Human Health And Disease MCQ With Answers For NEET

Question 1. The population of Homo sapiens was 453 millions in:

1. 1550 A.D.
2. 4000 B.C.
3. 1650 A.D.
4. 8000 B.C.

Answer: 3. 1650 A.D.

Question 2. The average annual birth rate per 1000 individuals in developing countries is:

1. 10
2. 37
3. 19
4. None of the above

Answer: 2. 37

Question 3. The causes of uneven distribution of the world’s population in various regions may be due to the:

1. Geographical factors
2. Socio-economic factors
3. Demographic factors
4. All of the above factors.

Answer: 4. All of the above factors.

Question 4. Major areas of population concentration in the world are:

1. South East Asia, Japan, India
2. European countries
3. Latin American countries
4. North America.

Answer: 1. South East Asia, Japan, India

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Question 5. The density of a population in a given country is obtained by:

1. Dividing the total number of persons living in the country by the total land area
2. Dividing the total number of persons living in the country by the total fertile land area
3. Dividing the total number of persons living in the country by the total forest land area
4. Dividing the total number of persons living in the country by the amount of production of natural resources.

Answer: 1. Dividing the total number of persons living in the country by the total land area

Question 6. The population density of the Netherlands is higher than that of India because of:

1. More land area is there in the Netherlands as compared to India
2. A greater proportion of the inhabitable area is there in the Netherlands than that in India
3. Greater economic advancement of the Netherlands
4. More natural resources in the Netherlands.

Answer: 2. A Greater proportion of the inhabitable area is there in the Netherlands than that in India

Human Health And Disease Mcq For Neet

Question 7. The high population concentration of India is due to the:

1. The poor economic status of the people of the country
2. Availability of fertile land
3. Industrial advancement
4. Non-availability of resources.

Answer: 1. Poor economic status of the people of the country

Question 8. The very dense population of Indo-Gangetic plains is due to the:

1. Availability of adequate river water
2. Fertile alluvial soil of the region
3. Both of the above factors
4. Presence of large cities.

Answer: 3. Both of the above factors

Question 9. Some densely populated cities like Durgapur and Bhilai came up recently as a result of:

1. Removal of forests
2. Better transport facilities
3. Better agricultural opportunities
4. Development of resource-based industries.

Answer: 4. Development of resource-based industries.

Question 10. Most of the world’s largest cities are found at coastal locations primarily due to the:

1. Pleasant coastal climates
2. Availability of water
3. Availability of seafood
4. The fact that the sea provides a cheaper mode of transport.

Answer: 4. Fact that the sea provides a cheaper mode of transport.

Question 11. Demography is the study of:

1. Fossils and their distribution
2. Statistics of population
3. Relationship between man and the environment
4. None of the above.

Answer: 2. Statistics of population

Human Health And Disease Mcq For Neet

Question 12. The term biotic potential means:

1. Distribution of human population in an area
2. The rate of growth of population in an area
3. The physiological capacity of an organism to reproduce
4. The increase in number of human population in a country.

Answer: 3. The physiological capacity of an organism to reproduce

Question 13. The basic cause of continued urban growth is due to the:

1. Better transport facility
2. Entertainment facility
3. Prosperity in cities
4. Better health facilities.

Answer: 3. Prosperity in cities

Question 14. Increasing urbanization causes:

1. Overcrowding
2. Health and pollution hazards
3. Socio-economic problems
4. All the above.

Answer: 4. All the above.

Question 15. The biosphere consists of interaction ecological functional units called:

1. Ecosystems
2. Populations
3. Communities
4. Species.

Answer: 1. Ecosystems

Neet Mcqs On Human Health And Disease With Answers

Question 16. Agriculture and urbanization are two examples of man’s capacity to create new:

1. Species
2. Ecosystem
3. Biosphere
4. Lithosphere.

Answer: 2. Ecosystem

Question 17. The middle phase of the population growth curve is a phase of:

1. No growth
2. Low growth
3. Maximum growth
4. Stabilised growth.

Answer: 3. Maximum growth

Question 18. A population can grow exponentially:

1. When food is the only limiting resource
2. When first invading a suitable and previously unoccupied habitat
3. Only if there is no predation
4. Only in the laboratory.

Answer: 2. When first invading a suitable and previously unoccupied habitat

Question 19. Which of the following does not directly affect biotic potential?

1. A female’s age of first reproduction
2. Carrying capacity of the environment
3. Length of time a female is fertile
4. Average number of offspring per brood or litter.

Answer: 2. Carrying capacity of the environment

Human Health And Disease Class 12 Mcq

Question 20. The best way to decrease the population of a country is:

1. To educate the people
2. To have better living conditions
3. Mass killing
4. To practise and implement family planning techniques.

Answer: 4. To practise and implement family planning techniques.

Question 21. The main factors for the growth of the human population in India are:

1. High birth rate
2. Less death rate
3. Lack of education
4. All of the above.

Answer: 4. All of the above.

Question 22. The prenatal diagnostic technique is known as:

1. Implantation
2. Amniocentesis
3. Parthenogenesis
4. Biomedical termination of pregnancy.

Answer: 2. Amniocentesis

Question 23. At the current rate of growth, the human population is doubling itself every:

1. 50 yrs
2. 25 yrs
3. 40 yrs
4. 35 yrs.

Answer: 4. 35 yrs.

Question 24. The carrying capacity is represented by:

1. K
2. S
3. J
4. I.

Answer: 1. K

Question 25. What is the popular name of IVF?

1. Amniocentesis
2. Tubectomy
3. Rhythm method
4. Test tube baby.

Answer: 4. Test tube baby.

Human Health And Disease Class 12 Mcq

Question 26. The most thickly populated country in the world is:

1. Australia
2. India
3. Japan
4. The USA.

Answer: 3. Australia

Question 27. The most thinly populated country in the world is:

1. Australia
2. India
3. Japan
4. The USA.

Answer: 1. Australia

Question 28. The most thickly populated state of India is:

1. Orissa
2. Tamil Nadu
3. Punjab
4. Kerala.

Answer: 4. Kerala.

Question 29. The environmental resistance means:

1. The environmental factors which tend to maintain homeostasis by regulating emigration
2. Factors imposing a check on population size
3. Resistance of a species to the environmental factors which impose a check on population size
4. The physiological capacity of a species to resist changes in the environment.

Answer: 2. Factors imposing a check on population size

Question 30. Fertilisation of the ovum may be prevented by:

1. Tubal ligation
2. Vasectomy
3. Use of IUCD
4. All of the above.

Answer: 4. All of the above.

Question 31. Which is biologically responsible for the sex of the child?

1. Father
2. Mother
3. Both parents
4. God.

Answer: 1. Father

Common Human Diseases Mcqs For Neet

Question 32. A contraceptive pill contains:

1. Progesterone and estrogen
2. Spermicidal salts
3. Chemicals that cause abortion
4. Chemicals that prevent fertilization.

Answer: 1. Progesterone and estrogen

Question 33. According to the 1991 census, human population was:

1. 689 million
2. 840 million
3. 1032 million
4. 960 million.

Answer: 2. 840 million

Question 34. A contraceptive pill prevents ovulation by:

1. Blocking fallopian tubes
2. Inhibiting the release of FSH and LH
3. Stimulating release of FSH and LH
4. Causing immediate degeneration.

Answer: 2. Inhibiting release of FSH and LH

Question 35. Which mechanical device to control childbirth is fitted on the cervix?

1. Diaphragm
2. Condom
3. Loop
4. Copper T.

Answer: 1. Diaphragm

Question 36. Laparoscopy means:

1. Removal of ovary
2. Removal of a part of the oviduct
3. Tubular ligation
4. Fitting copper T.

Answer: 3. Tubular ligation

Question 37. Mothers nurse the foetus in the womb for:

1. 180 days
2. 210 days
3. 270 days
4. 320 days.

Answer: 3. 270 days

Question 38. According to the 1991 census, the urban population of India is about:

1. 30%
2. 24%
3. 57%
4. 34%.

Answer: 2. 24%

Common Human Diseases Mcqs For Neet

Question 39. At present world population is increasing at the rate of:

1. 2%
2. 2.25%
3. 2.50%
4. 30%.

Answer: 1. 2%

Question 40. The rapid decline in a population due to a high mortality rate is:

1. Population density
2. Population crash
3. Population explosion
4. All of the above.

Answer: 2. Population crash

Question 41. Growth of the population of an area depends upon:

1. Natality rate
2. Immigration
3. Environmental resistance
4. All of the above.

Answer: 4. All of the above.

Question 42. The physiological capacity of a species of animals to produce that progeny in the absence of natural enemies, disease or other inhibiting factors is:

1. Carrying capacity
2. Biotic potential
3. Population explosion
4. All of the above.

Answer: 2. Biotic potential

Question 43. The concept that “population tends to increase geometrically while food supply increases arithmetically” was put forward by:

1. Thomas Malthus
2. Adam Smith
3. Stuart Mill
4. Charles Darwin.

Answer: 1. Thomas Malthus

Question 44. In India, the human population is heavily weighted towards the younger age groups as a result of:

1. Short lifespan and low birth rate
2. Long life-span of many individuals and low birth rate
3. The short life span of many individuals
4. Long life span and low birth rate.

Answer: 3. Short life span of many individuals

Question 45. Which mechanical means is used to cover the penis before coital activity?

1. Diaphragm
2. Condom
3. Loop
4. Copper-T.

Answer: 2. Condom

Common Human Diseases Mcqs For Neet

Question 46. The best way to control the population is:

1. Education
2. Family planning
3. Better living conditions
4. Better health care.

Answer: 2. Family planning

Question 47. An IUCD is:

1. Copper-T
2. Condom
3. Vasectomy
4. Pill.

Answer: 1. Copper-T

Question 48. Surgical removal of the testes of males to control the population is:

1. Castration
2. Tubectomy
3. Laparoscopy
4. Vasectomy.

Answer: 1. Castration

Question 49. A permanent method of birth control is:

1. Vasectomy
2. Tubectomy
3. Both (1) and (2)
4. None of these.

Answer: 3. Both (1) and (2)

Question 50. Which mechanical device to control childbirth is fitted on the cervix?

1. Diaphragm
2. Condom
3. Loop
4. Cooper T.

Answer: 1. Diaphragm

Question 51. Saheli, a female antifertility pill is used:

1. Daily
2. Weekly
3. Quarterly
4. Monthly.

Answer: 2. Weekly

Question 52. Which of the following is a 100% effective method of birth control?

1. Use of oral contraceptives
2. Use of I.U.C. Devices
3. Use of condoms
4. Medical Termination of Pregnancy.

Answer: 1. Use of oral contraceptives

Question 53. In the past, to control population, the Family Planning Department has been advocating:

1. Ligation
2. Salpectomy
3. Vasectomy
4. All of the above.

Answer: 4. All of the above.

Question 54. Government-sponsored “Family Planning Programme” started in:

1. 1947
2. 1950
3. 1951
4. 1955.

Answer: 3. 1951

Question 55. Laparoscopy means:

1. Removal of ovary
2. Removal of a part of the oviduct
3. Tubular ligation
4. Fitting copper T.

Answer: 3. Tubular ligation

Question 56. The chemical method of birth control involves the use of:

1. Condom
2. Loop
3. Cream or jelly
4. Diaphragm.

Answer: 3. Cream or jelly

Human Health And Disease Mcq For Neet

Question 57. A contraceptive can be:

1. Condom, cervical cap or diaphragm
2. Intrauterine device
3. Pill
4. All the above.

Answer: 4. All the above.

Question 58. Which of the following is a mechanical device of birth control?

1. Copper-T
2. A combined pill
3. Foam tablet
4. Abortion pill.

Answer: 1. Copper-T

Question 59. Fertilisation of the ovum may be prevented by:

1. Tubal ligation
2. Vasectomy
3. Use of IUCD
4. All of these.

Answer: 4. All of these.

Question 60. A sterilization technique is:

1. Loop
2. Diaphragm
3. Tubectomy
4. Cervical cap.

Answer: 4. Cervical cap

Question 61. According to the 1991 census, the urban population of India was about:

1. 30%
2. 24%
3. 57%
4. 34%.

Answer: 2. 24%

NEET Questions Human Health and Diseases Question 62. In 1991, the Indian population was:

1. 832.93 million
2. 843.93 million
3. 840.90 million
4. 830.90 million.

Answer: 2. 843.93 million

Question 63. The 1991 census of population in India indicates:

1. Sudden fall in the birth rate
2. Minor fall in birth rate
3. No fall in birth rate
4. Increased birth rate.

Answer: 2. Minor fall in birth rate

Human Health And Disease Mcq For Neet

Question 64. In India, the marriageable age for females is:

1. 15 years
2. 18 years
3. 20 years
4. 21 years.

Answer: 2. 18 years

Question 65. Which of the following is involved in test-tube baby production?

1. Laparoscopy
2. Catheter
3. In-vitro fertilization
4. All of these.

Answer: 4. All of these.

Question 66. Amniocentesis can reveal the foetus’s:

1. Chromosomal abnormalities
2. Physical deformities
3. Metabolic disorders
4. Only (1) and (3).

Answer: 4. Only (1) and (3).

Question 67. In amniocentesis:

1. The foetal cells are taken out, cultured and examined for metabolic defects
2. The foetus is examined for metabolic defects
3. The foetus is examined for sex
4. The amniotic fluid is examined for metabolic defects.

Answer: 1. The foetus is examined for metabolic defects

Question 68. Which of the following is a pre-natal diagnostic technique?

1. X-ray technique
2. IUCD
3. Tubectomy
4. Amniocentesis.

Answer: 4. Amniocentesis.

Question 69. Test-tube baby is the one:

1. Who is reared on artificial medium outside the womb
2. Whose early growth is inside the female body but later growth on artificial medium
3. Whose fertilization and early growth are on an artificial medium but later implantation in the female uterus
4. Whose growth is inside the fallopian tube instead of the uterus.

Answer: 3. Whose fertilization and early growth is on an artificial medium but later implantation in the female uterus

Question 70. Pre-natal defects in the foetus can be detected by:

1. Laparoscopy
2. Amniocentesis
3. Genetic engineering
4. Sonography.

Answer: 2. Amniocentesis

Human Health And Common Human Diseases For NEET

Disease. It is defined as a condition of the body or a part of it in which functions are disturbed. The word disease means lack of ease and comfort.

Health. It is a state of complete physical, mental and social well-being. Health is also linked with social environment and cultural background.

Koch’s Postulate. Robert Koch (1876) studied diseases and pathogens of anthrax caused by Bacillus anthracite, later on, tuberculosis caused by Mycobacterium tuberculosis (1882) and cholera caused due to infection of Virbrio cholera (1883). He proposed the following four criteria for establishing an agent of infectious diseases.

The organism must be regularly found in the body of animals that have the disease.

1. It must be possible to isolate the organism and grow it in pure culture on artificial media.
2. A healthy animal must contract the disease and show its characteristic symptoms when it is inoculated with the culture of the organism.
3. It must be possible to recover the same organism from the body of an inoculated animal.

Human Health And Diseases Notes For Neet

Kinds Of Diseases

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1. Congenital Diseases. (Inborn diseases). Diseases contracted before birth due to defective heredity (chromosomal abnormalities and gene mutations), physiological disturbance or transplacental transmission for example, Haemophilia, Down’s syndrome, colour blindness, hare lip, and transplacental syphilis.
2. Acquired Diseases. Diseases contracted after birth due to infection, defective diet, hypersensitivity, injury, addition, degeneration, depression, etc.
3. Infectious Diseases. They are diseases due to pathogens that can be transferred from one individual to another for example, tetanus, measles, flu, malaria, typhoid, cholera, and tuberculosis.
4. Deficiency Diseases. Diseases caused by absence or deficiency of an essential element, for example, anaemia, goitre.
5. Degenerative Diseases. Diseases caused by ageing, result in malfunctioning or decreased efficiency.

Human Health And Common Human Diseases For NEET Disease Agents

Any substance which causes a disease by its excess deficiency or absence is called a disease agent.

Types of Disease Agents. Disease agents are of the following types:

1. Biological Agents. These are also called pathogens (Gr. path means disease; genes means producing). These are those micro-organisms which when successfully infect the human body, multiply and produce toxins in the incubation period which interfere with the normal functioning of the body and cause a disease.
   • These include viruses (mumps, chicken pox, smallpox),
     • Mycoplasma, (for example bronchitis, acute leukaemia),
     • Chlamydia (for example. trachoma)
     • Bacteria (for example, cholera, tetanus),
     • Fungi (ringworm, thrush, moniliasis, pulmonary aspergillosis),
     • Protozoa (for example, giardiasis, sleeping sickness),
     • Helminths (for example, filariasis, ascariasis, taeniasis), and
     • Other organisms (for example, scabies).
2. Chemical Agents. Some chemical compounds are also causative agents of certain diseases. These are of two types on the basis of their source.
   • Endogenous Chemical Agents. These are formed inside the body. These include urea, uric acid, hormones, enzymes etc.
   • Exogenous Chemical Agents. These enter the human body from outside by ingestion, inhalation or inoculation. These include pollutants like gases, dust, metals etc. and allergens like spores, pollens etc.
3. Nutritive Agents. These include minerals, carbohydrates, proteins, fats, vitamins and water.
4. Physical Agents. These include heat (stroke), cold (frostbite), humidity, pressure, radiation, electricity, sound (impaired hearing) etc.
5. Mechanical Agent. These include injuries, fractures, sprains, dislocations etc.
6. Genetic Agents. Some diseases are caused by genetic causes and include haemophilia, sickle cell anaemia, etc.
7. Degeneration. Due to old age.
8. Social Agents. These may cause mental disorders.
9. Unknown Reasons. The agents for certain diseases like peptic ulcers, hypertension and coronary heart diseases are yet to be identified.

Human Health And Common Human Diseases For NEET Modes Of Transmission

Communicable diseases are those diseases which can be transmitted from the reservoir of infection or an infected person to healthy but susceptible persons.

There are two modes of transmission:

1. Immediate Transmission Or Direct Transmission:

The pathogens are transmitted straight from an infected individual to a healthy individual without an intermediary agent. It manifests in the following manners:

1. Through direct contact with an infected individual: Contagious diseases such as chickenpox, smallpox, athlete’s foot, measles, leprosy, ringworm, gonorrhoea, and syphilis are transmitted through direct contact between an infected individual and a healthy individual. Entamoeba gingivalis, the oral amoeba, is transferred through direct mouth-to-mouth contact, such as kissing.
2. Droplet Transmission: Diseases such as diphtheria, influenza, the common cold, measles, TB, pneumonia, mumps, and whooping cough are transmitted through droplet infection, which involves pathogens contained in minute mucus droplets expelled during sneezing, coughing, spitting, or conversing with infected individuals.
3. Animal Bites: Rabies viruses are transmitted to humans by the bites of rabid animals such as dogs, monkeys, and cats.
4. Transplacental Transmission: The viruses responsible for German measles and the bacteria causing syphilis can be transferred from maternal blood to fetal blood via the placenta.

2. Indirect Transmission:

When infections are transmitted from the infection reservoir to a healthy individual via intermediary agents.

It manifests in the following manners:

1. Vector-borne: Vector-borne diseases include, for instance, the tsetse fly (African sleeping sickness) and sandflies (kala-azar and oriental sores). Female Anopheles mosquito (malaria), rat flea (bubonic plague), Aedes mosquito (yellow fever), Culex mosquito (filariasis), and housefly (typhoid, cholera, dysentery, etc.)
2. Pediculus humanus capitis (typhus) – Vehicle-borne: Pathogens responsible for cholera, dysentery, and typhoid are disseminated by vectors such as food and water. AIDS is transmitted through the blood of infected individuals.
3. Airborne: Pathogens are disseminated through wind currents, aerosol sprays, and dust, as exemplified by epidemic typhus.
4. Formite Borne: Pathogens are disseminated by contaminated items such as handkerchiefs, towels, dinnerware, toys, soap, cutlery, and surgical tools.
5. Imperfect Hands: The pathogens responsible for disorders such as Ascariasis (Ascaris lumbricoides) and Enterobiasis (Enterobius vermicularis) are transmitted by contaminated hands; therefore, thorough handwashing is essential before to meals.

Human Health And Common Human Diseases For NEET Defence Mechanism Of Body

External Defence/ First, Line Of Defence/Physical And Chemical Barrier. It consists of physical barriers of skin, membranes, friendly microorganisms and chemical barriers.

1. Skin. Keratinised dead outer epidermal cells do not allow entry to pathogens. Oil and sweat are inhibitory to the growth of most pathogens.
2. Nostril Hair. They Filter out dust and microorganisms from inhaled air.
3. External Friendly Microorganisms/Friendly Bacteria. Many friendly bacteria live on the skin and secrete chemicals harmful to pathogens.
4. Mucous Membranes. They line digestive, respiratory and urinogenital tracts so as to prevent the entry of germs into body parts.
5. Mucus And Cilia. The mucous membrane of the nasal tract possesses cilia for pushing back dust and germs. It also secretes mucus for trapping and killing them.
6. Internal Friendly Microorganisms. They occur in the intestine and vagina.
7. Chemical Barriers
   • Sweat, oil and secretions of extremely friendly bacteria are acidic to prevent the growth of many pathogens.
   • Lysozyme or bacteriolytic enzyme is present in sweat, tears, saliva and mucus.
   • Hl of the gastric juice has germicidal properties.
   • Bile does not allow the growth of microorganisms.

Non-Specific Internal Defence/Second Line Of Defence: A pathogen having entered body tissues/fluid is confronted with the second line of defence consisting of phagocytosis and inflammatory response.

1. Phagocytosis. Phagocytes present in the blood come out of the capillaries through diapedesis. Phagocytes of blood and macrophages present in tissues attack germs and engulf them. Pus may collect. Pus is a thick liquid formed in the region of the wound and is composed of tissue fluid, damaged body cells, dead phagocytes, some leucocytes and microorganisms.
2. Inflammatory Response. It is the reaction of living tissues to injury, irritation or infection which is characterised by pain, swelling, redness and heat. Inflammatory’ response can be localised (area of injury or infection) or systemic (whole body). It is caused by the release of an amine called histamine (C₅H₉N₃) from body tissues and lymphocytes.
   • Histamine dilates blood capillaries, makes them more permeable, lowers blood pressure, and allows greater leakage of phagocytes and plasma so that tissue fluid accumulates (histamine also stimulates gastric secretions and uterine contractions).
   • Toxins released by pathogens, and endogens pyrogens (Substances capable of producing fever/pyrexia) produced by leucocytes raise body temperature to stimulate phagocytes and inhibit microorganisms.
   • Pyrogens reset the thermoregulatory centres of the hypothalamus. However, body temperature may rise too high when it is brought down by the administration of antipyretic drugs (for example, paracetamol, and aspirin) and cold packs. Phagocytes attack vigorously when body temperature is high.

Specific Internal Defence Immune System/Third Line of Defence:

A constituent of a pathogen behaves as an antigen. Antigen (antibody generating) is any foreign substance like protein or polysaccharide present on the external coating of the pathogen, the toxin of the pathogen, white of egg, feathers, a constituent of a vegetable, fruit, meat, drug, chemical, tissue or organ transplant which induces the immune system to produce antibodies.

Human Health And Diseases Notes For Neet

Antibodies. Chemical substances are produced for the destruction of disease-producing external factors. Antibodies are made of complex proteins called immunoglobulins (Ig). They are of 5 types (IgM, IgG, IgA, IgD and IgE). Some important antibodies are tetanus antitoxin, agglutinins, bacteriolysis, oposonins etc.

Types Of Antibodies

Structure Of Antibody And Its Specificity: An antibody is a globular protein consisting of four polypeptide chains; two identical heavy chains, with more than 400 amino acids each, and two Identical light chains, with about 200 ammo acids each.

Along half the molecule, carbohydrate groups are attached and the two heavy chains are held closely together by a series of disulphide bonds. Along the other half, the chains are aligned in two pairs, with one heavy and one light chain in each pair. The entire molecule is shaped like a Y. Each antibody molecule has two functions:

1. An effector function or type of action taken to eliminate the antigen, and
2. A specific antigen-binding function.

There are five groups of mammalian antibodies, which are classified according to their effector function IgG, IgM, IgA, IgD, and IgE. (Ig stands for immunoglobin, the term for all proteins with antibody function.) IgG antibodies are the gamma globulins that circulate in the blood and attack both bacteria and viruses.

• Other groups attach to the plasma membranes of B cells, activate complement, enhance phagocytic activity, and play various other roles in fighting disease-causing microbes.
• The five groups are distinguished from one another by the amino acid sequences in their constant (C) regions, with all molecules in a group having the same sequence. Additionally, the attached carbohydrate groups help determine the particular effector function of the antibody.

There must be millions of different kinds of antibodies with regard to specific-binding capacity since one kind exists for almost every kind of foreign macromolecule. The specificity of an antibody for an antigen lies in its sequence of amino acids within the two “arms” of the molecule.

• These so-called variable (V) regions form the active sites, where the molecule binds to specific antigens. Both arms have the same amino acid sequence and so bind the same kind of antigen.
• Thus, each antibody can join two antigens, and many antibodies working together can clump, or agglutinate, more antigens for many efficient elimination by die different effectors.

Antimicrobial Substances. Antimicrobial biochemicals are also part of the non-specific immune response. Certain animal cells infected with viruses produce polypeptides called cytokines.

One type of cytokine, an interferon, diffuses to healthy neighbouring cells and stimulates them to produce biochemicals that block viral replication. When these cells become infected, the viruses are unable to take over the protein synthetic machinery to manufacture more of themselves. The spread of the infection halts.

Interferon. It is a protein produced by virus-infected cells. Interferon binds to receptors of non-infected cells, causing the cells to prepare for a possible attack by producing substances that interfere with viral replication. Interferon is specific to the species, therefore, only human interferon can be used in humans.

Human Health And Common Human Diseases For NEET Types Of Immune System

The immune system is of two types:

1. Humoral Or Antibody-Mediated Immune System (Amis). It is formed of proteinaceous defensive chemicals, called antibodies which are produced by B-Iymphocytes and circulate in the plasma of blood and lymph (humour = body fluids) and protect the body from bacteria and viruses that enter the blood and lymph. There are about 10²⁰(100 million trillion) antibody molecules.
2. Cell-Mcdialcd Immune System (CMIS). It is formed of highly specialized cells called T-Iymphocytcs which directly attack the pathogenic micro-organisms (like protozoans and fungi) that have entered the host’s body or grafts such as transplanted kidney or skin grafts taken from another person (allografts). It also protects the body from its own cells which have become cancerous.

How Do The Different Kinds Of T Cells Develop: The source of all blood cells, including white cells, is Lhc bone marrow. However, this tissue produces only stem cells —primitive, immature lymphocytes that migrate to other parts of the body for development into mature, functional cells. Most immature lymphocytes are formed during foetal life (prior to birth).

• About half the lymphocytes that leave the bone marrow pass through the thymus a mass of tissue located within the chest cavity just below the neck. The thymus is quite large during infancy but shrinks to a very small size in early childhood and remains small throughout life.
• Cells that pass through this organ before entering the circulatory system develop into T cells. They are especially effective in detecting and destroying eukaryotic cells with foreign antigens on their surfaces, such as those that have become cancerous and infected with viruses.
• The plasma membrane of a T cell contains receptor proteins that recognize one particular antigen. When the cells contact with this antigen, they differentiate into one of three types of T cells—cytotoxic, helper, or suppressor.
• Cytotoxic (or killer) T cells destroy their target cells by releasing a substance that dissolves holes in their plasma membrane, causing the target cell to lyse. Helper T cells stimulate B cells to make antibodies and facilitate the action of other T cells.
• Some helper cells secrete lymphokines or interleukins, which are messenger molecules that recruit other white blood cells to the battle site. Suppressor T cells cause both B cells and other T cells to become less active.

Action Of T Cells: When triggered off by antigens, T-cells also produce a clone of T-cells such as

1. Killer T-cells or KT Cells—Directly attack and destroy antigens.
2. Helper T-cells or HT cells—Stimulate B-cells to produce more antibodies.
3. Suppressor T-cells or ST-cells—Check on entire immune system to attack the own body cells. Some of these cells become memory cells.

Memory T-cells. They are sensitised T-cells which retain the memory of antigen-specificity for the future, sometimes lifelong. Killer, helper and suppressor T-cells are also called effector cells.

Action Of B-Cells: The antigen-specific helper T-cells stimulate specific B-lymphocytes to multiply rapidly forming clones of plasma cells. In the presence of antigens, the plasma cells form antibodies at the rate of 2000 molecules per cell per second, a total of some 20 trillion per day.

Distribution Of B-And T-Cells In Human Body

Antibody Action (Effector Mechanism),

1. Neutralisation. Some antibodies function as antitoxins and neutralise the toxins produced by pathogens/foreign chemicals.
2. Agglutination. Antibodies called Agglutinins cause immobilisation and clumping of antigens (precipitation) and antigen-containing pathogens.
3. Opsonisation/Adherence. Antibodies called opsonins (for example, IgG) attach themselves to the surface of antigen-containing cells so as to be recognised by phagocytes,
4. Complement Mediated Cell Lysis. Antigen-containing cells are perforated by enzymes produced with the help of lysin antibodies (IgM IgG).
5. Phagocytosis. The lysed immobilised clumped pathogens are engulfed by killer T-cells and other phagocytes.

Principles Cells Of The Immune System

Immunity: After being stimulated B-cells and T-cells produce numerous effector cells and memory cells. Effector cells help in killing effective antigens and they live for a few days. The memory cells kill the antigens of the second infection and they live for much longer time and some may live even for the whole life.

These memory cells are stored in the spleen and lymph nodes. This explains the reason why some childhood diseases are not contracted for a second time. This is called acquired or active immunity. Immunity is of two types.

1. Innate immunity—Inborn.
2. Acquired immunity—Acquired after birth.
   1. Active acquired immunity
   2. Passive acquired immunity

Role Of Lymphoid Organs: The organs where lymphocytes are formed and mature, termed lymphoid organs. They are of two types i.e. Primary lymphoid organs and secondary lymphoid organs. Primary lymphoid organs such as hone marrow and thymus are the sites where B and T-cells can be produced.

• Secondary lymphoid organs such as lymph nodes, spleen, and mucosa-associated lymphoid tissue such as tonsils are the sites where lymphocytes are stored. They multiply and undergo differentiation at these sites.
• They acquire an immune response to antigens develop in their organs.

Human Health And Diseases Notes For Neet

Innate Or Inborn or- Non-specific or Natural Immunity:

It is present from birth and is inherited from the mother to offspring through the placenta. It is not acquired from the previous attack of disease, for example, innate immunity against distemper (a fatal disease of dogs) and cholera. It is the first line of defence. It consists of four types of barriers

1. Anatomical
2. Physiological
3. Phagocytic and
4. Inflammatory barriers.

Besides that phagocytes kill bacterial cells, virus-infected cells and some foreign cells of the body by creating perforin-lined pores in the plasma membrane of target cells. These pores allow entry of water into the target cell which then swells and bursts.

Acquired Immunity. The immunity acquired during a lifetime is called acquired immunity. It is specific and also known as adaptive immunity.lt requires many days to be activated. It has four unique properties

1. Specificity
2. Diversity
3. Memory and
4. Discrimination between self and non-self.

Specific Immunity employs two major groups of cells

1. Lymphocytes and
2. The antigen-presenting cells.

Properties Of Acquired Immunity

1. Specificity. It is able to recognize various foreign molecules.
2. Diversity. It can recognize a vast variety of foreign (non-self) molecules.
3. Memory. The immune system responds to first encountered by forming antibodies. It retains the memory and if there is a second attack by the same antigen, (microbe/foreign molecules) evokes a heightened immune response.
4. Distinguish Between Self And Non-Self Molecules. It can recognise and respond to molecules that are foreign or non-self

Activation Of Adaptive Immunity:

Every antigen is scanned by antigen-presenting cells like macrophages, B lymphocytes, etc. The processed antigen is present on the surface of these cells. A subgroup of T- T-cells, called T helper cells, specifically interacts with the present antigen and becomes activated.

The activated T helper cells then activate B cells and a subgroup of T cells called T cytotoxic cells in a specific manner. The activated B and T cytotoxic cells divide repeatedly to produce clones (similar cells). All the cells of a clone recognize the same antigen and fight it, neutralize the action or eliminate it.

Vaccination: Originally the term vaccination (alter the Latin word vacca = cow) is described as the process of inoculating persons with discharge from cowpox to protect them from smallpox.

But now it is applied to the inoculation of any antigenic material for the purpose of producing active artificial immunity. The first successful polio vaccine (the Salk vaccine) was composed of viruses that had been inactivated by treatment will) formaldehyde.

Kinds Of Vaccine

1. Killed Vaccine.
   1. The organisms are killed by phenol, alcohol, heat and UV rays, for example, Typhoid.
   2. Vaccine is prepared by killing organisms with the use of formalin, for example, whooping cough, and poliomyelitis (discovered by Salk).
2. Toxoid. They have lost their toxic property but retained antigenic properties, for example, antitetanus, and diphtheria toxoids.
3. Attenuated Living Vaccine. Oral ‘Live’ Sabine vaccine (OPV), Antipoliomyelitis (Salk); Antimeasles, B.C.G., yellow fever.
4. Antigens Isolated From Infectious Agents, for example, polysaccharides of pneumococci.
5. Antiserum/Serum. It is fibrinogen-free serum or blood plasma of an animal which has antibodies or antitoxins against a particular pathogen/toxin because the animal has been injected with a safe dose of the pathogen at regular intervals, for example, diphtheria, tetanus, or snake bite.
6. Monoclonal Antibodies (Magic Bullets). They are identical antibody molecules, specific for a particular antigen, which have developed from a single source like hybridoma.

They were devised by Cesar Milstein and George Kohler (1975). Hybrid cell culture formed of antigen-sensitised cells, fused with myeloma/cancerous bone marrow cells for indefinite production of monoclonal antibodies.

Passive Immunity: Passive immunity is short-lived. Passive immunity occurs when an individual is given prepared antibodies and immunoglobulins to combat a disease. Since these antibodies are not produced by the individual’s B cells, passive immunity is short-lived.

• For example, newborn infants are passively immune to diseases because antibodies have crossed the placenta from the mother’s blood.
• These antibodies soon disappear, however, so that within a few months, infants become more susceptible to infections. Breastfeeding prolongs the natural passive immunity an infant receives from the mother because antibodies are present in the mother’s milk.
• Even though passive immunity does not last, it sometimes is used to prevent illness in a patient who has been unexpectedly exposed to an infectious disease.
• Usually, the patient receives a gamma globulin injection (serum that contains antibodies), perhaps taken from individuals who have recovered from the illness.
• In the past, horses were immunized, and serum was taken from them to provide the needed antibodies against such diseases as diphtheria, botulism and tetanus.

Interferon: Interferon was first identified in 1957. These are proteins released by cells in response to a viral infection which they help to combat. They do not inactivate the virus but make the healthy cells less susceptible to the viral attack and prevent the viruses from taking over the machinery of the cells. Interferons have proved to be effective in treating influenza and hepatitis.

Common Human Diseases Neet Notes Pdf

Antisera

• Prior to the development of vaccinations, serum with preformed antibodies was utilized.
• This serum is referred to as Antiserum or hyperimmune serum.
• When utilized for protection, it is referred to as prophylactic serum.
• When utilized for therapeutic purposes, it is referred to as therapeutic serum, generally known as Gammaglobulin.
• It is derived from human blood sera provided by donors and contains antibodies.
• In certain instances, the body identifies these serum antibodies and antigens, subsequently generating antibodies against them in an allergic response. This condition is referred to as serum sickness.
• It leads to rash, respiratory distress, and joint swelling.

Human Health And Common Human Diseases For NEET Autoimmunity

The immunity developed against one’s own structure is known as autoimmunity. It has been observed that sometimes the immune system of the body goes off track and starts working against the own body and this in turn leads towards disease for example immunity developed against RBCs causes Anaemia and autoimmunity against the muscular system causes severe wsafeness (myasthenia gravis).

Human Health And Common Human Diseases For NEET Immunodeficiency

It is a disorder of the immune system where one or both components are unable to work properly due to congenital or acquired disease.

• SCID (Severe Combined Immunodeficiency): It is a congenital immunodeficiency disorder in which both B—and T—lymphocytes are not formed and the patient dies of even minor infection (Such children can survive only in germ-free isolation chambers).
• Acquired Immuno-Deficiencv Syndrome (AIDS) Cause. AIDS is a severe viral disease which has been able to overcome all the defensive mechanisms of the human body and generally leads to death.

It is caused by a retrovirus-HIV (Human immunodeficiency virus), earlier called LAV (Lymphadenopathy-associated virus) or HTLV (Human T-lymphotropic virus). It was first reported in African green monkeys but was first isolated in man by Moulagnier et al. (1983) and Gallo et.al. (1984). Its genetic material is RNA so it multiplies through the process of reverse transcription. Another peculiar feature of HIV is its mutability.

HIV– Human Immunodeficiency Virus

Subgroup- Lentivirus

Family– Retroviridae

Incubation Period, It ranges between 15-57 months. The average incubation period is 8 months.

Sites From Which HIV Can Be Isolated.

1. Blood
2. Semen
3. Cervical fluid
4. Saliva
5. Breastmilk
6. CSF
7. Tears
8. Skin
9. Lungs
10. Glial cells, Microglia of CNS.

AIDS Is a Pandemic Disease Symptoms. HIV attacks Helper T- lymphocytes. The reduction in number of Helper T-lymphocytes causes severe cellular immunodeficiency. The number of T-cells drops to even below 200 in comparison to 500-1500 in a normal person.

So it is a disorder of the cell-mediated immune system of the body. These clinically unhealthy persons are called opportunistic. AIDS is characterized by one of the following symptoms:

1. Pneumocystis Carinii Pneumonia (PCP) is a lung disease. Idiopathic multiple-a skin cancer (Kaposi’s sarcoma) These forms 70% of AIDS cases.
2. Psychosis Or Chronic Encephalitis– severe brain damage.
3. Thrombocytopenic Purpura– decreased count of blood platelets causing haemorrhage.
4. Lymphoma – cancer of lymphatics.
5. Lymphadenopathy- swelling of lymph nodes.
6. Another peculiar symptom of AIDS is severe wasting syndrome (substantial weight loss and general decline in health).
7. AIDS patients also become more susceptible to infections of any system of the body.
8. When the brain is damaged, then it may cause loss of memory, and the ability to speak and even think.

A full-blown AIDS patient dies within three years and mortality is 100%. The most serious form of AIDS is AIDS-related complex ARC which is characterized by swollen lymph nodes, night sweats and loss of weight.

New Anti-Retrovirus Drugs Against HIV

1. Protease Inhibitors in combination with AZT blocks the enzyme essential for multiplication of HIV-virus.
2. Sustiva, also called Efavienz, was developed by Food and Drug Administration (FDA) of USA in September, 1998.
3. XQ- 9302, a Chinese herbal medicine.
4. Interleukins (a class of proteins secreted by immune cells) when given in combination with AZT and protease inhibitors can remove the virus even from CD- 4 cells where the virus hides and rests.
5. Nono Xynol- 9, a spermicide in gel form and claimed to be anti- HIV is found to be ineffective in protecting women from HIV- Infection.
6. Nevirapine pervents HIV transmission from mother to child.

Two Serological Tests For Anti-HTV Antibodies

1. Screening Test.
2. Confirmatory Test.

1. Screening Test. These tests are not highly specific. The most widely used screening test is the ELISA test.
2. Confirmatory Test. A commonly employed confirmatory test is the Western Blot test. It is carried out after the screening test shows a positive result.

Immunosuppressants: They are chemicals which suppress the immune reaction of the body towards transplanted organs (for example, kidney, parts of the intestine, heart) for example, cyclosporin.

Infectious Diseases—some of them fatal, have newly emerged and were not previously known:

1. HIV infection which causes AIDS
2. Hepatitis C, B and E
3. A new form of Cholera
4. A highly fatal respiratory disease caused by a virus called Sin Nombre
5. A variant of Creutzfedt-Jakob disease—a disease of the central nervous system
6. Ebola haemorrhagic fever
7. A haemolytic uraemia syndrome

Reemerging Infectious Diseases: Some of the infectious diseases which were earlier controlled are now reappearing in epidemic forms. They are

1. Tuberculosis
2. Cholera
3. Dengue
4. Malaria
5. Plague
6. Meningococcal meningitis
7. Diphtheria
8. Japanese encephalitis

Diseases Caused By Bacteria

Other Bacterial Diseases Are diarrhoeal diseases (Shigella, Escherichia coli, Campylobacter, Salmonella etc.), botulism (food poisoning – Clostridium botulinum); anthrax (Bacillus anthracis); meningitis (Neisseria meningitis) etc.

Human Diseases And Their Causes Neet Biology

Diseases Caused By Viruses

Dengue Fever. It is a viral fever whose vector is a daytime-biting Aetles aepypti mosquito. Its incubation period is of seven days.

• It is characterized by high fever (above 102° F), severe frontal headache, pain behind the eyes, muscular and joint pain, loss of appetite, measles-like rash on the chest and upper limbs, nausea, vomiting etc.
• Dengue haemorrhagic fever is also associated with bleeding from the nose, mouth, and gums and vomiting. In October 1996, Dengue fever was declared as an epidemic.
• Adult Aetles mosquitoes can be killed by spraying malathion. Aedes mosquito has small, black and white strips on its legs and back. It bites during the daytime in the early hours of the morning and late hours of the afternoon.

The hepatitis -B Virus causes so many deaths in only one day as by AIDS virus in one year. In India, about 4.30 crore people suffer from hepatitis- B. The vaccine against hepa- titis-B is available and is given to the 6th, 10th and 14th years age group of children.

Revac-B vaccine is a genetically engineered vaccine against hepatitis-B disease. It has been developed by Bharat Biotech International Ltd. (Hyderabad).

SARS (Severe Agile Respiratory Syndrome): Typical pneumonia is an infection of lung tissue caused by organisms other than pneu¬monia causing organisms, maybe a virus, metapneumo virus another virus called corona vims has also been identified.

• Symptoms And Signs Of SARS
  • High fever
  • One or more respiratory symptoms (Cough, breathlessness or hypoxia.)
  • Headache, muscular stiffness, loss of appetite vague feeling of discomfort, confusion, rash and diarrhoea
  • Close contact with a person having SARS for the previous 10 days.
• Countries Which reported SARS cases: China. Hongkong, Taiwan province, Singapur, Vietnam and Canada In India only 12 cases of SARS were reported.
• Modes Of Transmission Droplet infection spread through respiratory surface Diagnostic Test. Rapid molecular Genetic Test ( PCR Test) 2. Serological Test. Treatment. Combination of Antiviral drugs and cortical steroids plus other intensive supportive treatment.

Protozoanal Diseases: Malaria, amoebiasis, sleeping sickness etc are the main protozoan diseases caused by Plasmodium, Entamoeba and Trypanosoma respectively. Malaria is spread by the female Anopheles mosquitoes, amoebiasis is spread by contaminated food and water, and sleeping sickness is spread by Glossina (Tse-tse fly).

Helminth Diseases: Tueniasis, ascariasis and filariasis are common helminth diseases of man. These are caused by Taenia solium, Ascaris lumbricoides and Wuchereria bancrofii respectively. Human infection of Taenia occurs by taking undercooked measly pork while that of Ascaris occurs through contaminated food. Filariasis is spread through Culcx and Aedes mosquitoes.

Important STDs And Common Techniques For Their Detection

Heart Diseases: These are the most common cause of death in human beings in the present century. Rheumatic heart diseases result from the repeated attacks of rheumatic fever in childhood.

• The toxins cause inefficiency of the valves between the auricle and the anti-ventricle. Arteriosclerosis is another common cardiovascular disease caused by the deposition of calcium or cholesterol in the walls of the arteries. Hypertension is characterized by persistent high blood pressure.
• Coronary thrombosis, also called myocardial infarction, involves the formation of a thrombus in the coronary artery. High sperm cholesterol, cigarette smoking, hypertension, diabetes and obesity are other risk factors for coronary heart disease.

Diabetes Mellitus

Diabetes Mellitus Causes

• Deficiency of insulin hormone due to hypoactivity of p—p-cells of Islets of Langerhans of the pancreas.
• Obesity and overweightness.
• Mental shocks.
• Heredity (diabetes controlled by a recessive gene present on the short arm of chromosome 11).

Diabetes Mellitus Symptoms. Due to a deficiency of insulin hormone, the person can neither store glucose as glycogen nor use glucose as respiratory fuel, so diabetes mellitus is characterized by:

Human Health And Diseases Neet Previous Year Questions With Answers

Hyperglycemia (blood glucose many times greater than normal), polyuria or diuresis (excessive urination, about 10 litres per day), polydipsia (excessive thirst), polyphagia (increased hunger), glycosuria (sugar in urine, about 100 g/24 hrs), loss of weight, decreased glycogen level in liver, blurred vision, reduced healing capacity etc. Due to incomplete oxidation of fats, ketonic bodies are formed, so secondary symptoms of diabetes mellitus are:

Ketonemia (ketones in the blood), Ketonuria (ketones in urine), acidosis (pH of blood decreased from 7.4 to 6.8), diabetic coma and death.

• A person suffering from diabetes is called a diabetic. It is reported in about 1-3% of Indian population. China now has 20 million diabetics and their number is swelling each year by 750,000. About 5.3 per cent of the inhabitants of Beijing city suffer from diabetes.
• So Beijing is becoming the city of diabetics. There are over 15 million known diabetics in India with Delhi alone accounting for over 3 lakhs. Increasing urbanization and a changing lifestyle with less physical exercise and overeating are responsible for the increase.

27th June is called Diabetes Day: Diabetes occurs in two forms

1. Insulin-dependant Diabetes (IDDM—Type-1 diabetes). It occurs due to a deficiency of insulin from (β cells of Islets of Langerhans. It is more severe and generally occurs in young.
2. Non-insulin-Dependent Diabetes (NIDDM—Type-2). It occurs due to the failure of the target cells to take up insulin from the blood. It generally affects after 40 years of age. Patients are mostly overweight so should reduce their weight by a low-calorie diet and exercise.

Diagnosis. Diabetes mellitus can be diagnosed by testing blood and urine sugar levels.

Diabetes Insipidus

Diabetes Insipidus Cause. The main cause of diabetes insipidus is decreased secretion of ADH (anti-diuretic hormone), also called vasopressin, from the neurosecretory cells of the hypothalamus and released from the posterior lobe of the pituitary gland.

Diabetes Insipidus Symptoms. Deficiency of ADH causes decreased permeability of the wall of collecting tubules and decreased reabsorption of water from the urine, so diabetes insipidus is characterized by:

Diuresis, polydipsia, loss of weight, weakness etc. but urine is sugar free.

Arthritis: It is a disease more of advanced age characterised by the abnormality of joints. The common three types of arthritis are :

1. Degenerative Arthritis (Osteoarthritis). It first attacks the cartilage of the joint. The lumps are formed which make the movement impossible. It causes joint fixation or ankylosis.
2. Rheumatoid Arthritis. It first attacks the synovial membrane (membrane which lines the joints) and causes inflammation which leads to stiffness of the joints.
3. Gout. It is a type of arthritis in which the accumulation of uric acid crystals occurs at the joints. These crystals make movement difficult and also cause severe pain.

Human Health And Common Human Diseases For NEET Allergies

Allergies Definition. An allergy is the hypersensitivity of a person to some foreign substance, called an allergen, which either comes in contact with or enters the body. About 15% of the Indian population suffers from one or other type of allergic disorder.

• Allergy, also known as hypersensitivity, is an inappropriate overreaction of the immune system.
• An allergy is a non-infectious, unnatural and unusual reaction to a substance called an allergen which is generally a weak antigen.
• Common allergies are anaphylaxis, urticaria, hay fever, asthma, eczema, etc.
• Antibodies belonging to the class IgE trigger allergy by combining with the antigen and surface of mast cells in the connective tissue.
• Mast cells release a large amount of histamine into the bloodstream.
• The symptoms of an allergy reaction develop in response to histamine which stimulates capillary dilation, increased permeability, closure of bronchial tubes, mucus secretion, pain and swelling.
• A severe allergic reaction called anaphylactic shock occurs when a large amount of histamine is suddenly) released by the mast cells.
• All the peripheral arteries dilate at once causing a very low blood pressure or shock. It is fatal if not immediately treated.
• Allergies are treated with drugs that cause vasoconstriction: antihistamines in the case of normal allergic reaction and epinephrine in the case of anaphylactic shock.

Human Health And Common Human Diseases For NEET Inflammation

Inflammation Definition. Damage to the body’s tissues triggers a defensive response called inflammation.

• Inflammation can be caused by microbial infection, or physical agents (heat, radiant energy, electricity or sharp objects).
• Inflammation is usually characterized by four symptoms.
  1. Redness
  2. Swelling.
  3. Heat
  4. Pain
• Sometimes a fifth symptom, loss of function, is present,
• Inflammation has the following functions:
• To destroy the injurious agent to limit the effects of the injurious agent on the body by confining or walling off
• To repair or replace tissue damaged by the injurious agent
• Any substance or agent that tends to cause a rise in the body temperature (fever) is called pyrogen.
• Pyrogens are released by WBCs that set the body’s thermostat at high temperatures.

Type Of Allergens. The common allergens are dust, pollens, spores, feathers, fur, venom food and drugs. Some physical agents also act as allergens.

Allergens Mechanism. It involves 3 steps:

1. Sensitisation. In this, allergen acts as a mild antigen so stimulates the formation of antibodies which bind to mast cells of connective fissure.
2. Second Stimulation. In this, allergens combine with antibody-bound mast cells which rupture and release histamine.
3. Histamine Action causes hypersensation.

Human Health And Diseases Neet Previous Year Questions With Answers

Symptoms Of Allergic Reactions. The following are the symptoms of allergies

• A person may suffer from high fever which affects the mucous membrane of the eyes, nose and upper respiratory tracts.
• The mucous membrane of the lower part of the respiratory tract leads to cough and asthma.
• Reddening of skin, the appearance of blisters on the skin.
• Accumulation of tissue fluid below the skin.
• Watering of eyes and inability to breathe.

Human Health And Common Human Diseases For NEET Cancer

Cancer is characterized by uncontrolled growth and division of certain body tissues, so forming a tumour. It is more common in people between 40 to 60 years of age. It is one of the chief killers today. Every year about 6 million people throughout the world are diagnosed as having cancer, being equally divided between developed and developing countries.

• In the world, about 4 million people die of cancer which accounts for about 10% of all deaths. In India, 80 per cent of cancer patients come from viral areas and are first diagnosed with cancer at an advanced stage.
• Neoplasm is a new abnormal tissue that is capable of continued growth, formation of tumours, crowding and disruption of normal cells. Tumours are of two types, benign and malignant. A benign tumour is a large localised mass of abnormal tissue which presses other tissues but does not infiltrate adjacent tissues because it is encapsulated in connective tissue.
• A Malignant Tumour is a large mass of abnormal tissue which is not encapsulated, is capable of invading adjacent tissue and distant sites. Metastasis is the spread of cancerous cells from one part of the body to other parts through blood, lymph or the formation of secondaries from a malignant tumour.

Cancers Are Of the Following Types:

1. Carcinoma:

It is a carcinoma of epithelial or epidermal tissues and its derivatives, including skin, mucous membranes, glands, lungs, breasts, pancreas, and stomach.

2. Sarcoma:

It is a malignancy of primordial mesodermal tissue, including connective tissue, bone, muscle, and lymph nodes.

3. Kaposi:

Kaposi sarcoma is a secondary condition linked to AIDS. Leukemia (= Leukemia). It is a malignancy characterized by an excessive and uncontrolled proliferation of white blood cells (200,000—1,000,000/mm³) and immature myeloid stem cells.

In a prevalent form of leukaemia, white blood cells invade the bone marrow, spleen, liver, lymph nodes, and other organs, resulting in damage and enlargement.

In myelocytic leukaemia, the 9th and 22nd chromosomes amalgamate their transposable elements, resulting in the degeneration of erythroblastic tissue in the bone marrow.

Hemorrhaging is occurring at several locations. Tonsils and cervical lymph nodes hypertrophy. The predominant cancers in India are oral-pharyngeal cancer in males and cervical-uterine cancer in females.

4. Adenoma: Glandular carcinoma

5. Lymphoma:

It is a malignancy of the lymphatic system and spleen, characterized by the overproduction of lymphocytes.

Carcinogenic Factors (Factors inducing Cancer).

Carcinogens/Chemical Carcinogens. They are substances/often environmental pollutants which cause cancer, for example, soot (skin, lungs). coal tar (3, 4, benzopyrene—skin and lungs), cigarette smoke (N-nitroso- dimethyl—lungs), cadmium oxide (prostate gland), aflatoxin (liver), 2-naphthyl amine and 4-aminobiphenyI (urinary bladder), mustard gas (lungs), nickel and chromium compounds (lungs), asbestos (lungs, pleural membrane), diethylstilbestrol (DES—vagina), vinyl chloride (liver).

• Radiations. Both UV and ionising radiation increase the incidence of cancer. For example, Leukaemia incidence is 10 times higher in radiologists than other medical workers.
• Heat. Reverse smoking causes mouth cancer. Kangri (heating device) increases the incidence of cancer in Kashmiris.
• Tobacco. Tobacco chewing produces mouth cancer. Smoking increases the chances of throat and lung cancers.

Biological Agents. Some viruses and other parasites, excessive secretion of certain hormones are believed to produce cancers.

Mechanical Agents. Friction, trauma or continuous irritation seem to produce cancer.

Mechanical Agents Symptoms. A lump or hard area, swelling or sore that does not heal, unexplained loss of weight, difficulty in swallowing, persistent cough or hoarseness, change in colour of a mole/wart, a change in digestive/bowel habits, loss of blood through a natural orifice or excess out of date loss of blood in women.

Therapy: Cancer can be controlled in early stages and control depends upon the location and spread of the cancer

1. Radiation Therapy. In this, the cancerous parts of the body are exposed to ionising radiation like X-rays which kill the cancerous cells. It gives good results in skin, lip, mouth and cervix cancers.

It is used in almost 80% of cancer patients for treatment Brachytherapy is a special radiotherapeutic technique in which a very high doze of radiation in a short period to a small volume of body tissue by small radioactive sources like Radium, Cobalt 60, Iridium-192, etc. arranged in a geometrical fashion in and around the tumour.

2. Hormonal Therapy. In this, a hormone-caused cancer is treated by another hormone which neutralizes carcinogenic hormones for example, breast cancer can be controlled by testosterone.

3. Surgery. It involves the removal of cancerous parts by operative methods.

4. Chemotherapy. A number of chemicals like mercaptopurine, 6-aminopterin etc. are known to kill cancerous cells or inhibit DNA synthesis and cell division in cancer cells. Catharantlius roseus, commonly called sadabahar, provides two anti-cancerous drugs; Vincristin and Vinblastin which are used against leukaemia.

A new drug called Photoferin has been discovered in the U.S.A. to cure throat cancer. It is a modified porfimer sodium extracted from cow’s blood.

Drugs Used In Chemotherapy Of Cancer

5. New Anti-Cancer Drugs. The new drug, Doxil, contains an antitumour ingredient called Doxorubicin.

• Recently Israeli researchers have developed a new technique of new dmg delivery in which liposomes (a group of ball-like biomaterials) infiltrate the malignant tumours through the gaps in the blood vessels of cancerous tissue and release the anticancerous doxil to kill the cancerous cells.
• These liposomes cannot penetrate into healthy tissue as no such gaps exist in their blood vessels.

6. Gene Therapy For Skin Cancer. A revolutionary form of gene therapy for skin cancer has been developed by Mary Collins of the Institute of Cancer Research (London). In this, tumour cells are genetically engineered to carry a protein—Interleukin-2.

Then the tumour cells are injected into the skin of the patient where they begin to release Interleukin- 2 which stimulates the white blood cells to attack cancer cells in the skin, hopefully preventing cancer from spreading.

Therapy Mechanism: Carcinogenic factors activate certain genes called oncogenes. Jumping genes or transposons are also involved. The activated oncogenes result in uncontrolled cell proliferation or cancer.

Cancer cells have irregular, hypertrophied nuclei, abundant nuclear granules, an increased number of lysosomes, reduced cristae in mitochondria, melanin, mucus, fat droplets and debris in cells.

ABO Blood Group:

Whether a person has type A, type B, type AB or type O blood depends on the presence or absence of specific substances on the red blood cells. There are two of these substances- antigens A and B.

• Thus a person with antigen A is considered to be with blood group A, a person who is in blood group O has neither of the antigens and a person with antigen B, blood group is called B. If both the antigens A and B are present the blood group is called AB. The blood group character is controlled by a set of three alleles.
• During injury or disease blood is lost and is generally replaced by transfusion. The blood is obtained from a donor and must be compatible with that of the person receiving, i. e.. recipient.
• In case the blood is not compatible then the antibodies present in them cause clumping of blood in the capillaries and may result in death. The plasma of B-group blood contains antibodies A. The formation of clumps occurs in case B group blood is mixed with blood group A.

Human Health And Diseases Neet Previous Year Questions With Answers

Rh Factor. The Rh-blood types were first discovered in the Rhesus monkey. It was found that RH (rhesus) antigens were causing many of the transfusion failures that were unexplained by the A-B-O system. There are at least eight different Rh antigens discovered so far. A person is called Rh- Rh-Rh-positive if he has any one of these antigens and Rh-negative if the antigens are absent.

• A complication arises if the blood of an Rh-negative is transferred to Rh- a positive individual or vice-versa.
• When the red blood cells of an Rh-positive person is transfused into a person with Rh-negative blood an agglutination of red cells occurs. The antibodies against the Rh antigen are present in the Rh- Rh-negative person. The agglutinated cells clog up capillaries and the white cells of the recipient attack and break up the red blood cells (hemolysis).
• Repeated exposure to transfusion increases the speed and seriousness of the antibody-antigens response. In such cases, serious complications arise which lead to death.

NEET Biology Human Health And  Common Human Diseases Multiple Choice Questions And Answers

Question 1. Common examples of allergens are mites in dust, pollens, and animal dander. Allergy is due to the release of chemicals such as:

1. IgF
2. Histamine
3. Colostrum
4. Histamine and serotonin

Answer: 4. Histamine and serotonin

Question 2. Which of the following is an autoimmune disease?

1. Gout
2. Rheumatoid arthritis
3. Diabetes inspires
4. SCID.

Answer: 2. Rheumatoid arthritis

Question 3. BCG vaccine is given against:

1. Typhoid
2. Cholera
3. TB
4. Diphtheria.

Answer: 3. Diphtheria.

Question 4. Which of the following is a symptom(s) of ascariasis?

1. Muscular pain and fever
2. Internal bleeding and anaemia
3. Blockage of intestinal passage
4. All the above.

Answer: 4. All the above.

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Question 5. The appearance of dry, scaly lesions on various parts of the body such as skin, nails and scalp accompanied by intense itching. This disease is caused by:

1. Epidermophyton
2. Microsporum
3. Trichophyton
4. All the above.

Answer: 4. All the above.

Human Health and Disease MCQs with Answers Question 6. Elephantiasis or filariasis is caused by Wuchereria bancrofti and W. malayi. The major symptoms are

1. Chronic inflammation of lymphatic vessels of lower limbs
2. Deformities of genital organs
3. Swelling of scrotum
4. All the above.

Answer: 4. All the above.

Human Health And Disease Mcq For Neet

Question 7. Sporozoites of malarial parasite on entering the blood first attack:

1. RBCs
2. Liver cells
3. Blood platelets
4. WBCs

Answer: 2. Liver cells

Question 8. Who is the initiator of the ‘Lab to Land’ concept?

1. M.S. Swaminathan
2. Norman Borlaug
3. G.S. Khush
4. G.S. Randhawa.

Answer: 1. M.S. Swaminathan

Question 9. In pneumonia, symptoms include fever, cough, chills, and headache, and lips and fingers may turn grey to blue colour. It is caused by

1. Streptococcus pneumonia
2. Haemophilus influenza
3. Aedes
4. Both (1) and (2).

Answer: 4. Both (1) and (2).

Question 10. The proteins produced by B-lymphocytes in response to pathogens are called

1. Antigens
2. Interferons
3. Antibodies
4. PMNL.

Answer: 3. PMNL.

Question 11. Japenese elephantiasis is transmitted by:

1. Housefly
2. Tse-tse fly
3. Phlebotomus
4. Mosquito.

Answer: 4. Mosquito

Question 12. Select the correct statement:

1. Barbiturates when given to criminals make them tell the truth
2. Morphine is Olien given to persons who have undergone surgery as a painkiller
3. Chewing tobacco lowers blood pressure and heart rate
4. Cocaine is given to patients who have undergone surgery and recovering slowly.

Answer: 2. Morphine is Olien given to persons who have undergone surgery as a pain killer

Question 13. A patient is suspected to be suffering from acquired immune deficiency syndrome. Which diagnostic technique will you recommend for its detection?

1. ELISA
2. MRI
3. Ultrasound
4. Widal

Answer: 1. ELISA

Human Health And Disease Mcq For Neet

Question 14. The side effects of the use of anabolic steroids in females are

1. Aggressiveness
2. Masculinisation
3. Enlargement of clitoris and deepening of voice
4. All the above

Answer: 4. All the above
.
Question 15. At what stage does HIV infection usually show symptoms of AIDS

1. When the infecting retrovirus enters host cells
2. When viral DNA is produced by reverse transcriptase
3. Within 15 days of sexual contact with an infected person
4. When HIV replicates rapidly in the helper T- lymphocytes and damages a large number of these.

Answer: 4. When HIV replicates rapidly in the helper T-lymphocytes and damages a large number of these.

Question 16. Antigens are:

1. The micro-organisms which are the source of disease in the body
2. A foreign body which is harmful to the animal and evokes the generation of antibodies
3. The substance generated in the body in response to the infection
4. None of these.

Answer: 2. A foreign body which is harmful to the animal and evokes the generation of antibodies

Question 17. Koch’s postulates include which of the following?

1. The organism must be regularly found in the body of the patient
2. Must be isolated and grown in an artificial medium
3. When the culture is inoculated into the healthy person it must cause disease and can be recovered again
4. All the above.

Answer: 4. All the above.

Question 18. Reservoir of infection is:

1. Site where pathogens reside without causing any damage
2. Soil, water and air
3. Another animal
4. Another person who is suffering.

Answer: 1. Site where pathogens reside without causing any damage

Human Health And Disease Class 12 Mcq

Question 19. Antibodies fight against:

1. Starvation
2. Stress
3. Thirst
4. Infection.

Answer: 4. Infection.

Human Health and Disease NEET Questions Question 20. The humoral immune system consists of:

1. A family of diverse proteins present in body fluids
2. Some special types of cells destroy the pathogens
3. Both cells as well as polysaccharides
4. All the above.

Answer: 1. A family of diverse proteins present in body fluids

Question 21. How many principal lines of defence are present in the body?

1. Two
2. Three
3. Five
4. Innumerable.

Answer: 2. Three

Question 22. Which of the following is a correct statement?

1. B-cells directly engulf the pathogenic bacteria
2. B-cells produce antibodies soon after they are produced
3. B-cells produce a large clone of plasma cells soon after it is formed
4. The B-cells produce the plasma cells in the body only after they are triggered by a specific antigen.

Answer: 4. The B-cells produce the plasma cells in the body only after they are triggered by a specific antigen.

Question 23. Antiserum is a serum containing:

1. Antigens
2. Leucocytes
3. Active antibodies
4. None of the above.

Answer: 3. Active antibodies

Question 24. Interferon is a glycoprotein which possesses:

1. Antiviral activity
2. Antifungal activity
3. Antiparasitic activity
4. Antibacterial activity.

Answer: 1. Antiviral activity

Neet Mcqs On Human Health And Disease With Answers

Question 25. Antibodies are:

1. A large family of protein molecules produced by the body’s defence cells in the body fluids neutralise the antigens
2. The chemicals produced by the invading microbes destroy and damage the body’s cells
3. Certain substances enclosed in lymphocytes
4. None of the above.

Answer: 1. A large family of protein molecules produced by the body’s defence cells in the body fluids which neutralise the antigens

Question 26. The mode of transmission of communicable diseases is dealt by a branch of science named:

1. Epidemiology
2. Immunology
3. Aetiology
4. Angiology.

Answer: 1. Epidemiology

Question 27. The degree of pathogenicity is called:

1. Infestation
2. Infection
3. Virulence
4. Resistance.

Answer: 3. Virulence

Question 28. Which one of the following diseases is caused by bacteria?

1. Chicken-pox
2. Poliomyelitis
3. Measles
4. Tetanus.

Answer: 4. Tetanus.

Question 29. Which one of the following communicable diseases is not caused by bacteria?

1. Diphtheria
2. Typhoid
3. Leprosy
4. Poliomyelitis.

Answer: 4. Poliomyelitis.

Question 30. The causative organism of cholera is a:

1. Bacterium
2. Protozoan
3. Nematode
4. Virus.

Answer: 1. Bacterium

Neet Mcqs On Human Health And Disease With Answers

Question 31. Tetanus is caused by:

1. Bacterium
2. Fungus
3. Protozoan
4. Virus.

Answer: 1. Bacterium

Question 32. Poliomyelitis is caused by

1. Bacteria
2. Virus
3. Protozoan
4. Nematodes.

Answer: 2. Virus

Question 33. AIDS is caused by:

1. Cocci
2. Bacilli
3. TMV
4. HIV.

Answer: 4. HIV.

Question 34. Invention and study of the effects of medicines on the organism is known as:

1. Toxicology
2. Pharmacology
3. Pharmacy
4. Haematology.

Answer: 2. Pharmacology

Question 35. DPT vaccine is given to infants to immunize them against:

1. Diphtheria, pneumonia and typhoid
2. Diphtheria, whooping cough and tetanus
3. Diarrhoea, pneumonia and tuberculosis
4. Diphtheria, whooping cough and typhoid.

Answer: 2. Diphtheria, whooping cough and tetanus

Question 36. Dengue fever is caused by:

1. Bacteria
2. Plasmodium
3. Virus
4. Entamoeba histolytica.

Answer: 3. Virus

Question 37. Vims cause contagious epidemic disease with high fever and a rash all over the body. Its incidence is among children. It’s one attack that gives immunity. Which one is of the following?

1. Mumps
2. Plague
3. Brain fever
4. Measles.

Answer: 4. Measles.

Question 38. Syphilis is a venereal disease. It is caused by:

1. Neisseria
2. Vibrio
3. Corynebacterium
4. Treponema pallidum.

Answer: 4. Treponema pallidum.

MCQs on Human Health and Diseases Question 39. The contagious diseases are:

1. Measles
2. Chickenpox
3. Whooping cough
4. All the above.

Answer: 4. All the above.

Common Human Diseases Mcqs For Neet

Question 40. Where are the gametocytes of Plasmodium first formed and found?

1. Liver of man
2. Stomach of female mosquito
3. Blood of man
4. RBC of the blood of man.

Answer: 4. RBC of the blood of man.

Question 41. Entamoeba histolytica has:

1. Well developed pseudopodia
2. Contractile vacuole
3. Both (1) and (2)
4. None of the above.

Answer: 4. None of the above

Question 42. Which mosquito actually transmits malaria and acts as an intermediate host of Plasmodium?

1. Male Anopheles
2. Female Anopheles
3. Male Culex
4. Female Culex.

Answer: 2. Female Anopheles

MCQs on Human Health and Diseases Question 43. The credit of working out the complicated life cycle of Plasmodium goes to:

1. Louis Pasteur
2. John Snow
3. Robert Koch
4. Ronald Ross.

Answer: 4. Ronald Ross.

Question 44. The symptoms of Malaria fever appear at their peak in a patient when:

1. Sporozoites enter liver
2. Merozoites enter red blood cells
3. Red blood cells rupture and haemozoin is released
4. Gametocytes are formed.

Answer: 3. Red blood cells rupture and haemozoin is released

Question 45. Which of the following worms is viviparous?

1. Wuchereria bancrofti
2. Ancylostoma dudoenale
3. Ascaris lumbricodes
4. Taenia solium.

Answer: 1. Wuchereria bancrofti

Question 46. The infective stage of plasmodium is:

1. Trophozoite
2. Sporozoite
3. Merozoite
4. Schizont.

Answer: 2. Sporozoite

Question 47. A chronic contagious eye disease, caused by a virus is called:

1. Thrombosis
2. Myopia
3. Conjunctivitis
4. Night blindness.

Answer: 3. Conjunctivitis

Question 48. The region of the body where the poliomyelitis virus multiplies is:

1. Nerve cells
2. Muscle cells
3. Intestinal cells
4. None of the above.

Answer: 1. Nerve cells

Question 49. The disease Tilariasis’ is caused by the worm:

1. Wuchereria bancrofti
2. Ancylostoma duodenale
3. Trichinella spiralis
4. Enterobius vermicularis.

Answer: 1. Wuchereria bancrofti

Common Human Diseases Mcqs For Neet

Question 50. The mode of transmission of the disease Filariasis is:

1. Bite of mosquito
2. Eating unwashed eatables
3. Eating unripe Pork
4. Both (2) and (3).

Answer: 1. Bite of mosquito

Question 51. Which mosquito aids in the transmission of the disease filariasis?

1. Male Anopheles
2. Female Anopheles
3. Culex
4. Both (1) and (2).

Answer: 3. Culex

Question 52. A disease characterised by chronic sleeplessness is:

1. Insomnia
2. Jaundice
3. Sleeping sickness
4. Nervous breakdown.

Answer: 1. Insomnia

Question 53. Trachoma is caused by the infection of:

1. Virus
2. Fungus
3. Nematode
4. Bacterium.

Answer: 1. Virus

Question 54. Chickenpox can be easily identified from measles due to the:

1. High fever
2. Irritation all over the skin
3. Dew drop-like rashes
4. Sneezing and water discharge from the nose.

Answer: 3. Dew drop-like rashes

Question 55. Varicella virus causes:

1. Smallpox
2. Chickenpox
3. Measles
4. Influenza

Answer: 2. Chickenpox

Question 56. Elephantiasis is caused by:

1. Tapeworm
2. Wuchereria
3. Ascaris
4. Culex.

Answer: 2. Wuchereria

Question 57. The incubation period of smallpox is:

1. 2 days
2. 12 days
3. 12 hours
4. 2 to 12 days.

Answer: 2. 12 days

Question 58. The infective period of enteric fever is:

1. 6 hours
2. 6 days
3. 6 weeks
4. 6 minutes.

Answer: 2. 6 days

Common Human Diseases Mcqs For Neet

Question 59. Protection against poliomyelitis and tetanus is done simultaneously by:

1. Sulpha drugs
2. Gamma globulin inoculation
3. Multiple vaccines
4. Pasteur treatment.

Answer: 3. Multiple vaccine

Question 60. After floods, the victims are usually attacked by:

1. Appendicitis
2. Peritonitis
3. Rabies
4. Cholera.

Answer: 4. Cholera.

NEET Biology Inflorescence And Flower Multiple Choice Questions And Answers

Question 1. If a raceme inflorescence is branched, it is called :

1. Umbel
2. Panicle
3. Head
4. Cymose.

Answer: 2. Panicle

Question 2. The arrangement of flowers in a raceme is :

1. Basipetal
2. Acropetal
3. Head
4. Cymose.

Answer: 2. Acropetal

Question 3. A raceme of sessile flowers is termed :

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

Answer: 3. Spike

Morphology Of Flowering Plants Mcq For Neet

Question 4. Multiparous cyme is the characteristic of :

1. Calotropis
2. Acacia
3. Begonia
4. Bignonia.

Answer: 1. Calotropis

Read and Learn More NEET Biology Multiple Choice Question and Answers

Morphology of Flowering Plants NEET Questions Question 5. ln Mimosa pudica, the inflorescence is :

1. Raceme
2. Cymose head
3. Spike
4. Umbel.

Answer: 2. Cymose head

Question 6. Involucre forms the cup in the inflorescence of :

1. Fig
2. Salvia
3. Sunflower
4. Poinsettia.

Answer: 4. Poinsettia.

Question 7. Zig-development of the inflorescence axis is an example of:

1. Helicoid cyme
2. Verticillasrer
3. Umbel
4. Scorpioid.

Answer: 1. Helicoid cyme

Question 8. Considering the angiosperm flower :

1. Anemophilous are more advanced than regular flowers
2. Irregular flowers are more primitive than regular flowers
3. A solitary axillary or solitary terminal flower is more primitive than the inflorescence, likewise, capitulum and umbel are the most advanced forms of inflorescence.
4. An inflorescence is more primitive than a solitary axillary or solitary terminal flower and the umbel is more primitive than a spike.

Answer: 3. A solitary axillary or solitary terminal flower is more primitive than the inflorescence, likewise capitulum and umbel are the most advanced forms of inflorescence.

Question 9. In Musaceae, the inflorescence is :

1. Spike
2. Head
3. Capitulum
4. Spadix.

Answer: 4. Spadix.

Question 10. Ovule of Opuntia is coiled and called:

1. Anatropous
2. Circinotropous
3. Hemitropous
4. Amphitropous.

Answer: 2. Circinotropous

Morphology Of Flowering Plants Mcq For Neet

Question 11. An inflorescence in which flowers arise from different levels but reach the same level is called :

1. Catkin
2. Umbel
3. Corymb
4. Spadix.

Answer: 3. Corymb

Question 12. Cauliflory is :

1. Formation of flowers in clusters
2. Production of flowers on young branches
3. Production of flowers on old stem from new buds
4. Formation of plants from epiphyllous buds.

Answer: 3. Production of flowers on old stem from new buds

Question 13. Feathery stigma is present in :

1. Wheat
2. Pea
3. Ceasalpinia
4. Darura.

Answer: 1. Wheat

Question 14. The inflorescence in candytuft is :

1. Raceme
2. Corymb
3. Cyme
4. Umbel.

Answer: 2. Corymb

Question 15. Hypanthodium is a characteristic inflorescence of:

1. Ficus
2. Pineapple
3. Mulberry
4. Poinsettia.

Answer: 1. Ficus

Morphology Of Flowering Plants Mcq For Neet

Question 16. In onion, the inflorescence is :

1. Umbellate cyme
2. Catkin
3. Raceme
4. Corymb.

Answer: 1. Umbellate cyme

Question 17. In a compound umbel, each umbellet is subtended by :

1. Involucre
2. Ramenta
3. Involucral
4. Bracteole.

Answer: 3. Involucral

Question 18. The inflorescence of Acacia is to be distinguished as a:

1. Spike
2. Spikelet
3. Cymose head
4. Raceme.

Answer: 3. Cymose head

Question 19. The peduncle is :

1. Floral axis
2. Inflorescence axis
3. Thalamus
4. Bract.

Answer: 2. Inflorescence axis

Question 20. Inflorescence with a female flower in the middle and male flowers all around surrounded by a cup-like structure is known as :

1. Catkin
2. Cyathium
3. Verticillaster
4. Capitulum.

Answer: 2. Cyathium

Neet Mcqs On Morphology Of Flowering Plants

Question 21. A brightly colored bract-like covering associated with the banana the inflorescence is called :

1. Spathe
2. Scape
3. Spiral
4. Scapigeron.

Answer: 1. Spathe

Question 22. Inflorescence is :

1. Number of flowers present on an axis
2. Arrangement of flowers on an axis
3. Method of the opening of flowers
4. Type of flowers bome on the peduncle.

Answer: 2. Arrangement of flowers on an axis

Question 23. In monocots male gametophyte is :

1. Megaspore
2. Nucellus
3. Microspore
4. Tetrad.

Answer: 3. Microspore

Question 24. Inflorescence of mulberry is :

1. Catkin
2. Raceme
3. Spadix
4. Capitulum.

Answer: 1. Catkin

Question 25. A catkin of unisexual flowers is found in :

1. Mulberry
2. Wheat
3. Onion
4. Fig.

Answer: 1. Mulbeny

Question 26. The inflorescence of wheat is :

1. Spike
2. Spikelet
3. Spike of spikelets
4. Panicle of spikelets.

Answer: 3. Spike of spikelets

Question 27. Flower is a :

1. Modified cone
2. Modified spike
3. Modified branch system
4. Modified reproductive shoot.

Answer: 4. Modified reproductive shoot.

Morphology Of Plants Mcqs For Neet With Answers

Question 28. Flowers are always present in :

1. Cryptogams
2. Pteridophytes
3. Angiosperms
4. Bryophytes.

Answer: 3. Angiosperms

Question 29. The floral formula represents :

1. Number and arrangement of floral parts
2. Number of flowers in an inflorescence
3. Type of flowers in a family
4. None of the above.

Answer: 1. Number and arrangement of floral parts

Question 30. Flowers devoid of sepals and petals are called as :

1. Florets
2. Monothecous
3. Achlamydeous
4. None of the above.

Answer: 3. Achlamydeous

Question 31. Unisexual flowers are also known as :

1. Diclinous
2. Uniparous
3. Unitemic
4. None of the above.

Answer: 1. Diclinous

Question 32. In the case of the superior ovary, the thalamus is :

1. Superior
2. Epigynous
3. Hypogynous
4. None of the above.

Answer: 3. Hypogynous

Morphology Of Plants Mcqs For Neet With Answers

Question 33. The arrangement of sepals and petals in a bud condition is also called :

1. Inflorescence
2. Aestivation
3. Venation
4. Placentation.

Answer: 2. Aestivation

Question 34. Which type of inflorescence occurs in Ficus?

1. Verticillaster
2. Hypanthodium
3. Cymose
4. Racemose.

Answer: 2. Hypanthodium

Question 35. Spike with unisexual flowers or catkin occurs in :

1. Mulberry
2. Grass
3. Wheat
4. Callistemon.

Answer: 1. Mulberry

Question 36. An edible inflorescence is :

1. Raphanus sativus
2. Brassica oleracea
3. Brassica rapa
4. Mustard.

Answer: 2. Brassica oleracea

Question 37. The smallest flowering plant is :

1. Woffia
2. Polyalthia
3. Rffiesia
4. Mimosa.

Answer: 1. Woffia

Morphology Of Plants Mcqs For Neet With Answers

Question 38. A bi-or tricarpellary syncarpous unilocular ovary having one ovule at the base represents the placentation of the type :

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

Answer: 4. Basal.

Question 39. Umbel inflorescence occurs in :

1. Coriandrum
2. Colocasia
3. Musa
4. Sunflower.

Answer: 1. Coriandrum

Question 40. A plant is termed monoecious if it bears :

1. Both male and female flowers
2. Either male or female flowers
3. Male, female, and bisexual flowers
4. Male, female, and neutral flowers.

Answer: 1. Both male and female flowers

Question 41. Monadelphous stamens occur in :

1. Lady’s Finger
2. Hibiscus
3. Gossypium
4. All of the above

Answer: 4. All of the above

Question 42. From the life cycle point of view, the most important part of a plant is :

1. Flower
2. Leaf
3. Stem
4. Root.

Answer: 1. Flower

Previous Year Neet Questions On Plant Morphology

Question 43. The ovule is attached to the placenta by :

1. Petiole
2. Pedicel
3. Funiculus
4. Hilum.

Answer: 3. Funiculus

Morphology of Flowering Plants NEET Questions Question 44. In a flower the placenta is a tissue :

1. In the corolla tube where filaments are attached
2. In other lobes where pollens are attached
3. In the ovary where the ovules are attached
4. On the thalamus where floral whorls are attached.

Answer: 3. In the ovary where the ovules are attached

Question 45. Which of the following has male and female flowers on different plants :

1. Ranunculus
2. Carrica papaya
3. Caesalpinia
4. Cotton.

Answer: 2. Carrica papaya

Question 46. The term tetradynamous is applied when there are :

1. 6-Stamens-2 long and 4 shorl
2. 4 Stamens-2 long and 2 short
3. 6 Stamens-2 short in the outer whorl and 4 long in the inner whorl
4. 6 Stamens-2 short and 4 long

Answer: 3. 6 Stamens-2 short in the outer whorl and 4 long in the inner whorl

Question 47. The vexillum, wings, and keel in pea flowers constitute :

1. Calyx
2. Corolla
3. Androecium
4. Gynaecium.

Answer: 2. Corolla

Question 48. Staminodes are found in :

1. Malvaceae
2. Liliaceae
3. Caesalpinoideae
4. Mimosoideae.

Answer: 3. Caesalpinoideae

Question 49. A monoecious anther is :

1. A sterile stamen
2. A stamen with two lobes
3. Another with one lobe
4. Fused in all parts.

Answer: 3. Anther with one lobe

Previous Year Neet Questions On Plant Morphology

Question 50. A stalk-bearing androecium and gynoecium are called :

1. Anthropocene
2. Andropore
3. Sporangiophore
4. Gynandrophore.

Answer: 4. Gynandrophore.

Question 51. What is the technical term used for a sterile stamen?

1. Spur
2. Staminode
3. Stallion
4. Staminate.

Answer: 2. Staminode

Question 52. Glumes are modified :

1. Leaves
2. Bracts
3. Calyx
4. None of the above.

Answer: 2. Bracts

Question 53. Anemophilous Plants have :

1. Small petals and stick pollen
2. No petals and light pollen
3. Colored petals and large pollen
4. Colored petals and heavy pollen.

Answer: 2. No petals and light pollen

Question 54. Diadelphous condition is present on :

1. Citrus
2. Bombyx
3. Pisum
4. Brassica.

Answer: 3. Pisum

Important Neet Questions On Plant Morphology

Question 55. Number of female flowers in a cyathium is :

1. 1
2. 2
3. 3
4. Several.

Answer: 1. 1

Question 56. Cleistogamous flowers are found in :

1. Ficus bengalensis
2. Commelina benghalensis
3. Adina portfolio
4. Anthoc ephalus cadamba.

Answer: 2. Commelina benghalensis

Question 57. The inflorescence in the family Compositae is :

1. Capitulum
2. Spadix
3. Umbel
4. Catkin.

Answer: 1. Capitulum

Question 58. Superficial placentation is seen in :

1. Cosmos
2. Calotropis
3. Nymphaea
4. Brassica.

Answer: 3. Nymphaea

Question 59. Spadix inflorescence occurs in :

1. Mulberry
2. Banana
3. Coriander
4. Delonix.

Answer: 2. Banana

Important Neet Questions On Plant Morphology

Question 60. The ovule is attached to the funiculus at the point called :

1. Pedicel
2. Petiole
3. Anthropocene
4. Hilum.

Answer: 4. Hilum.

Question 61. When stamens are adnate to perianth leaves it is known AS:

1. Episepalous
2. Epipetalous
3. Gynandrous
4. Epiphyllous.

Answer: 4. Epiphyllous.

Question 62. The longest stigma is found in :

1. Zea mays
2. Dioscorea
3. Date palm
4. Bamboo.

Answer: 1. Zea mays

Question 63. A flower is said to be actinomorphic if it can be divided in two :

1. Similar halves by a single vertical section.
2. Exactly equal halves by any vertical section through the center
3. Halves having sepals and petals in equal numbers
4. Both ‘A’ and ‘C’.

Answer: 2. Exactly equal halves by any vertical section through the center

Question 64. Perianth is found in a flower in which :

1. Calyx and corolla are not distinguishable
2. Stamens are leaf-like
3. Corolla is leaf-like but calyx is coloured
4. None of the above.

Answer: 1. Corolla is leaf-like but calyx is coloured

Important Neet Questions On Plant Morphology

Question 65. Hypanthodium is :

1. Thalamus
2. Fruit
3. Inflorescence
4. Ovary.

Answer: 3. Inflorescence

Question 66. Persistent calyx forms a dry bladder-like enclosing edible berry in :

1. Nicotiana
2. Solanum
3. Physalis
4. Capsicum.

Answer: 3. Physalis

Question 67. The colored structures associated with the flowers of Poinsettia (dogwood) are :

1. Petals
2. Bracts
3. Perianth
4. Carpels.

Answer: 2. Bracts

Question 68. A bisexual flower that never opens in its lifespan is called:

1. Heterogamous
2. Homogamous
3. Cleistogamous
4. Dichogamous.

Answer: 3. Cleistogamous

Question 69. Hypanthodium inflorescence is found in :

1. Coriander
2. Sunflower
3. Cauliflower
4. Fig.

Answer: 4. Fig.

Question 70. Stamens with free anthers but filaments fused into several groups are:

1. Polyadelphous
2. Diadelphous
3. Monadelphous
4. Syngenesious

Answer: 1. Polyadelphous

Question 71. In the flowering plants, angiosperms, an ovule represents:

1. Megasporophyll
2. Megasporangium
3. A megaspore
4. A megaspore mother cell.

Answer: 2. Megasporangium

Morphology of Flowering Plants MCQ With Answers Question 72. An orthotropous ovule is one in which the micropyle and chalazaarc’.

1. Oblique of funiculus
2. At the right angle to the funiculus
3. Parallel to funiculus
4. In the straight line of funiculus.

Answer: 4. In the straight line of funiculus.

Question 73. Pappus is a modification of :

1. Calyx
2. Corolla
3. Stamens
4. Gynoecium.

Answer: 1. Calyx

Question 74. Gynandrophore is found in:

1. Malverstrum
2. Brassica campestris
3. Gynadropsis
4. Allium cepa.

Answer: 3. Gynadropsis

Question 75. Diadelphous slamens occur in :

1. Gramineae
2. Cucurbitaceae
3. Papilionatae
4. Malvaceae.

Answer: 4. Malvaceae.

Question 76. Synandrous refers to the fusion of:

1. Filaments only
2. Anthers only
3. Filaments and anthers
4. Anthers and gynoecium.

Answer: 3. Filaments and anthers

Question 77. In synanthropic condition :

1. Anthers of a flower are fused but the filaments are free
2. Filaments of androecium are used but anthers are free
3. Filaments and anthers are fused
4. Anthers filaments and gynoecium are fused.

Answer: 1. Anthers of a flower are fused but the filaments are free

Question 78. In a flowering plant the largest number of haploid cells occur in :

1. Ovule
2. Microsporangia
3. Root tip
4. Cambium.

Answer: 2. Microsporangia

Question 79. Which of the following is a polycarpic plant?

1. Pea
2. Agave
3. Pear
4. Bamboo.
5. Agave

Answer: 3. Bamboo.

Question 80. Syngenesious condition is found in :

1. Acacia
2. Peruniu
3. Sunflower
4. Hibiscus.

Answer: 3. Sunflower

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

Morphology Of Flowering Plants NEET 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

Morphology Of Flowering Plants NEET 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 Plants NEET

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

Morphology Of Plants NEET

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.

Root Stem Leaf Morphology 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).

Root Stem Leaf Morphology 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

Root Stem Leaf Morphology NEET

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.

Floral Structure And Functions NEET

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):

Floral Structure And Functions NEET

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.

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.

Floral Structure And Functions NEET

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 Angiosperms NEET

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 Angiosperms NEET

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 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.

Animal Husbandry And Plant Breeding NEET

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.

Green Revolution And Its Impact NEET

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.

Food Production And Biotechnology NEET

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.

Apiculture And Sericulture NEET 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.

Apiculture And Sericulture NEET 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.

Genetically Modified Crops NEET

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.

Genetically Modified Crops NEET

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.

Dairy And Poultry Management NEET

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

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

Enhancement In Food Production Mcq For Neet

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

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

Enhancement In Food Production Mcq For Neet

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

Neet Biology Food Production Mcqs

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

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.

Food Production And Management Mcq Neet

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.

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.

Food Production And Management Mcq Neet

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

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

Food Production And Management Mcq Neet

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

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)

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

Food Production And Management Mcq Neet

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

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

Biotechnology In Food Production Mcq

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).

Biotechnology In Food Production Mcq

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

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

Biotechnology In Food Production Mcq

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)

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

Food Security And Gm Crops Mcq Neet

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

Food Security And Gm Crops Mcq Neet

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

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

Food Security And GM Crops Mcq Neet

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

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

Food Security And GM Crops Mcq Neet

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

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

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

Enhancement In Food Production Mcq For Neet

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

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

Enhancement In Food Production Mcq For Neet

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.

Gene Expression And Regulation NEET 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.

Gene Regulation In Prokaryotes And Eukaryotes NEET

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.

Lac Operon Model NEET

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.

Control Of Gene Expression NEET

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)

Transcription And Translation NEET 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.

Transcription And Translation NEET Notes

• 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

Gene Expression MCQs For NEET

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

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

Gene Expression MCQs For NEET

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

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

Gene Expression MCQs For NEET

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

Gene Expression MCQs For NEET

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

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

NEET Biology Gene Regulation Questions

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

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

NEET Biology Gene Regulation Questions

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

Operon Model MCQs For NEET

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

Operon Model MCQs For NEET

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

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

NEET Previous Year Questions On Gene Regulation

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

NEET Previous Year Questions On Gene Regulation

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

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

Lac Operon MCQs For NEET

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

Lac Operon MCQs For NEET

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

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

Lac Operon MCQs For NEET

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

Lac Operon MCQs For NEET

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

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

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%

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

Transcription And Translation NEET MCQs

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

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

Transcription And Translation NEET MCQs

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

Transcription And Translation NEET MCQs

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

Gene Expression MCQs For NEET

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

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

Gene Expression MCQs For NEET

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

NEET Biology Gene Regulation Questions

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

NEET Biology Gene Regulation Questions

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.

NEET Biology Gene Regulation 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.

Operon Model MCQs For NEET

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.

Operon Model MCQs For NEET

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

Operon Model MCQs For NEET

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’)

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

NEET Previous Year Questions On Gene Regulation

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.

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

NEET Previous Year Questions On Gene Regulation

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.

Cell Wall And Cell Membrane Neet Notes

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.

Structure And Function Of Cell Membrane Neet

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.

Difference Between Cell Wall And Cell Membrane Neet

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.