marine, sedentary, and trimorphic colonial coelenterate.
• It has 3 types of zooids: nutritive and flower-like polyp enclosed in a hydrotheca; long and cylindrical mouthless blastostyle enclosed in a gonotheca; and umbrella-like dust with gonads and developed as a bud on the blastostyle. It is commonly called zoophyte due to its plant-like appearance.
• Corals are skeletons secreting anthozoans, while sea anemones are anthozoans with skeletons.
• Coral reefs. A coral reef is a ridge in the sea and is formed of skeletons of the coelenterates called corals. It is mainly formed of skeletons of stony corals like Madrepora but is impregnated by skeletons of Millipore and Tubipora.

It is mainly formed of calcium carbonate. These are of 3 types (by Hyman, 1940):

• Fringing reefs. These extend from the shore up a distance of 400 meters into the sea.
• Barrier reefs. These run parallel to the shore but are separated from slower by a water body called a lagoon. The largest barrier reef Great Barrier Reef in the north-east coast of Australia and is 1920 km long.
• Atoll. It is circular coral surrounding a quiet water body called a lagoon. It is also called Coral Island.
• In India, Lakshadweep islands are formed of coral reefs.
• These are mainly found in warm (70°F) and shallow waters of tropical seas. The Pacific northeast of Australia is called the Coral Sea.
• Corallite is the skeleton of an individual coral, while coenosteum is the colonial skeleton and is called corallum when it is branched.
• Corallium rubrum. Also called red coral (moonga), while Meandrine is commonly called brain coral.
• Rhizostoma. A polytomous scyphozoan with many mouth-bearing structures called scapulets.
• Aurelia. Three larval stages in the life cycle: Planula (ciliated for dispersal), Scliyphistoma (represents reduced polypoid stage and forms ephyrae by transverse fission called strobilation), and ephyrae.

Important Non-Chordates NEET Questions With Answers

Classification Of Animal Kingdom For NEET Phylum—Acnidaria Or Ctenophora

• Phylum Ctenophora was established by Hatschek (1839).
• Phylum Ctenophora is also called Aaiidaria as these lack cnidoblasts.
• Gastrodes parasiticum is only an endoparasitic ctenophore.
• Mesogloea ofctenoplwres is of collenchyma nature (with many cells).
• Ctenophora is a small phylum of marine coelenterates like free swimming and biradially symmetrical animals having 8 meridional rows of ciliary comb ribs.
• They are popularly called comb jellies, sea combs, and sea gooseberries.
• Cnidoblast are absent except Eucldora rubra.
• They possess phagocytes or light-producing structures, therefore are luminescent.
• Tentacles, when present, are solid and possess adhesive cells called colloblasts (= lasso cells).
• Ctenophores are acoelomates.
• The body plan is intermediate between the blind sac and tube within the tube.
• Animals are usually monoecious. An immature ciliated stage larva called cydippid larva is found in some forms.
• Ctenophoria has two classes- denticulate (with tentacles), Example Hormiphora, and nuda (without tentacles), Example Beroe.

Classification Of Animal Kingdom For NEET Phylum- Platyheminthes

General Characters of Phylum Platylielmintlies

• Body form. Body dorsoventrally flat, unsegmented leaf or ribbon-like.
• Germ layers. Triploblastie animals, with three germ layers ectoderm, endoderm, and mesoderm.
• Habitat. Mostly parasites with some five living forms.
• Symmetry. Bilaterally symmetrical.
• Level of Organisation. Body organization is at the level of organ and organ-system grade.
• In parasites, forms suckers and hooks are present lor attachment to host tissues.
• Body cavity. True body cavity absent i.c. acclimate.
• Incomplete alimentary canal present. In the alimentary canal, the mouth is present but the anus is not present. In some endoparasites alimentary canal is absent.
• Respiration is aerobic in free-living forms and anaerobic in endoparasites.
• Excretion is mainly ammonotelic. For excretion special cells called flame cells or protonephridia are present.
• Nervous system. Due to capitalization, a nerve ring is present.
• Sense organs. Photoreceptors are present in free-swimming forms.
• Reproduction. The reproductive system is highly developed and bisexual. It is an adaptation of a parasitic mode of life.
• The life cycle is usually complicated. It is again an adaptation to a parasitic mode of life

Classification Of Animal Kingdom For NEET Parasitism

It is an association between different species in which one is benefited and the other is harmed. The organism which is benefited is called a parasite and the other that suffers is termed a host. It is interesting to note that hosts can live without parasites but parasites cannot survive without hosts.

Types of parasites

1. Temporary or partial parasites. These are animals that spend a brief period of their life as parasites and a major part as free-living forms.
   1. Examples: The Glochiditim larva of freshwater mussel is ectoparasitic on fishes for a short period, whereas the adult mussel is free living.
   2. Hymenoptera larvae are parasitic on caterpillars, whereas the adults are free-living.
2. Permanent parasites. They are parasites throughout their life.
3. Ectoparasite (External Parasite). They live on the surface Example Diplozoon indicum parasites on the gill of freshwater fishes.
4. Endoparasites. Many live inside the host’s body Example Taenia in the intestine, Paragonitim in the lungs, Polystomium in the urinary bladder Fasciola hepatica in the liver, and Schistosoma in the blood. They live in the host body, within the cells. (Cytozoic), tissue (histozoic) or cavities (coelozoic).
5. Monogenetic parasites (life cycle). Life history completed in a single host. Example Polystomum and Diplozoon.
6. Non-pathogenic parasites. They do not cause any diseased conditions in the host body.
7. Digenetic parasites. These parasites require two hosts to complete their life cycle.
8. The host in which the parasite grows into its adult phase is called final, definitive, or primary while the one that simply serves to transmit the parasite from one definitive host to the other is called intermediate, secondary, or vector host.
9. Accidental parasites. These are swallowed accidentally.

Examples: Soil and freshwater nematodes.

1. Mode of infection of helminth parasite
2. Swallowing of contaminated food.
3. Boring through skin Example Schistosoma.
4. Direct contact Example Diplozoon.

Adaptations of helminth parasite

Morphological Adaptation

1. Loss of organs. Locomotory organs, digestive organs, sense organs.
2. Continuation of pre-existing features. Thin flat body, shelled egg.
3. Development of new structure. Adhesive organs tegument, sucking pharynx, cyst wall around infective larvae.

Non-Chordates Classification NEET Previous Year

Physiological adaptations

1. Anaerobic respiration.
2. Secretion of anti-enzymes and mucus.
3. Evasion of the host’s immune system.
4. Chemotoxin
5. Excessive multiplication

Classification Of Animal Kingdom For NEET Fasciola Hepatica (Liver Fluke)

• Liver fluke lives as endoparasite in the bile ducts and canaliculi within the liver and remains attached by an oral and a ventral sucker (acetabulum).
• Upto 200 flukes may be present within a sheep. The mouth is situated in the oral sucker. No anus. Liver fluke is hermaphrodite (monoecious) but cross-fertilization takes place.
• There are two tests. Ovaries and vitelline glands are separate. Laurer’s canal is the temporary opening that receives the cirrus of the male during copulation.
• After fertilization eggs are laid in the bile ducts from where through the intestine they come out with the feces. The shell gland secretes the secretion which hardens to form the shell (capsule). Further development takes place in humidity.

Life Cycle of liver fluke

• The life cycle is digenetic, the primary host is sheep and the secondary host is a snail.
• Eggs enclosed in capsules develop into miracidium larva which hatches in water and enters into the body of a snail (in digestive glands).
• Miracidium will die if it does not reach a suitable host within 24 hours of hatching.
• It develops into sporocyst larvae which form at least two aerations of 5 to 8 media larvae.
• Each media larva forms 14 to 20 cercaria larvae by its ns cells. Cerearia larvae come out of the body of the snail and swim with their tail.
• After some time they get attached to leaves of water vegetation and become encysted to the next larva i.e. metacercaria.
• When sheep feed on aquatic vegetation, metacercaria reaches the alimentary’ canal, where the cyst is dissolved by digestive enzymes and cercaria reaches the liver through the bile duct and develops into adult flukes.
• It causes fascioliasis or liver rot, anemia, and excessive edema of the jaws. Heterogamv.
• A kind of alternation of generations in liver fluke, in which there are alternations between sexual phase represented by adult worms and parthenogenetic generations represented by media and cercariae larvae. Polyembryony.
• In Liver fluke, the germ cells present in larval form are not eggs but they are diploid cells derived by mitotic divisions from propagatory cells separated from zygote. Thus zygote produces many larvae. It is termed as polyembryony.

Classification Of Animal Kingdom For NEET Schistosoma Haematobium

Blood fluke

Commonly known as a blood fluke. It is a digenetic parasite, the primary host is man and the secondary host is Limnea (snail). It causes schistosomiasis or Bilharziasis. Males and females are separate. Females live in the gynaecophoral canal of males.

Classification Of Animal Kingdom For NEET Taenia Solium (Tapeworm)

1. This lives as an endoparasite in the digestive tract where it is anchored to its mucosa by its scolex and absorbs the host’s digested food.
2. It is found in all those parts where the pig is domesticated.

1. Its body is opaque, flat, long, and ribbon-like, measuring 2.8 meters on average.
2. The body is divided into Head (Scolcx), the unsegmented neck, and the segmented strobiln.
3. The head has 4 muscularsuckers and two rows of hooks around the rostellum. The hooks and suckers are meant for attachment. The strobila has about 800-900 segments known as probiotics. These proglottids at the posterior end are sexually mature and known as grnvids.
4. The gravids break off from the body and pass out with feces. This loss of gravity is made good by the neck which makes new proglottids.
5. The body walls consist of a cuticle that rests on the body musculature that binds mesenchyme.
6. Respiration is mainly anaerobic or anoxybiotic.
7. The excretory system consists of lateral longitudinal canals, secondary canals, capillaries, and flame cells.
8. Tapeworm is bisexual (hermaphrodite). Each proglottid has a large number of testes and a single bilobed ovary. Fertilization is internal and the zygotes are stored in a very much-branched uterus. There may be upto 30,000 zygotes present in the items of one gravid. The zygotes are covered with a thick layer of shell.
9. Life Cycle. The gravids break off (apolysis) from the body and pass out with feces.
10. If these feces are eaten by a pig, the zygotes reach into the alimentary canal of the pig. Each zygote produces an embryo with 6 hooks known as a Hexacanth embryo.
11. The hexacanth embryo along with the shell is known as the oncosphere. The shell gets dissolved in the intestine of the pig, the hexacanths come out.
12. These hexacanths pierce the wall of the intestine and enter into the bloodstream. The hooks disappear and each hexacanth embryo changes into a bladder-like structure known as a bladder worm (Cysticercus larva).
13. These larvae now settle into the voluntary muscles of pigs. If a man eats such a pork which is highly infested with bladder worms, they reach into the intestine of the man and one of the bladder worms develops into a Taenia.
14. Parasitic adaptation. Locomotory organs and digestive system absent Hooks and suckers present for attachment to host’s intestine Cuticle permeable for absorption of digested food from host’s intestine, Produces some anti enzymes which neutralize the enzymes and Taenia does not get digested itself, The osmotic pressure of the body fluids of Taenia is the same as that of man.
15. Because there is one Taenia found in the intestine of one person hence it is bisexual, It produces a very large number of ova because there is a lot of wastage of ova in the feces, and Sense organs are very much reduced.

Classification Of Animal Kingdom For NEET Taenia Saginatathe, Beef Tapeworm

Taenia saginata is comparatively longer than Taenia solium and the scolex does not have rostellum and hooks. It has 4 muscularsuckers only. There may be upto 2000 proglottids present in the body. The intermediate hosts are cows and buffaloes. It causes Taeniasis and cycticercosis.

Classification Of Animal Kingdom For NEET Important Information

Turbellarians (Planarians).

• Dugesia is with a triangular head with two auricles, while Planaria is with a truncated head.
• The pharynx is protrusible through the mouth.
• Rhabditis: Rod-like bodies in the epidermal cells. Their secretion is probably protective and adhesive in function.
• The Planarian eye is an inverse eye in which light has to pass through the photoreceptors and then fall on pigment cells.
• Bipalium: Only terrestrial planarian.
• Morpholactic regeneration. One part of the body can form the whole body.
• Neoblasts: Cells of planarians that help in regeneration.

Trematodes (Flukes).

• Schistosoma (Blood-fluke). It is the only unisexual fluke found in the veins of man. Female is present in the gynaecophoral canal (a groove on the ventral side) of males. It causes schistosomiasis characterized by intestinal disorders. It is also called Bilharzia.
• Opisthorcliis sinensis. Chinese liver fluke of man.
• Paragonimus. Lung fluke of man.

Animal Kingdom Non-Chordates NEET Topic Wise Study Guide

Fasciolopsis buski: Intestinal fluke of man.

• Monogenetic flukes. With a monogenetic life cycle, for Example Diplozoon (ectoparasite of gills of fishes), Gyrodactylus.
• Digenetic flukes. With two hosts in the life cycle Example Fasciola, Schistosoma, etc.
• Prohaptor. Anterior sucker of flukes.
• Opisthaptor. Posterior sucker of flukes.
• Amphistomous flukes. Fluke with 2suckers, one at each end of the body Example Paramphistomum.
• Fasciola is with two testesand one ovary. Miraridium and cercaria are in free-swimming stages, while sporocyst and redia are inside the snail.

Cestodes (Tapeworms)

• Taenia saginata (Beef-tapeworm). It is found in the small intestine of man. The secondary host is a cow. Human infection is by taking undercooked measly beef. Its scolex is without hooks and rostellum while strobila is formed of about 2,000 proglottids.
• Taenia has a bilobed ovary and about 200 follicular testes.
• The world population suffers more from Taenia saginata than T. solium due to more beef eaters.
• Bothria: Longitudinal groove-like adhesive organs of tapeworms.
• Suckers. Cup-like adhesive organs.
• Onchosphere. Encapsulated larvae are found in the uterus of gravid proglottids.
• Apolysis. Loss of gravid proglottids from the posterior end of the body.
• Strobilation. Formation of new proglottids from the neck, also called
  pseudometamerism.
• Echinococcus. Hydatid worm. Its hydatid cyst shows exogenous as well as endogenous budding. Parasite of small intestine of dogs, cats, etc. It has only 3-4 proglottids.
• Diphyllobothrium. Largest tapeworm (18 m).
• Hymemolepis. Dwarf tapeworm (2-4.5 cm). It is a monogenetic tapeworm of man.
• Dipylidum. Dog tapeworm.
• Scolex is the adhesive part of tapeworms.

Classification Of Animal Kingdom For NEET Phylum Aschelminthes

General characters of Phylum Ascheliminthes

• Body form. Cylindrical body but circular, in outline in cross-section.
• Germ layers Triploblastic animals with three germ layers.
• Habitat, Some are free living and many are ectoparasites and endoporasites of animals as well as plants.
• Level of organization. Body organization is at the level of an organ system.
• Symmetry. Bilaterally asymmetrical.
• The body is covered with thick, tough, and spiny cuticles.
• The epidermis is syncytial.
• In the body fixed number of cells are present.
• The alimentary canal is complete and straight.
• Circulatory system absent.
• Respiratory system absent.
• Respiration is aerobic in free-living forms and anaerobic in parasitic forms.
• Special types of sense organs known as phasmids are present.
• The nervous system is well developed with a nerve ring, ganglia, and nerve cords.
• The excretory system is simple, formed of specially shaped cells.
• Excretion is ureotelic.
• Reproduction. Sexes are separate with a well-developed reproductive system.
• Shows sexual dimorphism. Usually, females are longer than males.

Detailed Notes On Non-Chordates Classification For NEET

Classification of Phylum Aschelminthes.

• Class Nematoda (Sub-class Phasmida).
• Phasmid present, pouch-like sense organs and act as chemoreceptors present] Dracunculus medinensis (guinea worm), Rhabditis.
• Sub-class Aphasmida. Phasmids absent Example Trilobius, Trichinella (Trichinia worms) Trichuris (whipworm)
• Class 2. Nematophora e.g, Paragordius,
• Class 3. Rotifera Example, Philondina, Rotaria.
• Class 4. Kinorhyncha Example Echinoderes.
• Class 5. Gastrotricha Example Chaetonotus, Macrodasys.
• Class 6. Pripaulida
• Class 7. Acanthocephala

(These classes are now treated as separate phyla)

Classification Of Animal Kingdom For NEET Ascaris Lumbricoides (The Round Worm)

• This is the common roundworm found as a parasite in the intestine of man and also in pigs, cattle, sheep, and squirrels.
• Sexes are separate and show sexual dimorphism. The male is comparatively smaller than the female. The male measures 15 to 30 cm long with the posterior end curved, whereas the female measures 20 to 40 cm long and straight. Cloacal aperture is present in males whereas in females separate anus and vulva are present.
• There are 4 distinct lines present on the body of Ascaris in the form of folds known as Epidermal cords. (Dorsal, Ventral, and two lateral cords).
• The mouth is situated at the anterior end surrounded by 3 lips known as Dorsal Lip and 2 Ventro-lateral lips. The lateral papilla and amphid are present on each ventrolateral lip.
• Amphid is the chemo and olfactory receptor.
• Excretory pores are present above 2 mm away from the anterior end.
• The body wall consists of a cuticle (non-cellular), syncytial ectoderm, and longitudinal muscle.
• Highly vacuolated, fluid-filled pseudocolor present.
• The alimentary canal starts from the terminal mouth surrounded by 3 lips. The mouth opens into the pharynx which is bulb-shaped and lined by cuticles. From the pharynx begins the intestine which leads into the narrow rectum which opens outside through the anus.
• The alimentary canal of Ascaris is mainly concerned with absorption ofthe food rather than digestion.
• The excretory system is more or less H-shaped. Two longitudinal excretory canals are joined by a transverse canal.
• Male reproductive organs consist of a single long and coiled thread-like testis that opens into the vas deferens of almost the same diameter.
• The vas deferens opens into a wide seminal vesicle. It leads into a narrow ejaculatory duct which opens outside through the cloaca. There are present a pair of pineal spicules which help during copulation.
• Female Reproductive Organs are didelphic i.e. double. There are a pair of thread-like ovaries. Each ovary continues into a slightly thicker tube known as the oviduct The two oviducts open into a broad and muscular utero. The two uteri join together and open into the vagina. The vagina opens outside through the female gonopore or vulva, which is situated on the ventral side about one-third of the length from the anterior end.
• Life History. The sperms of Ascaris are amoeboid which brings fertilization of eggs in the uterus.
• The fertilized eggs are covered with 3 layers. A female Ascaris lays about 15,000 to 200,000 zygotes each day in the small intestine of a man. These zygotes pass out with the human feces.
• The larvae are known as rhabdoid larvae or first stage juveniles which are formed within the zygotes.
• The first-stage juveniles still live within the eggshell and molt after 10 days to produce 2nd stage juveniles (infective stage about 0.2 to 0.3 mm long).
• After rupturing the shell, 2nd juveniles come out and wander in the body for 25 days, undergo second and third molting in the alveoli of the lungs, and by the time 4th stage juveniles are formed again and reach the alimentary canal where they grow into adults. In the intestine, they molt for the fourth time and grow into adults in about 2 to 3 months.

Classification Of Animal Kingdom For NEET Life Cycle Of Ascaris

Classification Of Animal Kingdom For NEET Wuchereria Bancrofcit

Human filarial worm

• It is predominantly located in tropical climates.
• Wuchereria is a dimorphic intercellular endoparasite of humans.
• Wuchereria inhabit the lymphatic arteries and lymph nodes of humans.
• Wuchereria bancrofti, sometimes referred to as Filaria bancrofti, induces elephantiasis disease (Filariasis).
• In filariasis, lymphatic tubes and glands become inflamed and clogged, resulting intissue enlargement due to the accumulation of lymphatic  fluid. Infection by Wuchereria (filaria) occurs via the Culex mosquito.
• The life cycle is digenetic in nature.
• Both male and female forms entwine with one another.
• Culex fatigans and Culex pipiens act as secondary hosts for Wuchereria.
• Female Wuchereria produce sheathed embryos known as microfilariae.
• Microfilariae are elongated, slender entities encased in a translucent sheath.
• Microfilariae enter the superficial blood circulation at midnight and are transmitted into the body of a mosquito (Culex) during the bite.
• Microfilaria transforms into sausage-shaped larvae within the thoracic musculature of mosquitoes.
• Microfilariae undergo two molts within the thoracic muscles of mosquitoes, transforming into elongated, slender forms.
• Long, slender microfilariae represent the infective stages that are subsequently transmitted within the primary host, namely humans.
• Significant pharmaceuticals include Antimony and Arsenic compounds, which eliminate both adult forms and microfilariae.
• The lifespan of Wuchereria is four to five years.

Ancylosloma (Hook worm)

• Ancylosloma is the worm of man.
• Ancylostoma is monogenetic.
• The Cloaca of the male is surrounded by a copulatory bursa. Hookworm causes Ancylostomiasis in which a person suffers from acute (severe) anemia.
• The free larval stage is found in the life cycle of hookworms.

Trichuris trichiura (whip worm). Endoparasite of caecum and large intestine of man. Heavy infection causes diarrhoea and anemia.

Rhabditis maupasi. A free living soil nematode.

Loa (Eye worm): Commonly found in subcutaneous tissue in Africans. These pass across the eyeball.

Enterobius (Oxyuris). Pinworm. An endoparasite of the large intestine of man. It is monogenetic. It causes enterobiasis characterized by sleeplessness, digestive and mental disorders, abdominal pain, etc.

Classification Of Animal Kingdom Non-Chordates NEET Notes

Trichinella (Trichina worm). An intestinal endoparasitic worm ofman. Reservoir hosts are pigs, dogs, cats, etc. Larvae become spirally coiled in the voluntary muscles. It causes trichinosis characterized by nausea, muscular pain, etc.

Dracunculus (Guinea worm). An endoparasitic worm of subcutaneous tissue is digenetic and its secondary host is Cyclops. It causes guinea worm disease characterized by itching, diarrhea, nausea, vomiting, etc. It is the earliest known nematode and was earlier called the “Fiery Serpent.”

Classification Of Animal Kingdom For NEET Phylum Annelida

General characters of Phylum Annelida

• Triploblastic animals.
• Bilaterally symmetrical.
• Found in water and moist soil.
• Mostly free swimming, some are parasites
• True coelom is present for the first time in the animal kingdom. Coelom is shizocoel.
• True metameric segmentation is present.
• Annelids have a complete and straight alimentary canal.
• Annelids show tubes within the tube body plan.
• Locomotory organs are setae or parapodia or suckers.
• In the body wall, both circular and longitudinal muscles are present.
• Blood vascular system closed type.
• Respiratory pigment is hemoglobin, which is dissolved in plasma.
• Respiration either by moist body surface or parapodia or gills is present.
• Nephridia are present for excretion. Nephridia are metanephridia.
• The nervous system consists of a nerve ring, double, solid, ventral nerve cord, and segmental ganglia.
• Sense organs are of many types such as photoreceptors, olfactory receptors, etc.
• Sexes usually united i.e., hermaphrodite.
• Reproductive organs develop from coelomic epithelium.
• Development may be direct or indirect.
• The larva, if present, is a trochophore larva.

Unique features

1. Metameric segmentation
2. True coelom lined by mesodermal epithelium filled with coelomic fluid which acts as a hydraulic skeleton
3. Excretory and osmoregulatory structures are nephridia
4. The presence of circular and longitudinal muscles both in the body wall and wall of the gut
5. Closed circulatory system with respiratory pigment dissolved in plasma
6. Development may be direct or larva if present is trochophore larva.

Classification Of Animal Kingdom For NEET Important Information

Class Oligochaeta

• Chloragogen cells or yellow cells of earthworms are analogous to vertebrate liver cells.
• The brown color of earthworms is due to the pigment porphyrin present in the body wall and coelomic fluid.
• It protects the body from bright sunlight. Lumbricus is the earthworm of Europe and North America; Megascolex is found in South India while Eutypliaeus is found in the Gangetic plain of North India.
• Clitellar glands are maximum in clitellar segments and secrete ootheca.
• Setae are absent in the first, clitellar and anal segments.
• The coelomic fluid of earthworm is with five types of coelomocytes: Phagocytes (largest sized and most numerous); leucocytes, melanocytes, circular cells, and yellow cells.
• Yellow cells, also called chloragogen cells, store glycogen granules so are analogous to hepatocytes of the liver. Some suggest that these are excretory in function.
• Typlilosole: A large-sized fold in the middle part of the intestine and increases the face area of absorption.
• In earthworms, there are 4 pairs of hearts, one pair in each of the 7th, 9th, 12th, and 13th segments. The anterior two pairs of hearts are called lateral hearts, while the posterior two pairs of hearts are called latero-oesophageal hearts.
• Scptail nephridia of earthworm mid nephridia of Nereis arc called metanephridia as each opens In coelom by nephrostome.
• Earthworm In excretion (40% tire).
• In the nerve cord, there are 4 giant nerve fibers which help in reflex actions,
• Receptor organs of earthworms are formed of modified epidermal cells.
• The male reproductive system is formed of two pairs of testes (one pair In each of the 10th and Ith segments) and is enclosed in respective testes sacs (two in number). Prostate glands are one pair while accessory glands are 2 pairs (one pair in each of the 17th and 19th segments).
• The female reproductive system includes one pair of uncovered ovaries (in the 13th segment). Spermal Uecae is 4 pairs (one pair in each of the 6th, 7th, 8th, and 9th segments) and stores the sperms received during copulation.
• Tubifex (blood worm) A darkly red-colored oligochaete (with a large amount of hemoglobin in blood) that can survive even in a highly 02- deficient and polluted fresh-water body.

Important Non-Chordates NEET Questions With Answers

Class Polycliaeta

• Nuchal organs. Olfactory and chemosensory pits on prostomium behind the eyes. These help the worms to detect the prey.
• Gonads are temporary structures and develop only during the breeding season.
• Nephromixia. Nephridia which act as excretory as well as genital ducts. The term nephrotoxic was coined by Goodrich (1945).
• Epiloky. Transformation of a non-sexual into a sexual polychaete. The posterior part of the body with gonads and parapodia with leafy outgrowths and oar-like setae is called epitoke, while the anterior non-modified part is called matoke.
• Trochophore larva is with two ciliated bands: Prtotrocli and telotroch, which help in dispersal
• Aphrodite. Commonly called sea mouse, while Polynoe is called scale worm.
• In Eunice (Potato worm), epitoke is regenerated several times.
• Chactoplertis (Paddle worm) A tuberculous, marine polychacte. It has 3 fan-like notopodia in the middle part of the body which beat and maintain a water current.
• Arenicola (Lugworm), Amphitrite, and Tcrcbella are polychaetes that have gills for respiration.
• Nereis has a closed circulatory system but no heart.

Class Hirudinea

• luminaria granulosa (Indian cattle leech) :
• The skin of leech is with numerous mucus-secreting gland cells.
• A clitellum is formed by the 9th, 10th, and 11th segments during breeding season.
• Nephridiopores are 17 pairs (one pair on the ventral side of each of the 6th to 22nd segments).
• Leech has 3  jaws (jaw with a single row of denticles).
• Hirudin. An anticoagulant in the saliva of leech.
• The crop is the largest part of the gut. It is 10-chambered and stores the blood.
• True coelom in leech is reduced and enclosed in testes sacs and ovisacs.
• Leech has 17 pairs of nephridia and are of 2 types:
• 11 pairs of testicular nephridia (one pair in each from the 12th to 22nd segment).
• 6 pairs of pre-testicular nephridia (one pair in each of the 6th to 11th segments)
• Ciliated organs of nephridia have no excretory function but manufacture coelomic corpuscles of the haemo coelomic system.
• Leech is ammonotelic in excretion.
• Leech has 11 pairs of testis sacs, one pair in each segment from the 12th to the 22nd segment, but has only one pair of ovaries in the 11th segment.
• Spermatophore. Bundle of sperms.
• Pontobdella (skate sucker) is a marine leech that sucks the blood of skates, rays, and sharks.
• Hirtido medicinalis The medicinal leech of Europe is a fresh-water leech.
• Phlebotomy. Method of blood-letting to suck the impure blood by applying an icon-hungry leech to the skin.

Classification Of Animal Kingdom For NEET Phylum Arthropoda

General characteristics of Arthropods

• Habitat. Arthropods are found in all types of habitats. They may be aquatic or terrestrial the insects have taken to the aerial mode of life.
• Germ layers. Triploblastic i.c. ectoderm, mesoderm and endoderm.
• Symmetry. All arthropods show bilateral symmetry, having distinct dorsal, ventral, and lateral sides.
• Body plan. Like all higher animals arthropods show tube-within-tubc plan of the body.
• Level of organization organ system level.
• Exoskeleton. The body is covered by a chitinous exoskeleton which may be impregnated with calcium salts. Chitin is a polysaccharide. The chitinous exoskeleton is largely responsible for the success of arthropods to live on land, it protects the body and prevents the loss of water.
• Body Regions. The body is usually distinguished into the head, thorax, and abdomen.
• The presence of the head is an important advancement and is called cephalisation. In many species, the head and thorax are fused to form a cephalothorax, for Example, Prawn, and Crayfish.
• Segmentation. Arthropods are segmented externally. The segments in the anterior region get fused to form the head. However, the body cavity is not partitioned by septa.
• Jointed Appendages. The most important feature of the phylum is the presence of paired jointed appendages. They are modified according to their function. For example, insects have three pairs of jointed legs on the thorax which are used for walking, in crayfish and prawns they are modified for swimming. Some of them are specialised for feeding while others are applied for sensory and reproductive purposes.
• Wings. The insects are the only non-chordates that can fly due to the presence of two pairs of wings arising from the dorsal side of the thorax. However, some insects, for example, Silverfish and Head louse lack wings. The wings are simply outgrowths of the body wall.
• Digestive system. The alimentary canal opens at both ends of the body and is distinguished into three regions, the foregut, mid-gut, and hindgut.
• Body Cavity. The body cavity is called hemocoel. It lacks a regular layer of mesodermal lining and contains blood.
• Circulatory system. The circulatory system is of open type. The blood directly lies in the body cavity, and there are no closed vessels.
• Respiratory organs. Aquatic forms respire by gills. The terrestrial arthropods such as insects breathe employing certain branched tubular organs called tracheae which ramify throughout the body, and communicate to the outside by certain openings called spiracles.
• Excretory organs. The excretory organs in insects are the malpighian tubules. In crustaceans, the excretion is by green glands or antennary glands.
• Nervous system. It resembles that of annelids and consists of a brain and ganglionated ventral nerve cord.
• Sense organs. The sense organs are well developed. They include compound eyes for sight, and sensilla for smell, hearing, and taste.
• Reproduction. Arthropods reproduce only sexually. Sexes are separate, and the male and female are externally distinguishable.
• Fertilization is internal. Life history usually involves a larva or nymph. The larva (or nymph) later changes into an adult. The phenomenon is called metamorphosis.

Classification Of Animal Kingdom For NEET Unique Features

1. Jointed appendages are modified for performing various functions such as feeding, walking, flight, sensory; copulation, egg laying, etc.
2. The hard exoskeleton of chitinous plates for protection and also provides a hard surface for attachment of muscles
3. Tracheae for respiration in most eases. In other forms gills, book gills, and book lungs act as respiratory organs.
4. Malpighian tubules or coxal glands as excretory organs for excretion.
5. Compound eyes are formed of optical units called ommatidia.
6. Presence of hemocoel

Classification Of Animal Kingdom For NEET Mouth-Parts Of Insects

1. Biting and chewing type Orthopteran Example Grasshopper, cockroaches, crickets, silverfish, Booklice, bird lice, earwigs, termites, Hymenoptera, especially caterpillars, bedbugs, and beetles.
2. Piercing and Sucking
   1. Mandibles, Maxillae constitute needle
   2. Labium – hollow grooved channel Example Mosquitoes
3. Chewing and lapping type Example Honey bees
4. Sponging type Example houseflies and other flies
5. Siphoning type. Butterflies and moths.

Classification Of Animal Kingdom For NEET Metamorphosis In Insects

1. No metamorphosis or Ametabolous development Example silverfish, springtails egg Adult
2. Incomplete metamorphosis or hemimetabolous development
   • Egg → Naiad→ Adult
   • Example Mayflies, Dragonflies, stone flies
3. Gradual metamorphosis or paurometabolous development
   • Egg→ nymph → Moulting Adult
   • Example Grasshopper, Aphids, Stink bug
4. Complete metamorphosis or Holometabolous development
   • Egg → Larva Pupa → Adult
   • Example Housefly, Mosquito, butterfly

Animal Kingdom Non-Chordates NEET Topic-Wise Study Guide

Hormonal Control

1. Brain hormone (BH) – (LIPID)
2. Activates the corpora cardiaca—a component of retrocerebral complex.
3. Prothoracicotrophic hormone (PTTH) is secreted in corpora cardiaca which in turn stimulates Prothoracic glands.
4. Prothoracic gland hormone (PGH) (Ecdysone) Trigger molting.
5. Juvenile hormone (JH)
6. Secreted by corpora allata (non-sterolic lipid). Promotes metamorphosis.

Larvae Of Crustaceans

1. Nauplius—Cyclops. Ii may give rise to intermediate larval forms
2. Mctanauplius—Apus
3. Protozoea—Penacus
4. Megalopa—True crab
5. Glamcothel—Hermit crab
6. Schizopod—Lobster
7. Cypris—Lcpas, Sacculus
8. Alima—Squilla
9. Phyllzosoma—Spiny lobster
10. Zoea.

Classification Of Animal Kingdom For NEET Economic Importance Of Insects

1. Poisonous Insects. Examples are Honeybees, wasps, hornets, fire ants, bed bugs, mosquitoes, and a few lepidopterous and other larvae.
2. Disease carriers
   1. Species of Anopheles spreads Malaria.
   2. Culex mosquitoes spread nematode worm Filaria which causes Filariasis.
   3. Stergomyia mosquitoes spread Yellow fever
   4. Taparus fly spread surra disease among horses and camels.
   5. African sleeping sickness by tse tse fly (Glossina)
   6. Housefly spreads diarrhea, cholera
   7. Fleas spread bubonic plague
   8. Bed bugs and Body Louse spreads Relapsing fever
3. Productive Insects
   1. Honey and bees wax by Honey Bee (Apis indica)
   2. Wax produced by scale insects
   3. Commercial silk by silkworms (Bombyx mori)
   4. Lac is produced by lac insect (Kerria laced)
   5. Shellac secreted by coccidae.
   6. Dyes and tannin are obtained from cochineal dried bodies of certain scale insects.
4. Insects in Medicines
   1. Cochineal Insect contains carminic acid concern, myricetin, fat, and fatty acids used for neuralgia and whooping cough.
   2. Browfly larvae are used in treating the decay of the tissue.
   3. Cantharidine oil obtained from blister beetle,
   4. Bods’ extracts of the cocoon of silk moth used for treating leucorrhoea,
   5. Bee venom is used for
      1. Arthritis and
      2. Antivenom for snake bite
      3. Honey. Natural Antiseptic used to cure ulcers.
      4. Bee wax. Base for ointments.

Classification Of Animal Kingdom For NEET Important Information

• Larvae of the genus Chironomus (an insect) are called blood worms. They have red blood. The red color of these larvae is due to hemoglobin.
• In coastal areas like Konkan Maharashtra of India, the red and black species of scorpions are deadly poisonous. Their venom is fatal.
• Honey is flower nectar mixed with the saliva of bees and is a natural antiseptic.
• Bees communicate by complex dance.
• Royal Jelly—a substance secreted by honey bee workers.
• Termites are social and polymorphic insects.
• Termites form large nests called crematoriums.
• Usually the larger an animal is, the longer it takes to grow up. One exception is the 17-year cicada (an insect), which spends a very long time as a larva.
• In spiders, the web is secreted by the last body segment.
• The thread of the spider web is stronger than steel thread.
• The endoskeleton is present in the head and thorax of the cockroach. The abdomen has no endoskeleton.
• In all insects the intervals between two eedysis (casting of skin) is known as the stadium and the form assumed by the young insect during a stadium is called an Instar.
• Mites are parasites of animals as well as plants
• Fireflies or glow worms bear light-producing organs upon their abdomen. Light is emitted at short intervals by both males and females as a visual signal to attract each other for copulation.
• Gambusia is a larvivorous fish that feeds on up larvae of mosquitoes.

Classification Of Animal Kingdom For NEET Selected Arthropods Class Crustacea

• Daphnia. Its body is covered by a bivalved carapace and is commonly called a water flea.
• Cyclops Commonly called one-eyed monster (with the simple median eye). The female is with ovisacs and carries the eggs. Serves as a vector of Dracunculus nematode.
• Cypris. Commonly called mussel shrimp. A microscopic fresh-water crustacean showing cutaneous respiration.
• Barnacles are sedentary crustaceans Example Liyas. Called a Ship or goose barnacle. A pedunculate crustacean. Carapace is with 5 calcareous plates.
• Balanus. Called Acorn or Rock Barnacle. A sessile crustacean. Carapace is with 5 calcareous plates.
• Sacculina. Called a root-headed barnacle. An ecotoparasite of crab and highly degenerated crustacean due to retrogressive metamorphosis. Induces the development of female characters in infested male crab, called parasitic castration. Squilla is commonly called mantis shrimp as preys upon small marine fishes, crustaceans, mollusks, etc.
• Palinums. Marine spiny or rock lobster as carapace with many spines, Edible.
• Eupagurus (Hermit crab): Shows proto-cooperation with sea anemone (Adamsia).
• Palacmon (Prawn).
  • P. carcinus is giant prawn (90 cm), while P. Lamarr is dwarf prawn (2.5-5 cm).
  • Statocysts (one pair) are organs of balance and lie in the basal segment of each
    antennule.
  • Epimeron. A scaly plate which joins an appendage with the pleuron.
  • Biramous appendage. An appendage in which a basal segment called
  • Protopodite gives two outgrowths: inner endopodite and outer exopodite.
  • Uniramous appendage: When protopodite gives rise only endopodite but there is no exopodite.
  • Cephalic appendages of Prawn are 5 pairs (one pair each of antennules, an tennae, mandibles, maxillidae and maxillae).
  • Thoracic appendages are 8 pairs (5 pairs of legs and 3 pairs of maxillipeds).
  • The digestive gland of crustaceans is hepatopancreas which combines the functions of the liver, intestine, and pancreas.
  • All the gills of Prawn are Phyllobranchcs (gill axis with 2 rows of leafy gill lamellae).
  • The heart of a Prawn is arterial as it receives and distributes oxygenated blood.
  • Prawn shows apposition or mosaic vision in bright light and superposition vision during dim light.
  • Prawn fishery: Capturing of prawns from natural resources as well as their culture.
  • Prawn is a rich source of proteins and A and D vitamins but has low fats. Pcnaeus indicus (about 23 cm. long) is the most important commercial prawn species in India.
  • Lobster tail. The abdominal region of spiny lobsters is used as food.
  • Central Marine Fisheries Research Institute is located at Narakkal (Cochin).
• Oniscus. Only terrestrial crustaceans.

Class Insecta

Sub-class Diplura

• Eleven segments in the abdomen of both immature and adult. Segmented antennae.
• Cerci present, Malpighian tubules absent or vestigial. Primarily wingless. A widely distributed order living in concealed habitats, often in the soil.
• Sub-class Protura Abdominal segments were added successively through post-embryonic growth, making a final complement of eleven segments plus a posterior telson.
• Antennae absent. Malpighian tubules are present but rudimentary. Primarily wingless. Minute, whitish insects widely distributed, found in moist litter, bark, etc.

Sub-class Collembola

• Abdomen with six segments only, usually with three sets of appendages, a ventral tube on segment 1, and a retaining hook on 3 which functions with a powerful springing organ on segment 4. No metamorphosis.
• The tracheal system is absent in most species. No malpighian tubules. Primarily wingless. Living in soil, leaf litter, decaying vegetable material, under bark, etc. Known as the springtails.

Sub-class Apterygota

• Primarily wingless. The metamorphosis from juvenile to adult is slight or absent.
• Mandibles have only a single point of articulation (except in the family Machilidae of the order Thysanura). Usually possessing pregenital abdominal appendages.

Detailed Notes On Non-Chordates Classification For NEET

Cockroach

• Indian cockroach, Blatta orientalis, is dark-colored and small-sized. Female Blatta has vestigial wings.
• The native place of Periplaneta is tropical Africa and not America.
• Burmeister (1838) : Gave the generic name Periplaneta.
• The mouth parts of the cockroach are downward called hypognathous heads.
• The neck, also called the cervical, is not a true body part but is an extension of the arthrodial membrane.
• The labrum is the upper lip, while the labium or second maxilla is the lower lip.
• The hypopharynx is the tongue hanging between the mouthparts.
• Each leg is formed of 5 podomeres. The last podomere is called tarsus.
• Fore wings are thick and leathery and act as tegmina or wing covers.
• Hind wings are the flight organs of cockroaches. Folded like Japanese fans.
• Anal cerci of cockroaches are with auditory receptors.
• The antennae of cockroaches are olfactory and tactile.
• Trichogen cells are seta-secreting cells of hypodermis.
• The rate of heartbeat is 49 times.
• The heart of a cockroach is tubular and 13-clambered.
• Cockroaches and other insects are uricotelic.
• Urate cells of the fat body show excretion by storage.
• Compound eyes show only apposition or mosaic vision. No superposition vision.
• Male cockroach has 3 gonapophyses, called phallomeres, and act as external genitalia.
• Female cockroach has 3 pairs of gonapophyses which act as an ovipositor.
• Each ovary is formed of ovarioles.
• The nymphal stage is called the instar, while the interval between two molts is called the stadium.
• Ecdysis is controlled by ecdysone, a steroid hormone produced by prothoracic glands.
• An adult insect is called an imago and is formed due to the absence of the juvenile hormone of corpora allata of the nymph.
• Cimex lecttilaris (Bed bug). It is an ectoparasite of man, nocturnal in activity, san granivorous (piercing-sucking mouth parts) in feeding, and is found in crevices of cots, etc. The body is sub-circular, flat, and wingless. Each leg ends in two claws. Its bite causes sleeplessness.
• It also spreads germs of typhoid, plague, kala-azar, relapsing fever, etc.
• Pediculus (Head louse). An ectoparasite of man; found glued to the body hair, sanguivorous in feeding with piercing-sucking type mouth parts; spreads typhus fever. The body is flat and wingless.
• antennae are reduced. Mouth parts are piercing-sucking type. Each leg ends into a single claw.
• Pteris (Butterfly). Cosmopolitan insect, diurnal in activity, feeds upon nectar with siphoning type mouth parts, female is oviparous.
• The development includes caterpillar larva and involves complete metamorphosis.
• The body is long and slender. The Head has knobbed antennae, compound eyes, and mouth parts. Thorax has 3 pairs of legs and 2 pairs of wings. The wings have black marks.
• Mayflies. The mayflies are soft-bodied insects with delicate, membranous wings bearing numerous veins and cross-veins, the hind wings much smaller.
• Adults are short-lived, with mouthparts vestigial, short bristle-like term.ro,
• 1 pair of long cerci with many segments, with or without a median caudal filament; adults uniquely preceded by a winged, pre-adult instar.
• Nymphs are aquatic, and active, with paired cerci and a median caudal process, and feathery tracheal gills in most abdominal segments; almost entirely herbivorous.
• Mierotreme (Tennile or white ant). A colonial, polymorphic, and social insect, found in nests called termitaria in woods, 5 castes in the colony (queen, drone, worker, soldiers, and nnsufes); show symbiosis with multiflagellate protozoan Triehonympha.
• Poccilocerus pietus (Ak Grasshopper). It is diurnal, herbivorous (on Ak leaves by chewing-type mouth parts), and flying and jumping (with large-sized senatorial metalegs).
• The female is oviparous and egg-containing cocoons are deposited inside the burrows with an egg-laying apparatus called an ovipositor. The development includes gradual metamorphosis. It produces sound by rubbing the forewings together.
• Crickets. Crickets are medium to large-sized insects, with large prothorax and usually jumping hind legs. Winged or wingless, forewings somewhat hardened to form wing covers (tegmina). Mouthparts mandibulate.
• Cerci is usually short and unsegmented. Females generally with well-developed ovipositor.
• Often with specialized auditor)’ and sound-producing (stridulating) organs. Most numerous in tropical regions, generally worldwide in distribution.
• Generally herbivorous, a few carnivorous.
• Sympctnnn (Dragonfly). It is a diurnal, good flier, and carnivorous (flies and mosquitoes) insect.
• The development includes an aquatic larva called naiad and incomplete metamorphosis. Each forewing has a black spot called pterostigma.
• It is also called a mosquito hawk.
• Damselflies. Damselflies are strong-flying, predacious insects with long, rather narrow wings bearing many veins and cross-veins, hindwings similar to or larger than forewings. The thorax is characteristically modified with legs moved forwards and wings moved backward by tilting the thoracic segments; the abdomen is long and narrow. Generally large insects; a fossil species had a wing span of over 60 cm. Nymphs aquatic, active, predator)’.
• Musea domcstica (Housefly). It is a diurnal and a good flier insect. It feeds upon liquid foods (saprophagous) with its sponging type mouth parts having a fleshy proboscis.
• Hindwings are reduced and are called halters. These act as balancers. The development includes legless maggot larva and complete metamorphosis.
• Aphis brassicae (Aphid). It is a serious plant pest of mustard. It sucks the plant sap with its piercing and sucking-type mouthparts.
• It shows a symbiotic relationship with the ants which are called ant corns. It secretes “honeydew” through their cornicles (honeydew tidies). Tire females are viviparous and reproduce by parthenogenesis.
• Stone pies. Tire stone flies are moderate to rather large, soft-bodied insects with membranous wings, folded over the back at rest, hindwing the larger with a large anal lobe. Antennae are long and hair-like; mouth parts are weak, and mandibulate.
• Abdomen usually with a pair of long cerci. Nymphs are aquatic, active, with long antennae and cerci, and tracheal gills on the thorax, sometimes on the head to abdomen; living only in well-aerated water, mostly vegetarian diet.
• Stick insect and leaf insect. The stick and leaf insects are large, usually of elongated form less commonly flattened, mimicking twigs or leaves. Prothorax is short, and mesothorax is often lengthened. Winged or wingless, forewing often short and hard, and Mouthparts mandibulate. Cerci is short and unsegmented. The ovipositor is small, and concealed. Predominantly tropical distribution; herbivorous.
• Silkmoth. A single cocoon of silkworm provides about 300 metres of silk thread and about 12500 cocoons provide about half a pound of silk. The rearing of silkworms on mulberry plants is sericulture.
• A female lays about 300-500 eggs. In temperate countries, female lavs diapause (dormant) eggs during winter. Caterpillar larva undergoes four molts.
• The pupa is also called chrysalis. India is second in the world in the production of mulberry silk. Central Silk Research Institute is located at Mysore (Karnataka)
• Honey bee. Mouth parts are chewing and lapping types adapted to suck nectar and to mold wax. Prolegs of worker bees with pollen brushes, mesolegs have pollen spurs while metalegs have pollen combs, pollen packers, and pollen baskets.
• Domestication of honey bees is called apiculture while boxes used are called apian/. Domesticated spp.
• include. A. indica (mainly used), A. dorsata, A.florea and A. mcllifera. Inscoutbees, waggle dance was first reported by Karl von Friesch (1956).
• Cicada (Seventeen-yearlocust). With opisthognathous (backward directed head). Not true locust as both pairs of wings are alike (no tegmina). Male producers a very loud and whistling sex call. The metamorphosis period extends upto about 17 years.
• Bugs. The bugs are small to large insects, usually with two pairs of wings, tire forewings of a harder consistency than the hind pair, either uniformly hardened (Homoptera) or with the apical part membranous (Heteroptera).
• Mouthparts modified for piercing and sucking; labium forming a grooved rostrum or snout, containing two pairs of piercing stylets (mandibles and maxillae).
• Many species feed on the sap or cell contents of plants, while others are predatory. Some are important vectors of plant and animal diseases. Distribution worldwide.
• Beetles. Forewings are completely thick and called elytra while hindwings are membranous for flight. Larva has only true legs and is called gnib Examples are Coccinella (Ladybird beetle), Scarabaeus (dung beetle), and Sitophilus (rice weevil — weevil is a grain beetle).

Other Arthropods

• Limulus (horseshoe crab). a living-fossil representative. it is a marine, fossorial, nocturnal, and carnivorous arthropod. locomotion is walking, swimming, and jumping type. body is divisible in cephalothorax (prosoma) and abdomen (opisthosoma).
• cephalothorax is covered by a horseshoe-shaped carapace and has one pair of chelicerae and 5 pairs of legs.
• abdomen has a long spike-like telson at the posterior end and is used for jumping. it is also called “living sil” (about 190 million years old).
• Ticks and mites are parasitic arachnids.
• Scorpion was picturized by Walt Disney in “Living Desert.”
• Mites. Sarcotes (Human itch mite).
• Ticks. Dermacentor (Dog tick), Exudes (Sheep tick), etc. Ticks act as vectors of rocky mountain fever, relapsing fever, etc.
• Muga silkworms feed on Moms.

Classification Of Animal Kingdom For NEET Phylum Mollusca

Characters of Phylum Mollusca

• Body form. The body is a differently shaped head with visceral mass and foot present.
• Habitat Molluscs are generally aquatic (marine as well as freshwater) some of them, for example, slugs and terrestrial while others, for example, Pila (Apple Snail) are amphibious, that is, live in water as well as on land.
• Germ layers. Mollusks are triploblastic animals showing the organ-system level of organization.
• Symmetry. They may be asymmetrical, for Example snails, or may show bilateral symmetry, for Example, Freshwater mussels and cuttlefish.
• Level of organization organ system level of organization.
• Body plan. They show a tube-within-tube body plan. The body cavity includes hemocoel and reduced coelom.
• Body division. The mollusks have soft bodies which are differentiated into three regions foot, visceral hump mass, and head.
• The head bears eyes and sensory tentacles. The foot is the locomotory organ. The visceral hump is the main part of the body and contains various viscera, mainly the alimentary canal, digestive glands, and the circulatory system.
• Mantle and Mantle cavity. The visceral mass is covered by a soft and generally leathery covering called mantle or pallium. Between the visceral hump and mantle lies the mantle cavity which contains the gills and some portions of digestive and reproductive systems.
• Shell. The presence of a hard shell outside the body is a characteristic feature of most die mollusks. The shell is formed of calcium salts and is secreted by the mantle. It varies in shape and size.
• It is spirally coiled in snails (conchs and couriers). In oysters and mussels, it is formed of two equal valves. The shell is light and internal in cuttlefish, while it is absent in some mollusks, for Example, slugs.
• Respiration. The organs of respiration include one or two pairs of gills for aquatic respiration. Aerial respiration through the pulmonary sac. Mantle also plays a role in the process.
• Circulatory system. It is well developed and is of open type.
• The nervous system is well developed. It consists of ganglia, connectives, and commissure.
• Excretion through the renal organ.