Top 25+ Biotechnology and Its Applications - Biology Questions and Answers For NEET 2024 Exam Preparation

Q1. The aims and objectives of Genetic Engineering Approval Committee are

1. to permit the use of genetically modified organisms and their product for commercial applications.
2. to adopt the procedures for restriction, production and application of GM organisms.
3. approval to conduct large scale field trails and release of transgenic crops in the environment.

Which of the above statements are correct?

1. I and III
2. I and II
3. II and III
4. I, II and III

Answer: (d)

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Q2. Consider the following four statements

1. The first transgenic buffalo, Rosie produced milk which was human alpha-lactal albumin enriched.
2. Restriction enzymes are used in isolation of DNA from other macro-molecules.
3. Downstream processing is one of the steps of R-DNA technology.
4. Disarmed pathogen vectors are also used in transfer of R-DNA into the host.

Which are the two statements incorrect?

1. Statement (iii) and (iv)
2. Statement (ii) and (iii)
3. Statement (i) and (iii)
4. Statement (i) and (ii)

Answer: (d)

Transgenic Rosie is actually cow. Restriction enzymes cut the DNA at specific sites.

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Q3. Some of the characteristics of Bt cotton are

1. high yield and production of toxic protein crystals which kill dipteran pests
2. medium yield, long fibre and resistance to beetle pests
3. long fibre and resistance to aphids
4. high yield and resistance to bollworms

Answer: (d)

Bt toxin genes were isolated from Bacillus thuringiensis and incorporated into cotton plant. The genetically modified crop is called Bt cotton. Bt cotton has the following useful characteristics: pest resistance, herbicide tolerance, high yield and resistance to boll worm infestation.

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Q4. RNA interference involves

1. Synthesis of cDNA from RNA using reverse transcriptase
2. Synthesis of mRNA from DNA
3. Silencing of specific mRNA due to complementary RNA
4. Interference of RNA in synthesis of DNA

Answer: (c)

RNAi is a method of cellular defense in all eukaryotes. It is a system within living cells that helps to control the activity of specific genes. This method involves silencing of mRNA due to complementary double stranded RNA that prevents translation of target gene or mRNA[silencing]. Source of ds RNA is retrovirus (having RNA genome) or transposons (mobile genetic material).

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Q5. Genetic modification has

1. reduced reliance on chemical pesticides.
2. reduced post-harvest losses.
3. increased efficiency of minerals usage by the plants.
4. enhanced nutritional value of the food.

Which of the statements given above are correct?

1. I, II and III
2. I, II, III and IV
3. II, III and IV
4. III and IV

Answer: (b)

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Q6. The two polypeptides of human insulin are linked together by

1. disulphide bridges
2. covalent bond
3. hydrogen bonds
4. phosphodiester bond.

Answer: (a)

Human insulin is made up of 51 amino acids arranged in two polypeptide chains. Chain A has 21 amino acids and chain B has 30 amino acids. The two polypeptide chains are interconnected by disulphide bridges or S-S-linkages.

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Q7. Bacillus thuringiensis forms protein crystals which contain insecticidal protein. This protein

1. is coded by several genes including the gene cry.
2. binds with epithelial cells of midgut of the insect pest ultimately killing it.
3. is activated by acid pH of the foregut of the insect pest.
4. does not kill the carrier bacterium which is itself resistant to this toxin.

Answer: (b)

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Q8. Golden rice is a genetically modified crop plant where the incorporated gene is meant for biosynthesis of :

1. Vitamin C
2. Vitamin B
3. Vitamin A
4. Omega 3

Answer: (c)

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Q9. In Bt cotton, the Bt toxin present in plant tissue as protoxin is converted into active toxin due to

1. alkaline pH of the insect gut
2. presence of conversion factors in insect gut
3. action of gut microorganisms
4. acidic pH of the insect gut

Answer: (a)

Soil bacterium Bacillus thuringiensis produces proteins that kill certain insects like lepidopterans (tobacco budworm, armyworm), coleopterans (beetles) and dipterans (flies, mosquitoes). B. thuringiensis forms some protein crystals. These crystals contain a toxic insecticidal protein. This toxin does not kill the Bacillus (bacterium) because it exists as inactive protoxins in them.

But, once an insect ingests it, it is converted into an active form of toxin due to the alkaline pH of the alimentary canal. The activated toxin binds to the surface of midgut epithelial cells and create pores that cause swelling and lysis and finally cause death of the insect.

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Q10. Bt toxin is

1. intracellular crystalline protein.
2. intracellular lipids.
3. extracellular crystalline protein.
4. intracellular polysaccharide.

Answer: (a)

Bt toxin (obtained from Bacillus thuringiensis) is intracellular crystalline protein which are toxic to insects. It is widely used as a biological pesticide.

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Q11. Some of the characteristics of Bt cotton are

1. high yield and production of toxic protein crystals which kill dipteran pests
2. Medium yield, long fibre and resistance to beetle pests
3. Long fibre and resistance to aphids
4. High yield and resistance to bollworms

Answer: (d)

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Q12. Cry I endotoxins obtained from Bacillus thuringiensis are effective against

1. mosquitoes
2. bollworms
3. nematodes
4. flies

Answer: (b)

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Q13. Read the following four statements (1 to 4) about certain mistakes in two of them.

1. The first transgenic buffalo, Rosie produced milk which was human alpha-lactal albumin enriched.
2. Restriction enzymes are used in isolation of DNA fro mother macro-molecules.
3. Downstream processing is one of the steps of R-DNA technology.
4. Disarmed pathogen vectors are also used in transfer ofR-DNA into the host.

Which are the two statements having mistakes?

1. Statement 3 and 4
2. Statement 2 and 3
3. Statement 1 and 3
4. Statement 1 and 2

Answer: (d)

Transgenic Rosie is actually cow. Restriction enzymes cut the DNA at specific sites.

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Q14. Match column-I with column-II and choose the correct option.

Codes:

1. A – II; B – I; C – III; D – IV
2. A – II; B – I; C – IV; D – III
3. A – II; B – III; C – I; D – IV
4. A – IV; B – I; C – II; D – III

Answer: (d)

Forensic science is the scientific method of gathering and examining information about the past which is then used in a court of law. It is related to DNA fingerprinting.

ELISA (Enzyme-linked immunosorbent assay),used in AIDS, is a rapid immunochemical test that involves an enzyme used for measuring a wide variety of tests of body fluids. ELISA tests detect substances that have antigenic properties, primarily proteins rather than small molecules and ions, such as glucose and potassium.

Probe is a radioactive DNA/RNA.

Alpha 1 antitrypsin is used to treat emphysema (a condition in which the air sacs of the lungs are damaged and enlarged, causing breathlessness). Alpha - 1 antitrypsin is a protein made by cells in the liver and protect the lungs from damage caused by other types of proteins called enzymes.

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Q15. In India, the organisation responsible for assessing the safety of introducing genetically modified organisms for public use is

1. Council for Scientific and Industrial Research (CSIR)
2. Research Committee on Genetic Manipulation (RCGM)
3. Indian Council of Medical Research (ICMR)
4. Genetic Engineering Approval Committee (GEAC)

Answer: (d)

In India, Genetic Engineering Approval Committee, i.e. GEAC is responsible for assessing the safety of introducing genetically modified organisms for public use. GEAC comes under the Ministry of Environment and Forests.

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Q16. Assertion: Flavr Savr tomato is transgenic tomato that is capable of remaining fresh and retaining the flavour for a longer time.

Reason: In this, production of pectin degrading Polygalactouronase is blocked.

1. If both Assertion and Reason are true but the Reason is not the correct explanation of the Assertion.
2. If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
3. If Assertion is true but Reason is false.
4. If both Assertion and Reason are false.

Answer: (b)

Flavr Savr Tomato remains fresh by blocking the protein degrading enzyme, polygalacturonase.

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Q17. A functional ADA cDNA can be introduced into cells of the patients receiving gene therapy by using vector constituted by

1. Reovirus
2. E. coli
3. Retrovirus
4. Agrobacterium

Answer: (c)

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Q18. Which of the following statements is/are incorrect?

1. Animal insulin is slightly different from the human insulin
2. Insulin used for diabetes, was easier extracted from the pancreas of slaughtered pig and cattle
3. Animal insulin causes some undesirable side effects such as allergy
4. None of the above

Answer: (d)

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Q19. A protoxin is

1. a denatured toxin
2. a primitive toxin
3. toxin produced by protozoa
4. inactive toxin

Answer: (d)

A protoxin is an inactive toxin. The word 'pro' in protoxin means 'inactive form'. B. thuringiensis forms protein crystal that contains a toxic insecticidal protein (Bt toxin).

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Q20. Which of the following is true for Golden rice?

1. It is pest resistant, with a gene from Bacillus thuringiensis.
2. It is vitamin A enriched, with a gene from daffodil.
3. It has yellow grains, because of a gene introduced from a primitive variety of rice.
4. It is drought tolerant, developed using Agrobacterium vector

Answer: (b)

Rice is a staple food in many countries, particularly in Asia, but does not contain vitamin A or its immediate precursors. By inserting two genes from daffodil and one gene from a bacterial species into rice plants, Swiss researchers have produced rice capable of synthesising b-carotene, the precursor of vitamin A.

Vitamin A is required by all individuals as it is present in retina of eyes. Deficiency of vitamin A causes night blindness and skin disorders. This rice is called 'Golden rice' because of yellow colour of rice grains due to the presence of b-carotene.

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Q21. α-I antitrypsin is

1. an enzyme
2. an antacid
3. used to treat arthritis
4. used to treat emphysema

Answer: (d)

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Q22. Read the following statements.

1. Pigs are the most preferred mammals for studies of gene transfer.
2. A trans gene is a foreign gene incorporation of which in a host cell can make it transgenic.
3. ADA deficiency causes Severely Combined Immuno Deficiency (SCID).
4. Two insulin polypeptides are cross-linked via H-bonds.

Which of the above statements are correct?

1. II and III
2. Only II
3. I, II and III
4. Only IV

Answer: (a)

Statements II and III are correct, while statements I and IV are incorrect and can be corrected as

• Mice are the most preferred mammals for the studies of gene transfer studies as their generation time is short, easy to keep, etc.
• The two insulin polypeptides are cross-linked via disulphide bonds.

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Q23. A 'new' variety of rice was patented by a foreign company, though such varieties have been present in India for a long time. This is related to

1. Lerma Rojo
2. Sharbati Sonora
3. Co-667
4. Basmati

Answer: (d)

In 1997, a Texas company got patent rights on Basmati rice through the US Patent and Trademark Office. This allowed the company to sell a 'new' variety of Basmati, in the US and abroad. This new variety of Basmati had actually been derived from Indian farmers' varieties. Indian Basmati was crossed with semi-dwarf varieties and claimed as an invention or a novelty.

It caused a brief diplomatic crisis between India and United States with India threatening to take the matter to WTO (World Trade Organisation) as a violation of TRIPS (Trade Related Aspects of Intellectual Property Rights). Both voluntarily and due to review decisions by United States patent office, Rice Tec lost most of the claims of the patent.

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Q24. The source of Taq polymerase used in PCR technique is a

1. Mesophilic fungus
2. Thermophilic fungus
3. Thermophilic bacteria
4. Halophilic bacteria

Answer: (c)

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Q25. Which one of the following is now being commercially produced by biotechnological procedures?

1. Quinine
2. Morphine
3. Nicotine
4. Insulin

Answer: (d)

Insulin is now being commercially produced by genetic engineering. Insulin consists of two short polypeptide chains: chain A and chain B, that are linked together by disulphide bonds. Insulin, in mammal is synthesised as a prohormone which contains an extra stretch called the C-peptide. During maturation this C-peptide is removed. The major problem for production of insulin using rDNA technique was getting insulin assembled in mature form.

This problem was solved in 1988 by Eli Lilly, an American company which prepared functionable insulin from two DNA sequences corresponding to A and B chains of human insulin and introduced them in plasmids of E.coli to produce insulin chains. In this way, chains A and B were produced separately which was extracted and combined by creating disulphide bonds to get human insulin.

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