NEET Biology Notes – Kingdom Protista

NEET Biology Kingdom Protista

Protists show remarkable variations in cell organization, patterns of cell division and life cycle. The occurrence of organisms with flexible lifestyles justifies the erection of the intermediate eukaryotic kingdom.

Characters of Protists

1. This kingdom includes diverse kinds of mostly unicellular and primarily aquatic eukaryotes.
2. They are eukaryotic organisms having typical eukaryotic cell organelles such as nuclei, mitochondria, ER, Golgi bodies, plastids etc.
3. The mode of nutrition is absorptive, ingestive or photo-autotrophic.
4. Mostly bear eukaryotic flagella composed of 9 + 2 internal microtubular structures.
5. Protists may be motile or non-motile. Protists show mainly three types of mechanisms
   of locomotion.
6. Sarcodine protists move with the help of pseudopodia. Flagellate protists move with the help of flagella and in other groups of ciliata locomotion is with the help of short-sized, hair-like cilia.
7. They may be haploid or diploid.
8. Reproduction is asexual as well as sexual.
9. Asexual reproduction occurs by binary or multiple fission or spore formation. It
   involves mitosis only. Sexual reproduction in protists involves syngamy and meiosis.
10. They may show zygotic meiosis or gametic meiosis.

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Major Groups of Protists Dinoflagellates (Pyrrophyta)

• They have two distinct unequal flagella. The cell wall is divided into plates. They reproduce asexually.
• Some are phosphorescent. Dinoflagellates are unicellular, photosynthetic protists which store starch or oils as their reserve food material.
• These are brown-red (due to xanthophyll pigment) and are characterised by the presence of a transverse groove (girdle) which divides the cell into two semi-cells.
• The cellulosic cell walls sometimes form structured plates called theca, conferring upon them an armoured appearance.
• Out of the two flagella emerging from the groove, one lies in the longitudinal direction, while the other lies transversely in a furrow between the plates.
• Several dinoflagellates exhibit bioluminescence (fire algae). The species of Gonyaulax and other dinoflagellates produce toxic blooms (red tides) in the ocean.
• The toxins may get concentrated in the tissues of animals (shellfish, oysters etc.).
• Dinoflagellates exhibit some prokaryotic characteristics (absence of histone protein, simpler mitosis, centromere and spindle absent) as well as eukaryotic characters (cell organelles bounded by a membrane, 9 + 2 arrangement of microtubules in flagella).
• Whorling Whips. Dinoflagellates, due to spinning caused by the activity of transverse flagellum (in cingulum/annulus) and longitudinal flagellum (in sulcus).
• Dinoflagellates, diatoms and euglena-like flagellates are protistan algae or photosynthetic protists. They account for over 80% of CO2 fixed in the biosphere.

Characteristics Of Protista NEET

Diatoms

The diatoms are the major producers in the seas. They lack flagella. They float in water due to the presence of lipids in them. They have overlapping cell walls with deposition of silica. Their fossils are known as diatomaceous earth.

They are diploids and reproduce sexually as well as asexually. The main features of diatoms are:

1. Diatoms are unicellular, noh-flagellate golden-brown algae. Their cell wall (frustule) nude up of the overlapping halves (upper kitchen and lower hypothec) like a soap tvv |vtn divh. and impregnated with silica.
2. Reserve food material in diatoms is in the form of lipid/volutin. Light storage lipids keep the cell afloat.
3. Sperms of diatoms have a single whiplash flagellum.
4. The oil in vv hale blubber, in fish and shark liver oils are believed to be the condensates from oil droplets originally present in the diatoms.
5. The good walls of diatoms are resistant to natural degradation. Hence, huge deposits of diatom frustules (diatomaceous earth) occur in the world- which are powdered and used in toothpaste and metal polish.
6. Diatomaceous earth is also used as an absorbent for nitroglycerine to make explosives and for filtration of liquids, especially in sugar refineries.
7. The diatom cell walls have thicker and thinner areas producing a complex series of ‘markings’ on the cell surface.
8. Diatoms reproduce asexually by cell division which occurs more frequently during midnight or early morning hours.
9. In a population of diatoms, the average size goes down as the division progresses. The original size is restored by the auxospore formation.

Euglena-like flagellates (Euglenoids)

Euglena-like flagellates are found in freshwater. They are covered by a pellicle as the cell wall is absent. They bear one or two flagella. They have a myxotrophic mode of nutrition.

1. Euglenoids are naked (cell walls absent); 1/2/3 flagella arise from an invagination at the anterior end of the cell.
2. Pyrenosomes. In euglenoids, a chloroplast contains a proteinaceous body or pyrenoid.
3. The latter has a central clear area or pyrenophore with a disc-shaped pyrenosome on either side.
4. A paramylum shell is formed over it. Paramylum granules also occur freely in the cytoplasm.
5. Euglenoids show both plant-like and animal-like characteristics.
6. A photosensitive eye spot senses the intensity and direction of light and helps in phototactic.

Slime moulds

Slime moulds may be acellular or cellular. They glide as a mass of protoplasm on decaying vegetable matter, ingesting food particles. The moving strands of protoplasm are called plasmodium in acellular slime moulds and pseudoplasmodium in cellular slime moulds.

1. Cellular slime moulds (Example; Dictyostelium) are uninucleate, haploid, naked amoeboid a large number of these aggregate to form slug (pseudoplasmodium) — the cells of the slug behaving as one unit without losing their individuality. Hence, these exhibit a primitive type of multicellularity. There occurs a division of labour among the aggregating amoebae. This aggregation of individual cells coupled with the division of labour confers upon them die name ‘communal slime moulds’.
2. The acellular slime moulds are characterised by the presence of a multinucleate, free-living, naked amoeboid mass of protoplasm (plasmodium) which may be a minute, homogeneous protoplasmodium or divided into vein-like network (phaneroplasmodium Plmarum). Under dry conditions, the plasmodium gets transformed into sporangia. Thread-like sterile structures (papillitis the sporangia help in the dispersal of spores.
3. Slime moulds show both fungus-like (spore production) and animal-like (ingestive nutrition) characteristics.
4. The fructifications or fruiting bodies of slime moulds are of three types-
   1. Sporangia. One to several thousand sporangia develop on a single plasmodium.
   2. They may be stalked or sessile, globose, cylindrical or cup-shaped and variously sculptured.
   3. lasrnodiocarps. These are mostly sessile and develop around some of the main veins of plasmodium. They are variously shaped.
   4. Australia. They are large, sessile, globose or hemispherical structures that resemble a mass of fused sporangia.
   5. Capillitia Sterile threads in sporangia of acellular slime moulds for dispersal of spores.
   6. Communal Slime Moulds. Cellular slime moulds due to the formation of pseudoplasmodium by coming together of numerous myxamoebae.

Characteristics Of Protista NEET

Protozoan Protists

1. Protozoan protists are classified into four
2. Foraminifera (Example Globigerinare giant, multinucleate sarcodines protected by
   a many-chambered external shell made up of calcium carbonate.
3. These produce thread-like extensions (branched through the pores in the shells to capture their The fossils of foraminifers (shells) are usually found in the regions of the earth containing petroleum.
4. Radiolarians are giant multinucleated sarcodines (several cm. in diameter), having an internal skeleton of silica.
5. Helicozoans are beautiful, freshwater sarcodines covered by a shell of silica. These give out filopodia for capturing prey.
6. Sporozoans are parasitic protozoans which form spores e.g. Plasmodium (Malarial parasite.) They form spores as sporozoites at some stage of their life cycle.
7. Ciliates have cilia all over their body. Cilia are used for locomotion and feeding.
8. Ciliates have specialised organelles for performing a variety of their functions. The defence organelles flask-shaped, trichocysts are used to paralyse prey. Trichocysts also help in the anchorage of the ciliates during feeding.
9. Ciliates exhibit nuclear dimorphism i.e. micronucleus for reproduction and macronucleus for controlling body functions.
10. Binary fission is the main mode of reproduction. Some ciliates as Paramecium reproduce sexually by conjugation.
11. The fossils of foraminifers (shells) are usually found in the regions of the earth containing petroleum.
12. Radiolarians are giant multinucleated sarcodines (several cm. in diameter), having an internal skeleton of silica.
13. Helicozoans are beautiful, freshwater sarcodines covered by a shell of silica. These give out filopodia for capturing prey.
14. Sporozoans are parasitic protozoans which form spores e.g. Plasmodium (Malarial parasite.) They form spores as sporozoites at some stage of their life cycle.
15. Ciliates have cilia all over their body. Cilia are used for locomotion and feeding.
16. Ciliates have specialised organelles for performing a variety of their functions. The defence organelles flask-shaped, trichocysts are used to paralyse prey. Trichocysts also help in the anchorage of the ciliates during feeding.
17. Ciliates exhibit nuclear dimorphism i.e. micronucleus for reproduction and macronucleus for controlling body functions. Binary fission is the main mode of reproduction. Some ciliates as Paramecium reproduce sexually by conjugation.

NEET Biology Kingdom Protista Amoeba Proteus

Important points

1. Amoeba are living grey-coloured, asymmetrical protozoan with a size of about 0.25 to 0.60 mm long.
2. The body of an Amoeba is bounded by a single-layered, thin, elastic living membrane called a plasma membrane or plasmalemma.
3. The body consists of protoplasm differentiated into a centrally placed nucleus and cytoplasm. The cytoplasm consists of two distinct regions the outer ectoplasm and the inner endoplasm.
4. The ectoplasm is thin, clear and transparent. It is said to be protective in function.
5. Endoplasm is inner, granular translucent. The endoplasm can be differentiated into two regions by their physical nature i.e., an outer stiff viscid zone called plasma gel and inner more fluid called plasmasol.
6. The endoplasm contains a contractile vacuole, many food vacuoles, globules and crystals.
7. In amoeba process of digestion takes place first in an acidic medium and then in an alkaline medium.
8. Pseudopodia of amoeba are tipped by hyaline caps.
9. The contractile vacuole is a clear bubble-like spherical structure present in the outer part of the endoplasm meant for osmoregulation. Suspended in the endoplasm are endoplasmic reticulum, ribosomes, mitochondria, Golgi bodies and Iysosomes.
10. The nucleus is dense and disc-shaped. It is situated more or less near the centre. It is bounded by a nuclear membrane. Inside the nucleus lies nucleoplasm.
11. Scattered in the nucleoplasm are a large number of chromosomes. It also contains one or two nucleoli (Sing— Nucleolus). The nucleus controls the vital functions of life.
12. Locomotion with the help of pscudopodia.
13. The single-celled body performs all vital functions of life.
14. It has a holozoic mode of nutrition. Ingestion takes place by import, invagination, circumfluence and circumvallation. Digestion of food takes place inside food vacuoles.
15. Excretion and respiration take place on the general surface of the body.
16. Reproduction by asexual means only maybe by binary, multiple fission or
    sporulation.
17. Cyst formation during unfavourable periods also helps in dispersal.
18. Amoeba was first observed by R.R. Holf inI755, and H.I. Hirschfield described the details in 1862.

NEET Biology Kingdom Protista Entamoeba Histolytica

1. It is pathogenic, photo/oan and belongs to class Carolina (sarcosine)
2. It is a human parasite and inhabits the large intestine and lower part of the small intestine.
3. It feeds on erythrocytes and worn-out cells.
4. It is irregular in shape with a single blunt pseudopodium.
5. The contractile vacuole is absent.
6. A single rounded nucleus with a fine peripheral layer of chromatin granules and many food vacuoles present.
7. Reproduction is asexual.
8. The cysts are quadrinucleate.
9. Infection of human beings occurs by taking food and water contaminated with faecal matter containing cysts.
10. Entamoeba histolytica causes amoebic dysentery’ (enteritis).
11. It occurs in two forms, trophozoite form (magna form) and precystic form fminuta form).
12. Trophozoite form (20-30 pm) pathogenic form lives in mucosa and submucosa of the large intestine and may reach the liver, brain, and gonad. It is active, motile, feeding form having a single nucleus and food vacuole; cyst absent.
13. The precystic form (12-15 mm) non-pathogenic form lives in the lumen of the large intestine. It is inactive, non-motile, non-feeding stage have 4 nuclei and a cyst.
14. It was discovered in Russia by Losch (1875).

NEET Biology Kingdom Protista Plasmodium

Important points

• It is an important pathogenic parasite which causes malaria in man.
• The lift cycle is completed in two hosts, mini is the primary host of Plii simulitmi and the mosquito is the intermediate (secondary) host.
• When an infected female Anopheles mosquito sucks the blood of a man. it injects thousands of into humans along with its saliva.
• The sporozoites reach the liver cells within half an hour after a mosquito bite.
• The sporozoites multiply in the liver through asexual reproduction known as Schizogony.
• The complete two cycles in the liver are known as pre-Erythrocytic schizogony and exo-Krythrocytic schizogony.
• Piv-l-erythrocytic cycle produces a large number of cryptoincrozoitcs and the Exolirythrocytic cycle produces metacrypto merozoitcs. They are of two sizes and are called micro meta crypto merozoites and macro meta crypto merozoites.
• Metacry ptomerozoitcs attack the R.B. Cs in man and start the erythrocytic schizogony.
• The various stages in this cycle are the signet ring stage, the Amoeboid stage, the Trophozoite stage and the Schizont.
• Some yellow-coloured excretory granules are formed on the surface of RBC known as SchufTner’s dots. During this cycle, the haemoglobin of the RBCs breaks into Hacmozoin, a toxic substance.
• After die completion of the erythrocytic cycle the RBC ruptures and this causes shivering. The haemozoin is released out of the R.B.Cs and this causes malaria fever.
• After completing several erythrocytic cycles in the human, the parasites become so plentiful, that they either kill the host or may die themselves due to the struggle for existence. To avoid the chances of total extinction, the parasites go to the other host i.e. female anopheles mosquito.

The parasites make two types of gametocytes, in the human R.B.C.s i.e.

Microgametocytes (Male) and megagametocytes (female). These gametocytes are sucked into the crop of mosquitoes when it bites an infected person.

The male gametocytes produce male gametes (each one about 6) and female gametocytes produce one female gamete each in the lumen of the crop of mosquito. The process by which the male gametes separate away from the male gametocyte is known as exflagellation.

Fertilization takes place in the cavity of the crop of mosquito and a large number of zygotes are formed. The zygotes become spindle-shaped as they pass through the wall stomach and are known as vermiform or ookinete. Some zygotes fail to penetrate and are passed out with faeces.

Kingdom Protista Classification

The zygotes gel encysted in the stomach wall and are known as oocysts (sporocysts). There may be up to 5000 oocysts present on the stomach wall of one infected mosquito.

A large number of sporozoites are produced in the sporocysts by repeated divisions. This asexual phase is termed sporogony.

As the wall of sporocyst ruptures the sporozoites are released into the haemolymph and carried to salivary glands. During the sucking of blood, the sporozoites are injected into the body of a healthy person along with saliva.

NEET Biology Kingdom Protista Paramecium

Important points

Found in fresh water having decayed organic matter, bacteria, also known as slipper animalcule because its shape resembles like sole of a slipper and the size is about 0.3 mm.

The outer membrane is thick, inelastic and tough and is known as a pellicle.

• The oral groove extends from the anterior end and runs obliquely backwards making the body asymmetrical.
• There are rows of cilia present all over the body which arise from basal bodies (kinetoscope). The cilia are longer at the posterior end and known as caudal tuft.
• In Paramecium about 2500 cilia are present. Cilia beat in metachronous fashion and a cilium beats 10-11 times per sec. Caudal tuft cilia of paramecium are tactile.
• A row of cilia, kinetosomes and kinetodesmata constitute kinety. All the kineties form the infraciliary system or neuromotor system.
• The cytoplasm is divided into ectoplasm and endoplasm.
• A definite cell mouth is present known as the cytostome which opens into a funnel-shaped structure known as the cytopharynx, which leads to the endoplasm A temporary cytopyge or cell anus is present for the egestion of undigested food. Nutrition is holozoic.
• There are two contractile vacuoles present, one at each end of the body, meant for osmoregulation. Each contractile vacuole has a central reservoir and few radiating canals.
• Posterior contractile vacuole works more efficiently in paramecium.
• There are two nuclei which show nuclear dimorphism and make nuclear apparatus.
• They are situated in the endoplasm. Types of nuclei present are meganucleus and micronucleus. The meganucleus controls vegetative activities, divides by amitosis and contains trophochromatin (mostly RNA). The micronucleus controls reproductive activities, divides mitotically and contains dichromatic (mostly DNA).
• The species of paramecium having only three nuclei is Paramecium aurelia.

The food particle is taken through the cytostome into the endoplasm, where it becomes a vacuole known as a food vacuole.

The food vacuoles revolve in cytoplasm along an ‘8’ or ‘0’ shaped path. The movement is due to cyclosis (Rotatory streaming movement of cytoplasm).

In the ectoplasm is present a large number of sacs, all over the inner side of the pellicle known as trichocysts. These are discharged when Paramecium is stimulated and gets enlarged and thus plays a defensive role. They also help in anchorage.

Paramecium swims actively in water along a spiral path with the beating of cilia (effective stroke and recovery stroke). The spiral path results due to forward push, axial rotation and turning of the anterior end.

• Reproduction takes place asexually and sexually. Asexual reproduction takes place by transverse binary fission.
• Asexual reproduction, generation after generation leads to senility and ageing in paramecium. It resorts to sexual reproduction for rejuvenation.
• Sexual reproduction takes place by conjugation (amphimixis).
• Paramecium also overcomes senility by a cystotomy, autogamy, tendonitis and he mixes.
• In Paramecium bursaria, the green alga zoochlorella lives as a symbiont.
• Paramecium respond to electric current (galvanotaxis). If the current is weak it moves towards the cathode and if the electric current is strong moves towards the anode and then swells and disintegrates.

Paramecium contains self-duplicating bodies in cytoplasm mainly; Kappa particles other mutant particles are pi, lambda and ft particles.

Protista vs Monera NEET

NEET Biology Kingdom Protista Trypanosoma

Important points

1. It is a parasitic zooflagellate that mostly parasitizes the blood of vertebrates, first observed by Fonle (1901 ).
2. Common species of Trypanosoma which live as parasites in the blood of man are: T. gambiense (causes African Sleeping sickness spread by tse fly, Glossina pelpalis), T. rhodesiense. (causes fast African sleeping sickness) and T. cruzi (causes South American trypanosomiasis or Chagas disease, transmitted by a large blood-sucking bug).
3. The body is microscopic, elongated, leaf-like flattened, covered by pellicles and tapering at both ends. The anterior pointed end bears flagellum and the posterior end is blunt.
4. Trypanosoma shows polymorphism. The four morphic forms me viz.
   1. Leishmania form
   2. Lcptomqnuil form
   3. Crilhidial form
   4. Trypanosoma form
5. Tire trypanosomal form occurs both in the invertebrate and vertebrate host and crithidia is found in the invertebrate host only.
6. The cytoplasm contains numerous greenish refractile granules called volutin granules supposed to store food material.
7. Large oval vesicular nucleus present with nucleolus or endosome in the middle.
8. It obtains its food by osinotrophy from the blood.
9. Excretion and respiration through the general surface.
10. Sexual reproduction is unknown and it reproduces asexually by longitudinal binary fission.
11. The life cycle is completed in two hosts. The primary host is a man and the intermediate host or vector is a tsetse fly.
12. Infection to man is caused by the introduction of meta cysts by the bite of the tsetse fly.
13. Ablastin. It is the antibody produced during early infection of trypanosoma.
14. Meninges-encephalitis is caused by Trypanosoma.

NEET Biology Kingdom Protista Leishmania

Leishmania is also a digenetic, parasitic flagellate. The vertebrate host is man and the invertebrate host is sand fly of the genus Phlebotomus. Reserve hosts are cats and dogs. Leishmania is an intracellular parasite of man.

It is dimorphic. Two forms are:

1. Leishmania form
2. Leptomonad form

Leishmania donovani causes kala-azar or Visceral Leishmaniasis or dum dum fever in Africa, South America; India, and China. In Kala Azar Antimony compounds, like tartar emetic, sodium antimony tartrate, gluconate etc are used as drugs.

Leishmania tropica is a causative agent of Oriental sore. This species is more common in Africa and Central Asia.

NEET Biology Kingdom Protista Giardia

Monogenetic parasite of the human large intestine classified under the class Flagellata.

Giardia lamblia also referred to as Giardia intestinalis, is colloquially termed the “grand old man of the intestine.” Giardia induces “giardiasis” or dysentery in humans. Other species are also present in rabbits, dogs, cats, rats, guinea pigs, etc.

Trichomonas

• Trichomonas is a monogenetic, parasitic flagellate organism.
• Trichomonas is the predominant protozoan present in all vertebrate taxa. Trichomonas buccalis is located in the oral cavity and exacerbates pyorrhea.
• Trichomonas vaginalis is present in the vagina of a human female. It induces vaginitis and leucorrhea in females. Male individuals remain unaffected.
• Trichomonas hominis resides in the human large intestine, resulting in recurrent diarrhea.
• Helizoans (Solar Animalcules). The protists exhibit radiating axopodia reinforced by axial filaments. Illustration of Actinophrys. The latter exists in both freshwater and saltwater. It is heterotrophic.

NEET Biology Kingdom Protista Foraminiferans

Sarcodines possess one or more chambered calcareous shells, with extracapsular protoplasm that generates reticulopodia.

• Foraminifera ooze frequently accumulates at the seabed and, with time, transforms into limestone formations. The Egyptian pyramids are constructed from it.
• Petroleum-bearing formations frequently contain fossilized foraminifera.
• The White Chalk of the Cretaceous period and the Nummulitic Limestones of the Eocene epoch are of foraminiferal origin. Illustrations. Haphidium (also known as Polystomella), Globigerina.

NEET Biology Kingdom Protista Radiolarians

The snowlines are of considerable size and multifaceted. The chromosomal count is elevated.

• Aulocantha possesses the highest chromosomal count, totalling 1600. Radiolarians possess siliceous, structured capsules, with the intracapsular region containing nuclei and vacuoles.
• The extracapsular region contains pseudopodia (niopodia, axopodia, or reticulopodia).
• Radiolarian ooze resembles diatomaceous earth. Chalk was developed during the Ordovician-Carboniferous period, and siliceous powder was produced in Tertiary rocks. Illustrations. Acanthomctra, Ccillozoie.

Protista vs Monera NEET

NEET Biology Kingdom Protista Types Or Parasites

1. Permanent parasite. Parasitic for whole life, Example Entamoeba,
2. Obligate parasite. Unable to live outside the body of the host. Example viruses, Mycoplasma, (Hi) Facultative parasites, capable of living as a parasite (normally free-living), e.g. Clostridium tetani
3. Temporary parasite. Comes in contact with the host for only a part of the lifecycle,
4. Periodic parasite. Visiting host at a specific period of life history (W) Intermittent parasite. Temporary parasite visiting host at intervals. Example female Mosquito, Leech,
5. Incidental parasite. An organism becoming parasitic over host perchance/incidentally
6. Ectoparasite. On the surface of the host, Example Hydramoeba.
7. Endoparasite. Parasites live inside the body of the host It is of the following types.
8. Intracellular/Cytozoic parasite Endoparasite within host cells, Example Plasmodium.
9. intercellular/Histozoic/Tissue parasite. Endoparasite in spaces amongst cells Example Trichinella.

Body Fluid Parasite. In blood and other fluids, for example, Trypanosoma, (x) Coelozoic/ Cavity/Gut/Parasite. In the lumen/cavity of the body and organs, for Example; Giardia noxious/ Monogenetic parasite.

Passing life in a single host,  Heteroxenous/Heteroecious/ Digenetic parasite. Passing life in two hosts Hyper parasite.

Parasite over Parasite. Protozoan. Noscma is parasitic over protozoan Spliaerospora which is itself- parasitic overToad Fish. Pathogenic parasite, disease-causing (x iv) Non-pathogenic parasite.

Types of Hosts Primary Host. Host in which the parasite becomes sexually mature. Definitive Host.

Host of the adult parasite, Intermediate/Secondary Host. The host in which the parasite passes its larval stage is the collateral Host. Alternate host in which the parasite can subsist but cannot complete its life cycle.

• Coordinated ciliary beating may be metachronous (when cilia of transverse rows beat simultaneously) or synchronous (when cilia of longitudinal rows beat simultaneously). Among the protozoans, ciliates arc fastest in their locomotion and cover about 2 min per second.
• Medium in the food vacuole of Paramecium is first acidic and then alkaline.
  Nuclear dimorphism. Presence of two morphologically and physiologically different nuclei e.g. in ciliates.
• The Chromatin of the meganucleus is called trophochromatin,
  while that of the micronucleus is called idiochromatin.
• Trichocysts: Reported by Ellis. Pellicle, an extracellular coat of Paramecium is compa
  able to the skin of higher animals. Hill (1752) Discovered Paramecium. T.H. Sonneborn (1917) Reported that Paramecium caudatum has 16 syngens (varieties showing conjugation), while P. aurelia has 14 syngens.He also reported the cytoplasmic inheritance of Kappa particles in Paramecium.
• Ceratium is a member of dinoflagellates which are called fire algae as most of their members have luciferin compounds.
• Nosema was discovered by Pasteur (1865) causing the chronic disease ‘pebrine’ in silkworms and mosena disease in honeybees.
• Oriental sores also called cutaneous leishmaniasis because of the formation of 2-3 raised nodular lesions of about 2 5 cm in diameter on the skin of the exposed part of the body. Entamoeba gingivalis is not a causative agent of pyorrhoea but aggravates it, the causative agent is Trichomonas tenax. Chromatoid bodies stain easily with dyes which stain the chromatin therefore called so actually they are reserve food bodies formed in precystic forms which form cysts by secreting thin transparent cysts.
• The damaged cells of the spleen release lysolecithin which further damages RBC causing excessive release of bile pigments even in urine, therefore, called black water fever by Plasmodium falciparum. Coclozoic parasites are those which live in the alimentary canal or cavities of the host body, example; Entamoeba histolytica, Giardia lamblia and Balantidium coli.
• Schizogony is also called agamogony which is an asexual process not related to the sexual phenomenon. The product of schizogony generally grows into trophozoite.
• In certain species, capillitia have granules of carbonate of lime in capillitial threads called limeknots. The spores germinate into protoplasm exhibiting amoeboid movements before karyogamy therefore called myxamoebae.

Important Contributors

• Term Protista was given by Eamst Haeckel
• Leeuwenhoek (1674. 1675, 1681). First to see and sketch protozoan protists including Vorticella and Gia- cs> Golgi (1885). Studied erythrocytic cycle of Plasmonlia (from his stool). Goldfuss (1822). Separated protozoa from other animals. Von-Sicbold (1845). Found protozoans to be unicellular.
• The term unicellular was replaced with acellular by Dobel. Haeckel. In 1873, he differentiated protozoa from metazoa. Haeckel (1886) carved the kingdom protista for single-celled organisms. Lnvernn (1880). Discovered Plasmodium in erythrocytes.

Quanta to memory

• The earliest Protist was probably a flagellate. Flagella helped in moving the large eukaryotic cell through the water to where it could survive i.e. towards the light in the case of photoautotrophs and towards food in the case of heterotrophs. Flagellated cells are absent in red algae, higher seed plants and higher fungi. Several aquatic larval stages of animals are ciliated.
• The presence or absence, number, appearance, shape and place of insertion of flagella are important characteristics of protists. Proterospongia.
• A colonial protozoan protist having choanocyte-like flagellated and collared cells. It is a connecting link between Protista and Porifera. Auxospores.
• Rejuvescent spores formed in diatoms to correct the size which decreases with each binary fission. Schuffner’s granules are absent in the blood of a person infected with P. malariae. A few members of dinoflagellates, Gonyaulax and Gymnodinium produce the so-called ‘red tide’.
• A sudden increase in their number at the sea surface over a vast expanse makes the sea appear red. A toxin released by such large numbers may kill other marine animals like fish.
• Zooxanthellae. Dinoflagellates symbionts in other protists and invertebrates. Some dinoflagellates such as Noctiluca are phosphorescent (bioluminescent).
• They make the sea surface glow in the dark. Volvox colony is called coenobium as the zooids (individuals of the colony) are interconnected by protoplasmic strands. Noctiluca has photogenic granules with a light-emitting pigment called luciferin.
• It shows bioluminescence so is commonly called night light. The process of sexual reproduction allows greater variation in the progeny than asexual reproduction by mitosis.
• The rapid evolutionary advancements made during the one billion years of eukaryotic existence were believed to be made possible by sexual reproduction. Entamoeba gingivalis is found in 70% population and spreads through kissing. E. histolytica was discovered by Lamble however details regarding its pathogenicity were given by Losch.
• E. coli is found as an endocommensal in the colon of about 50% population. Egyptian pyramids are formed of Foaminiferan ooze. Aulocantha (a radiolarian protozoa) has the largest number of chromosomes (1600).
• Opalina is found as an endo commensal in the rectum of the frog. Vorticella is an epizoic protozoan and is commonly called bell-animalcule.

Reproduction In Protista NEET

NEET Biology Kingdom Protista Questions From Competitive Examination

Question 1. In amoeba, contractile vacuole is present :

1. Near trailing end
2. Near advancing end
3. In the middle of the body
4. Near the nucleus.

Answer: 1. Near trailing end

Question 2. Which of the following is incorrectly matched?

1. Culex pipiens—filariasis
2. Aedes aegyptii—yellow fever
3. Anopheles culinarians—leishmaniasis
4. Glossina palpalis—sleeping sickness

Answer: 3. Anopheles culinarians—leishmaniasis

Question 3. A contractile vacuole meant for osmoregulation is not found in:

1. Sarcodina
2. Sporozoa
3. Zooflagellata
4. Slime moulds.

Answer: 2. Sporozoa

Question 4. Malaria is caused by :

1. Virus
2. Bacterium
3. Sporozoan
4. Helminth.

Answer: 3. Sporozoan

Question 5. Which of the following is not connected with the reproduction of protozoans?

1. Cryptogamy
2. Schizogamy
3. Autogamy
4. Conjugation.

Answer: 2. Schizogamy

Question 6. Which of the following features is common in all protozoans?

1. Holozoic nutrition
2. Contractile vacuole
3. Pseudopodia
4. Eukaryotic organisation.

Answer: 4. Eukaryotic organisation.

Question 7. What of the following is not true of Euglena?

1. Presence of chlorophyll
2. Presence of proteinaceous pellicle
3. Presence of cellulose cell wall
4. Presence of flagellum.

Answer: 3. Presence of cellulose cell wall

Question 8. Which of the following is incorrect:

1. Omnivory
2. Holozoic nutrition
3. Photoautotrophy
4. Pseudopodia feeder.

Answer: 3. Photoautotrophy

Question 9. Which of the following features is common amongst euglena, amoeba, entamoeba and trypanosoma?

1. Binary fission
2. Holozoic nutrition
3. Contractile vacuole
4. Multiple fission.

Answer: 1. Binary fission

Kingdom Protista NEET Notes

Question 10. Which of the following unicellular organisms has a macronucleus for trophic function and one or more micronuclei for reproduction?

1. Euglena
2. Amoeba
3. Paramecium
4. Trypanosoma.

Answer: 3. Paramecium

Question 11. man in the life cycle of plasmodium is

1. Primary host
2. Secondary host
3. Intermediate host
4. None of these

Answer: 2. Secondary host

Question 12. Entamoeba histolytica differs from amoeba in the absence of

1. Pseacopodia
2. Contractile vacuole
3. Nucleus
4. Aectoplasm

Answer: 2. Contractile vacuole

Question 13. Myxomycetes are :

1. Saprobes or parasites, having mycelia, asexual reproduction by fragmentation, sexual reproduction by fusion of gametes
2. Slimy mass of multinucleate protoplasm, having pseudopodia-like structures for engulfing food, reproduction through fragmentation or zoospores
3. Prokaryotic organisms, cellular or acellular, saprobes or autotrophic, reproduce by binary fission
4. Eukaryotic, single-celled or filamentous, saprobes or autotrophic, asexual reproduction by fusion of two cells of their nuclei

Answer: 2. Slimy mass of multinucleate protoplasm, having pseudopodia-like structures for engulfing food, reproduction through fragmentation or zoospores

Reproduction In Protista NEET

Question 14. The thalloid body of a slime mould (myxomycetes) is known as:

1. Fruiting body
2. Mycelium
3. Protonema
4. Plasmodium

Answer: 4. Plasmodium

Question 15. What is common about trypanosoma, noctiluca, monocystis and giardia?

1. They produce spores
2. These are all parasites
3. These are all unicellular protists
4. They have flagella.

Answer: 3. These are all unicellular protists

Question 16. Which one of the following is a slime mould?

1. Physarum
2. Thiobacillus
3. Anabaena
4. Rhizopus

Answer: 1. Physarum

Question 17. Which one of the following pairs is wrongly matched

1. Yeast – ethanol
2. Streptomycetes – antibiotic
3. Coliforms- vinegar
4. Methanogens- gobar gas

Answer: 3. Coliforms- vinegar

Question 19. Single-celled eukaryotes are included in :

1. Fungi
2. Archaea
3. Monera
4. Protista.

Answer: 4. Protista.

Kingdom Protista NEET MCQs

Question 20. Which one of the following life cycle stages of the malarial parasite is responsible for the relapse of malarial symptoms?

1. Merozoite
2. Hypnozoite
3. Sporozoite
4. Gametocyte

Answer: 1. Merozoite