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Biology MCQs with answers for NEET Transgenic Animals And Ethical Issues

Question 1. Multicellular organisms that carry a specific genetic change in each cell because of an intervention at the embryo level are a

1. Transversion
2. Transition
3. Transgenic
4. Transformant

Answer: 3. Transgenic

A multicellular organism that carries a specific genetic change in each cell because of an intervention at the fertilized egg stage is transgenic.

Question 2. The maximum number of existing transgenic animals is of

1. Fish
2. Mice
3. Cow
4. Pig

Answer: 2. Mice

In the world, a maximum number of existing transgenic animals are mice.

Read And Learn More: NEET Biology Multiple Choice Question And Answers

Question 3. The first transgenic mouse grew twice the normal size after drinking water containing ……….

1. Cu
2. Fe
3. Zn
4. Ra

Answer: 3. Zn

• In 1974, Rudolf Jaenisch created a transgenic mouse by introducing foreign DNA into its embryo, making it the world’s first transgenic animal. When the transgenic mice were a few weeks old, they were given drinking water containing zinc (Zn).
• Mice carrying the transgene grew to twice the size of their litter mates because the metallothionein enhancer sequence stimulated by zinc has increased growth hormone production.

Question 4. The transgenic animals are those which have

1. Foreign RNA in all its cells
2. Foreign dna in some of its cells
3. Foreign dna in all its cells
4. Both (1) and (3)

Answer: 3. Foreign dna in all its cells

Transgenic animals are those which have foreign DNA in all their cells.

Question 5. Transgenesis is useful in which of the following?

1. To understand the development of disease.
2. To test the newly discovered vaccine.
3. To test the safety of chemicals.
4. To understand the mechanism of regulation of genes.

Choose the correct option.

1. Only 1
2. 2 And 3
3. Only 4
4. 1, 2, 3 And 4

Answer: 4. 1, 2, 3 And 4

All the given statements are useful in transgenesis. Thus, option (4) is correct.

Biology MCQs with answers for NEET

Question 6. Transgenic animals are produced by injecting foreign genes into the

1. Egg
2. The nucleus of an unfertilized egg
3. The nucleus of a fertilized egg
4. Nucleus of sperm

Answer: 3. Nucleus of fertilized egg

Transgenic animals are produced by injecting a foreign gene into the nucleus of a fertilized egg. This fertilized egg divides mitotically to form the whole organism so that all the cells of the organism will carry the transferred gene. The transferred genes are known as transgenes.

Question 7. The introduction of transgenes will result in

1. The formation of a new species
2. The formation of a new protein
3. Altering a biosynthetic pathway
4. Both (2) and (3)

Answer: 4. Both (2) and (3)

The introduction of transgenes will result in the formation of a new protein and the altering of a biosynthetic
pathway. Thus, option (4) is correct.

Question 8. Which transgenic animal is the polio vaccine tested on for safety purposes before administering to humans?

1. Transgenic cow
2. Transgenic monkey
3. Transgenic mice
4. Transgenic sheep

Answer: 3. Transgenic mice

Transgenic mice are developed to test the safety of the polio vaccine before being used on humans.

Biology MCQs with answers for NEET

Question 9. Mice are the preferred choice for transgenesis because

1. They have a short generation time
2. A superovulated mouse can yield up to 40 eggs
3. Reimplantation is relatively easy
4. All of the above

Answer: 4. All of the above

All given options are the preferred choice for transgenesis in mice. Thus, option (4) is correct.

Question 10. The giant mouse is produced by

1. Gene manipulation
2. Gene cloning
3. Gene mutation
4. Gene duplication

Answer: 1. Gene manipulation

• The first example of foreign transfer into an animal by rDNA was the insertion and expression of a rat gene, the Metallothionein (MT) gene for growth hormone in mice.
• It resulted in larger progeny than the parents and the transgenic mouse was called a ‘super (giant) mouse’. So, the giant mouse is produced by gene manipulation.

Question 11. ‘Rosie’ a transgenic animal is known to produce a type of milk which

1. Has a protein content of 2.4 g/l.
2. Has human α-lactalbumin.
3. Is more nutritionally balanced for human babies than natural cow milk.

Which of the above statements is correct?

1. 1 And 2
2. 1 And 3
3. 2 And 3
4. 1, 2 And 3

Answer: 4. 1, 2 And 3

All given statements are correct. In 1997, the first transgenic cow, Rosie produced human protein-enriched milk (2.4 g/L). The milk contained the human α-lactalbumin and was more nutritionally balanced for human babies than natural cow milk. Thus, option (4) is correct.

Biology MCQ For NEET With Answers

Question 12. Which gene was introduced in the first transgenic cow?

1. Human α-lactalbumin
2. Β-1-antitrypsin
3. Α-1-antitrypsin
4. Cryl ac

Answer: 1. Human α-lactalbumin

The gene for human alpha (α) lactalbumin was introduced into the genes of the first transgenic cow, which made the milk nutritionally richer.

Question 13. Consider the following statements about ‘Rosie’.

1. Rosie is the first transgenic sheep.
2. Rosie produced human protein-enriched milk.
3. The milk contained the human α-lactalbumin and scientist behind the research believes that the milk from the cow could provide an alternative to human breast milk.

Which of the statements given above is correct?

1. 1 And 2
2. 1 And 3
3. 2 And 3
4. 1, 2 And 3

Answer: 3. 2 And 3

Statements 2 and 3 are correct whereas statement I is incorrect because. Rosie is a transgenic cow, not sheep.

Question 14. Transgenic animals are produced for

1. To study normal physiology and development.
2. To study diseases.
3. To obtain useful biological products.
4. To test the vaccine safety.
5. To test the chemical safety.

Which of the above statements is correct?

1. 1, 2 And 3
2. 2, 3 And 4
3. 1, 2, 3 And 5
4. 1, 2, 3, 4 And 5

Answer: 4. 1, 2, 3, 4 And 5

(4) All given statements are correct.

Biology MCQ For NEET With Answers

Question 15. Which property of transgenic animals is used in chemical safety testing?

1. Insensitivity to toxic substances
2. Sensitivity to a toxic substance
3. Resistance to a toxic substance
4. Both (1) and (3)

Answer: 2. Sensitivity to a toxic substance

The property of sensitivity to toxic substances is used in chemical safety testing. Transgenic animals are useful as disease models and producers of substances for human welfare.

Question 16. In transgenics, the expression of the transgene in the target tissue is determined by

1. Enhancer
2. Trans gene
3. Promoter
4. Reporter

Answer: 4. Reporter

When plant cells are transformed by any of the transformation methods, it is necessary to isolate the transformed cells/tissue. There are certain selectable marker genes present in vectors that facilitate the selection process. These marker genes are reporter genes.

Question 17. Today, transgenic models have been developed to cure many human diseases, such as

1. Rheumatoid arthritis
2. Alzheimer’s disease
3. Cancer
4. Cystic fibrosis

Choose the correct option.

1. 1 And 2
2. 2 And 4
3. 1, 2 And 4
4. 1, 2, 3 And 4

Answer: 4. 1, 2, 3 And 4

Transgenic models have been developed for many human diseases like cancer, cystic fibrosis, rheumatoid arthritis, and Alzheimer’s disease. Thus, option (4) is correct.

Biology MCQ For NEET With Answers

Question 18. Consider the following statements.

1. Transgenic animals are more sensitive to toxic substances than non-transgenic animals.
2. Useful biological products can be produced by introducing a portion of dna into transgenic animals which codes for a particular product.
3. Brazzein is a protein produced by a West African plant, pentadiplandra brazen which is approximately 2000 times as sweet as sugar.

Which of the statements given above is correct?

1. 1, 2 And 3
2. 1 And 2
3. 1 And 3
4. None of these

Answer: 1. 1, 2 And 3

All given statements are correct.

• Transgenic animals are made to carry genes that make them more sensitive to toxic substances than non-transgenic animals.
• Useful biological products can be produced by introducing the portion of DNA (genes) into transgenic animals which code for a particular product, for example. human protein (α-1-antitrypsin) is used to treat emphysema.
• Brazzein is a protein produced by a West African plant, Pentadiplandra brazen, which is approximately 2000 times as sweet as sugar. It is used as a low-calorie sweetener.

Thus, option (1) is correct.

Question 19. A regulatory body working under Moef for the release of transgenic crops is

1. Nbpgr
2. Geac
3. Nsc
4. Nipgr

Answer: 2. Geac

GEAC is the regulatory body working under MOEF for the release of transgenic crops, i.e. GEAC–Genetic Engineering Approval Committee MOEF–Ministry of Environment and Forest

Question 20. In India, research in genetic modification of organisms and safety issues are controlled by

1. Debt
2. Cari
3. Csir
4. Geac

Answer: 4. Geac

In India, research in genetic modification of organisms and safety issues are controlled by GEAC.

Question 21. Which step has been taken by the government of India to cater to the requirements of patent terms and other emergency provisions in this regard?

1. Passing the biopiracy act
2. Passing the Indian patents bill
3. Forming the gear
4. Passing the bioethics act

Answer: 2. Passing the Indian patents bill

Some nations are developing laws to prevent unauthorized exploitation of their bioresearch and traditional knowledge. To check these problems, the Indian parliament has recently cleared the second amendment of the Indian Patents Bill that takes such issues into consideration.

NEET Biology Mcq

Question 22. The laws and rules to prevent una

1. Biopatenting
2. Bioethics
3. Bioengineering
4. Biopiracy

Answer: 1. Biopatenting

A monopoly granted to a person who has either invented a new and useful article made improvements in an existing article, or invented a new process of making an article is called biopatent. It prevents unauthorized exploitation of bioresources.

Question 23. Which of the following statements about biopatents is/are correct?

1. Biopatents protect the intellectual property rights of an inventor.
2. Biopatents of all products are subjected to commercialization.
3. Biopatents should be granted carefully and impartially.
4. Biopatenting requires the examination of legal, ethical, and social issues.

Choose the correct option.

1. Only 2
2. 1, 3 And 4
3. 2 And 4
4. 1, 2, 3 And 4

Answer: 2. 1, 3 And 4

All given statements are correct about biopatents except 2. Biopatent is a patent granted by the government to the inventor for biological entities and for products obtained from them. These are not always for commercialization, but some are for scientific research benefits.

Question 24. Consider the following statements about the responsibility of geac.

1. Geac takes decisions regarding the validity of the gm research.
2. It checks the safety of introducing gm organisms to public services for their large-scale use.

Choose the correct option.

1. Statement 1 is correct, but 2 is incorrect
2. Statement 1 is incorrect, but 2 is correct
3. Both statements 1 and 2 are correct
4. Both statements 1 and 2 are incorrect

Answer: 3. Both statements 1 and 2 are correct

The aim and objectives of GEAC are

• To permit the use of GM organisms and their products for commercial applications.
• To adopt the procedures for restriction, production scale, import, export, and application of GM organisms.
• Approval to conduct large-scale field trials and release of transgenic crops in the environment.
• To authorize agencies or persons to have large-scale production and the release of GM organisms into the environment or curb and take punitive action against them.

Question 25. Which variety of rice was patented by our company even though the highest number of varieties of this rice is found in India?

1. Basmati
2. Parmal
3. Lerma roja
4. Co-668

Answer: 1. Basmati

Basmati rice is distinct for its aroma and flavour and 27 documented varieties of Basmati are grown in India. In 1997, an American company obtained 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.

NEET Biology Mcq

Question 26. Biopatent means

1. Right to use an invention
2. Right to use biological resources
3. Right to use applications
4. Both (2) and (3)

Answer: 1. Right to use an invention

Biopatent is government protection for an inventor of biological material, securing to him for a specific time the exclusive right of manufacturing, exploiting, using, and selling an invention.

Question 27. Biopatent can be awarded for

1. Strains of microorganisms, cell lines, genetically modified organisms
2. Dna sequences and proteins encoded by them
3. Biotechnological procedures, processes, products, and product applications
4. All of the above

Answer: 4. All of the above

A biopatent is a patent granted by the government to the inventor for biological entities, processes, and products. A patent gives the owner exclusive rights to use the resource, process, or market the product and earn profits. Thus, option (4) is correct.

Question 28. …A… varieties of basmati rice, known for its aroma and flavor, are cultivated in …b….

1. A-27, b-America
2. A-30, b-America
3. A-27, b-india
4. A-30, b-india

Answer: 3. A-27, b-india

Basmati is unique for its aroma and flavor, whose 27 (A) varieties are cultivated in India (B).

Question 29. How many varieties of rice are estimated to be present in India?

1. 2200
2. 20,000
3. 200,000
4. 2000000

Answer: 3. 200,000

Rice is being used for thousands of years in Asia’s agricultural history of which 200,000 varieties are in India alone.

NEET Biology Mcq

Question 30. Choose the correct statements about basmati rice.

1. In 1997, an American company got patent rights for basmati rice through the us patent and trademark office and was allowed to sell a ‘new variety’ in the us and abroad.
2. This new variety of basmati was derived from Chinese farmers’ varieties.
3. Indian basmati was crossed with semidwarf varieties and claimed as an invention or a novelty.

Which of the above statements is correct?

1. 1 And 2
2. 1 And 3
3. 2 And 3
4. 1, 2 And 3

Answer: 2. 1 And 3

All statements are correct except 2. The incorrect statement can be corrected as The new variety of Basmati rice was derived from Indian farmers’ varieties.

Question 31. Which Indian plants have either been patented or attempts have been made to patent them by other nations for their use?

1. Basmati rice
2. Turmeric
3. Neem
4. All of these

Answer: 4. All of these

The patents have been taken out on the plants such as Basmati rice (Oryza sativa), black pepper (Piper nigrum), pomegranate (Punica granatum), Indian mustard (Brassica campestris), turmeric (Curcuma longa) and neem (Azadirachta India). US, Japanese and German companies are the principal patenting pirates.

Thus, option (4) is correct.

Question 32. Rules of conduct that are used to regulate activities with respect to the biological world are called

1. Bioethics
2. Bioware
3. Biopiracy
4. Biopatent

Answer: 1. Bioethics

Rules of conduct that may be used to regulate our activities in relation to the biological world are called bioethics.

Question 33. The use of bioresources by multinational companies and organizations without authorization from the concerned country and its people is called

1. Bioinfringement
2. Bioexploitation
3. Biodegradation
4. Biopiracy

Answer: 4. Biopiracy

Biopiracy is the term used for the unlawful exploitation of bioresources by multinational companies and othe organizations without proper authorization from the countries and people concerned with compensatory payment.

Question 34. Which of the following statement(s) is true?

1. Bioware is the use of biological weapons against humans, crops, and animals.
2. Bioethics is the unauthorized use of bioresources and traditional knowledge related to bioresources for commercial benefits.
3. Biopatent is the exploitation of bioresources from other nations without proper authorization.

Choose the correct option.

1. Only 2
2. Only 1
3. 1 And 2
4. 1 And 3
5. 2 and 3

Answer: 2. Only 1

Statement 1 is true whereas statements 2 and 3 are false. Incorrect statements can be corrected as

• Rules of conduct that may be used to regulate our activities in relation to the biological world are called bioethics.
• A patent is a right granted by the government to an inventor to prevent others to make commercial use of one’s invention. It is known as biopatent.

Question 35. Match the following columns.

Answer: 1. A–4, B–3, C–2, D–1

Question 36. Which of the following has been covered under the broad patent category?

1. Triticum
2. Oryza
3. Pisum sativum
4. Brassica

Answer: 2. Oryza

Oryza has been covered under the broad patent category.

Question 37. The most widely used bioweapon is

1. Bacillus subtilis
2. Pseudomonas putida
3. Bacillus anthracis
4. None of the above

Answer: 3. Bacillus anthracis

• Biowar or biological war is the misuse of biological organisms (bioweapons) against human or their crops and animals, for example.
• In World War-I, Germany used anthrax and bacterial diseases to infect sheep. Bioterrorism occurred in the USA in 2000 through the use of spores of the anthrax bacterium, Bacillus anthracis.

NEET Biology Mcqs – Biotechnological Applications In Medicine

Question 1. Maximum utilisation of biotechnological techniques is made in the field of

1. Chemical industries
2. Medicines
3. Agriculture
4. Biogas production

Answer: 2. Medicines

Biotechnology has helped maximum in the field of medicine, for example, the preparation of monoclonal antibodies, interferon, insulin and drug.

Read And Learn More: NEET Biology Multiple Choice Question And Answers

Question 2. Which of the following products is obtained by genetic engineering?

1. Lactic acid
2. Alcohol
3. Insulin
4. None of these

Answer: 3. Insulin

Out of the given options, insulin is obtained by genetic engineering. This genetically engineered insulin or humulin is produced by inserting a human insulin gene into a plasmid isolated from the E. coli bacterium and then the production of a number of copies or clones of that recombinant gene into another E. coli bacterium.

Question 3. Genetically engineered human insulin is prepared by using

1. E. Coli
2. Rhizopus
3. Pseudomonas
4. Yeast

Answer: 1. E. Coli

By using genetic engineering or recombinant DNA technology, insulin-producing genes from human beings have been transferred into E. coli bacteria, which produced insulin called ‘humulin’ for clinical use. So, genetically engineered human insulin is prepared by using E.coli

Biology MCQ For NEET With Answers

Question 4. Insulin obtained from genetically engineered organisms is more useful because

1. It provides an unlimited quantity of insulin
2. It eliminates the transmission of animal disease through insulin
3. Both (1) and (2)
4. It is produced through an advanced technique

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

Insulin obtained from genetically engineered organisms is more useful because it provides an unlimited quantity of insulin at a time without the risk of transmission of animal diseases through insulin. Thus, option (3) is correct

Question 5. The gene for insulin synthesis is present on

1. 10Th chromosome
2. 11Th chromosome
3. 6Th chromosome
4. 8Th chromosome

Answer: 2. 11Th chromosome

The insulin gene is present on the short arm of chromosome 11 in humans.

Question 6. Insulin is formed of

1. Only a chain
2. Only b chain
3. Only c chain
4. Both (1) and (2)

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

Insulin contains two short polypeptide chains, i.e. A and B chains which are linked by a disulphide bridge. Thus, option (4) is correct.

Question 7. Which of the following statements is not correct?

1. The proinsulin has an extra peptide called c-peptide
2. Functional insulin has a and b chains linked together by hydrogen bonds
3. Genetically engineered insulin is produced in e.coli
4. In man, insulins synthesised as a proinsulin

Answer: 2. The functional insulin has a and b chains linked together by hydrogen bonds

• The statement in option (2) is incorrect because Insulin is composed of two peptide chains referred to as the A chain and B chain.
• A and B chains are linked together by two disulphide bonds, and an additional disulphide is formed within the A chain. Insulin molecules have a tendency to form dimers in solution due to hydrogen bonding between the C-termini of B chains.

Question 8. Maturation of insulin involves the removal of

1. A-chain (21 amino acids)
2. B-chain (30 amino acids)
3. C-chain (33 amino acids)
4. A and b chains

Answer: 3. C-chain (33 amino acids)

• Insulin contains two short polypeptide chains, A and B chains which are linked by a disulphide bridge. In mammals, insulin is synthesised as a prohormone (that needs to be processed to become a mature and functional hormone).
• It contains an extra stretch called C-peptide of 33 amino acids. It is absent in mature insulin and is removed during the maturation of insulin.

Biology MCQ For NEET With Answers

Question 9. The proinsulin is treated with ………… And …………… To obtain the final insulin product.

1. Cyanogen bromide, carboxy ligase
2. Cyanogen trypsin, carboxypeptidase
3. Ethyl bromide, hydroxy ligase
4. Methyl trypsin, carboxy ligase

Answer: 2. Cyanogen trypsin, carboxypeptidase

The proinsulin is treated with cyanogen trypsin and carboxypeptidase to obtain the final insulin product. MetLys human proinsulin could be converted in vitro with the treatment of trypsin and CPB.

Question 10. ….. A……… And ……b……. Are present at the n and c-terminal of b- a chain of insulin.

1. A–phenylalanine, b–alanine
2. A–glycine, b–asparagine
3. A–leucine, b–isoleucine
4. A–methionine, b–tryptophan

Answer: 1. A–phenylalanine, b–alanine

Phenylalanine (1) and alanine (2) are present at the N and C-terminal of the B-chain of insulin.

Question 11. During the synthesis of insulin, proinsulin is linked to the lac operon with

1. Lactosidase gene
2. Permease gene
3. Galactosidase gene
4. All of the above

Answer: 3. Galactosidase gene

Proinsulin is linked to the lac operon with the galactosidase gene during the synthesis of insulin.

Question 12. The primary structure of insulin was given by

1. Frederick sanger
2. Banting
3. Macleod Eli Lilly
4. William Bateson

Answer: 1. Frederick Sanger

In 1954, Frederick Sanger derived the complete structure of bovine insulin.

Biology MCQ For NEET With Answers

Question 13. A step in the rDNA technology that was crucial in the production of human insulin was

1. Splitting a and b-peptide chain
2. Addition of c-peptide to proinsulin
3. Getting insulin assembled into the mature form
4. Removal of c-peptide from active insulin

Answer: 3. Getting insulin assembled into the mature form

The main challenge for the production of insulin using the rDNA technique was obtaining insulin in a mature form. In 1983, Eli Lilly, an American company, first prepared two DNA sequences corresponding to the A and B chains of human insulin and introduced them into the plasmids of Escherichia coli to produce insulin chains separately.

Question 14. Identify the diagram that shows the maturation of proinsulin to insulin.

Answer: 1. Diagram (1) correctly represent the maturation of proinsulin into insulin after the removal of the C-peptide.

Question 15. Which method is used to prepare cDNA in insulin preparation?

1. Transcription
2. Reverse transcription
3. Replication
4. Duplication

Answer: 2. Reverse transcription

Reverse transcriptase is used to create cDNA libraries from mRNA. Thus, reverse transcription is used to prepare cDNA in insulin preparation.

Question 16. Which of the following statements is incorrect?

1. Insulin used to be extracted from the pancreas of slaughtered pigs and cattle.
2. Animal insulin is slightly different from the human insulin.
3. Animal insulin causes some undesirable side effects such as allergy.
4. Bacteria can be made to synthesise insulin from its gene even with the presence of introns.

Choose the correct option.

1. Only 1
2. 1, 3 And 4
3. 1, 2, 3 And 4
4. Only 4

Answer: 4. Only 4

Statement IV is incorrect. It can be corrected When using bacteria to clone a human gene and express its products as in the case of insulin, the gene cannot contain introns because bacteria do not have the enzymes to process mRNA.

Biology MCQ For NEET With Answers

Question 17. Consider the following statements about insulin.

1. Human insulin is made up of 51 amino acids arranged on two polypeptide chains.
2. The two polypeptide chains are interconnected by three disulphide bonds.
3. In mammals, insulin is synthesised as a prohormone which contains an extra chain called c-peptide.
4. C-peptide is not present in mature insulin.

Which of the statements given above is correct?

1. 1, 2 And 3
2. 1, 3 And 4
3. 2, 3 And 4
4. 1, 2, 3 And 4

Answer: 2. 1, 3 And 4

All given statements are correct about insulin, except II because Human insulin is made up of 51 amino acids arranged on two polypeptide chains. A has 21 amino acids and B with 30 amino acids, the two polypeptide chains are interconnected by two disulphide bridges or S-S linkages.

Question 18. The first step in the production of insulin using e.coli is

1. Isolation of mRNA transcribing for insulin from pancreas cell
2. Isolation of nucleotides transcribing for insulin from pancreas cell
3. Isolation of gene-producing insulin from human DNA
4. Attachment of gene-producing insulin from human dna to plasmid using ligase

Answer: 3. Isolation of gene-producing insulin from human DNA

Question 19. Genetically engineered human insulin, humulin was launched by an American drug company on

1. 5Th July 1998
2. 5Th July 1993
3. 5Th July 1973
4. 5Th July 1983

Answer: 4. 5Th July 1983

On 5th July 1983, Eli Lilly Company launched the first genetically engineered human insulin by the name of humulin.

Question 20. Assertion humulin is better than conventional insulin. Reason (R) Conventional insulin produces many side effects.

1. Both A and R are true and R is the correct explanation of a
2. Both A and R are true, but R is not the correct explanation of A
3. A is true, but R is false
4. Both A and R are false

Answer: 1. Both A and R are true and R is the correct explanation of A

Both A and R are true and R is the correct explanation of A. Humulin is the first genetically engineered pharmaceutical product. It is better than conventional insulin because conventional insulin produces many side effects over a long period.

NEET Biology Mcq

Question 21. In 1921, two Canadian scientists, Frederick G. Banting and Charles H. Best successfully purified insulin from a

1. Pig’s pancreas
2. Camel’s pancreas
3. Dog’s pancreas
4. Cattle’s pancreas

Answer: 3. Dog’s pancreas

• Frederick Banting and Charles Best discovered insulin under the directorship of John Macleod at the University of Toronto.
• With the help of James Collip insulin was purified from a dog’s pancreas, making it available for the successful treatment of diabetes. Banting and Macleod earned Nobel Prize for their work in 1923.

Question 22. Lymphocytes are

1. A kind of white blood cells
2. A kind of red blood cells
3. Blood platelets
4. Plasma and white blood cells

Answer: 1. A kind of white blood cells

A lymphocyte is a kind of WBCs in the vertebrate immune system. The three major types of lymphocytes are T-cells, B-cells and Natural Killer (NK) cells.

Question 23. Gene therapy

1. Aims to cure genetic disorders
2. Is a method to provide the correct version of the defective gene
3. Include enzymatic replacement therapy
4. All of the above

Answer: 4. All of the above

• Gene therapy is a collection of methods that allows the correction of gene defects diagnosed in a child or embryo. It aims to cure genetic disorders.
• It involves the insertion of normal genes and the defective mutant allele of the genes is replaced and the non-functional gene is compensated. It also employs the use of enzyme replacement therapy. Thus, option (d) is correct.

Question 24. In somatic cell gene therapy, the desirable gene is introduced

1. Into sperms
2. Into eggs
3. Into blood cells
4. Into zygote

Answer: 3. Into blood cells

In somatic cell gene therapy, the desirable gene is introduced into any cell other than a gamete, germ cell or stem cell. The changes that are observed are only restricted to the individual and are not carried to the next generation. Thus, the gene is introduced into blood cells in somatic cell gene therapy.

Question 25. A young girl was treated for a deficiency that occurs due to a genetic disorder. M Blease and wf Andresco made use of gene therapy to correct this disorder. Identify it.

1. Cytosine deaminase (cda) –scid
2. Adenosine deaminase (ada)–scid
3. Tyrosine oxidase –scid
4. None of the above

Answer: 2. Adenosine deaminase (ada)–scid

For the first time in 1990, M Blease and WF Andresco attempted gene therapy on a 4-year-old girl with Adenosine Deaminase (ADA) deficiency. This is caused due to the deletion of a gene for adenosine deaminase.

NEET Biology Mcq

Question 26. Where is ada produced in the human body?

1. Bone marrow
2. Lymphocytes
3. Blood plasma
4. Monocytes

Answer: 2. Lymphocytes

The site of production of Adenosine Deaminase (ADA) in the human body is lymphocytes.

Question 27. A person suffering from scid has a defective gene for the enzyme adenosine deaminase (ADA). As a result of which the person lacks ……………… Thus making him prone to infections.

1. B-lymphocytes
2. Phagocytes
3. T-lymphocytes
4. Both (1) and (2)

Answer: 3. T-lymphocytes

Patients suffering from SCID have defective genes for the enzyme Adenosine Deaminase (ADA). Functional T-lymphocytes are missing thus, making them prone to infections.

Question 28. In the treatment of SCID, cDNA is introduced into a patient’s cells using …………………. As a vector.

1. E. Coli
2. Retrovirus
3. Bacillus thuringiensis
4. Agrobacterium

Answer: 2. Retrovirus

• A functional ADA cDNA can be introduced into the cells of the patients receiving gene therapy by using a vector constituted by a retrovirus.
• The SCID patient has a defective gene for the enzyme, Adenosine Deaminase (ADA). He/she lacks functional T-lymphocytes and therefore, fails to fight the infecting pathogen.
• Lymphocytes are extracted from the patient’s bone marrow and a normal functional copy of human gene coding for ADA is introduced into these lymphocytes with the help of retrovirus.

Question 29. Which one of the following vectors is used to replace the defective gene in gene therapy?

1. Ti plasmid
2. Adenovirus
3. Cosmid
4. Ri plasmid

Answer: 2. Adenovirus

Adenovirus vectors can be replication defective, certain essential viral genes are deleted and replaced by a cassette that expresses a foreign therapeutic gene. Such vectors are used for gene therapy as vaccines and for cancer therapy.

NEET Biology Mcq

Question 30. Adenosine deaminase (ADA) deficiency can be cured by …………… And ……………….

1. Gene therapy, radiation therapy
2. Bone marrow transplantation, enzyme replacement therapy
3. Organ transplantation, hormone replacement therapy
4. Radiation therapy, enzyme replacement therapy

Answer: 2. Bone marrow transplantation, enzyme replacement therapy

In some cases, adenosine deaminase deficiency can be cured by bone marrow transplantation and enzyme replacement therapy, but it is not fully curative.

Question 31. What might be an advantage of beginning gene therapy prior to birth?

1. This would give the body plenty of time
2. The body would not reject it as it has not yet recognised ‘self’
3. The cells being extremely young are more receptive to gene therapy
4. None of the above

Answer: 2. The body would not reject it as it has not yet recognised the ‘self’

Gene therapy can be initiated prior to birth too. An advantage of this technique is that the body would not reject it as it has to yet recognise itself.

Question 32. The genetic defect adenosine deaminase (ADA) deficiency may be cured permanently by

1. Introducing bone marrow cells producing ada into cells at early embryonic stages
2. Enzyme replacement therapy
3. Periodic infusion of genetically engineered lymphocytes having functional ada cdna
4. Administering adenosine deaminase activators

Answer: 1. Introducing bone marrow cells producing ada into cells at early embryonic stages

By introducing bone marrow cells producing ADA into cells at early embryonic stages, Adenosine Deaminase (ADA) deficiency may be cured permanently.

Question 33. Arrange the following steps occurring during gene therapy in chronological order.

1. Lymphocytes are obtained from the patients.
2. Lymphocytes are transferred to the culture dishes.
3. Lymphocytes are transfected with the normal ADA genes.
4. The transfected cell is returned to the patient’s body.

The chronological order should be

1. 1 → 2 → 3 → 4
2. 2 → 1 → 3 → 4
3. 1 → 3 → 2 → 4
4. 3 → 2 → 4 → 1

Answer: 1. 1 → 2 → 3 → 4

NEET Biology Mcq Chapter Wise

Question 34. The assertion the ada gene provides instruction for producing the enzyme, adenosine deaminase. Reason (R) This enzyme is found throughout the body but is most active in lymphocytes.

1. Both A and R are true and R is the correct explanation of A
2. Both A and R are true, but R is not the correct explanation of A
3. A is true, but R is false
4. Both A and R are false

Answer: 2. Both A and R are true, but R is not the correct explanation of A

• Both A and R are true, but R is not the correct explanation of A. The ADA gene provides instructions for producing the enzyme, adenosine deaminase.
• This enzyme is produced in all cells, but the highest levels of adenosine deaminase occur in immune system cells called lymphocytes. In the absence of adenosine deaminase enzyme, purine metabolism is disturbed and T-lymphocytes fail to function.

Question 35. What is true for monoclonal antibodies?

1. These antibodies obtained from one parent and for one antigen
2. These antibodies were obtained from the parent and for two antigens
3. These antibodies obtained from one parent and for many antigens
4. These antibodies are obtained from many parents and for many antigens

Answer: 1. These antibodies are obtained from one parent and for one antigen

(1) Option (1) is true for monoclonal antibodies as Monoclonal antibodies are identical molecules specific for one type of antigen. These are obtained from one parent by injecting the target antigen into a rat or mouse.

Question 36. The assertion the term hybridoma is applied to fused cells. Reason (R) they are formed by the fusion of lymphocyte cells and myeloma cells.

1. Both A and R are true and R is the correct explanation of a
2. Both A and R are true, but R is not the correct explanation of A
3. A is true, but R is false
4. Both A and R are false

Answer: 1. Both A and R are true and R is the correct explanation of a

Both A and R are true and R is the correct explanation of A. Hybridoma technology is a technology of the formation of hybrid cell lines, i.e. hybridomas by the fusion of a B-lymphocyte cell and a myeloma cell. The hybrid cell produced is selected on the basis of its ability to grow in tissue culture.

NEET Biology Mcq Chapter Wise

Question 37. Hybridomas are the result of the fusion of

1. Normal antibody-producing cell with a myeloma
2. Abnormal antibody-producing cell with myeloma
3. Male reproductive cell with a myeloma
4. Female reproductive cells with myeloma

Answer: 1. Normal antibody-producing cell with myeloma

Hybridomas are hybrid cells resulting from the fusion of a normal antibody-producing B-lymphocyte and a multiple myeloma cell from the lymphoid tumour. This hybrid cell is capable of producing a continuous supply of antibodies.

Question 38. Consider the following statements.

1. Hybridoma cells are shifted to a medium deficient in nutrients which cannot be synthesised by myeloma cells.
2. This medium allows the selection of hybridoma cells.

Choose the correct option.

1. Statement 1 is correct, but 2 is incorrect
2. Statement 1 is incorrect, but 2 is correct
3. Both statements 1 and 2 are correct.
4. Both statements 1 and 2 are incorrect

Answer: 3. Both statements 1 and 2 are correct.

Question 39. Elisa is based on

1. Antigen-antibody interaction
2. Antigen-protein interaction
3. Lectin-antibody interaction
4. All of the above

Answer: 1. Antigen-antibody interaction

ELISA is based on the principle of antigen-antibody interaction. It can detect very small amounts of proteins (antibody or antigen) with the help of enzymes (for example peroxidase or alkaline phosphatase).

NEET Biology Mcq Chapter Wise

Question 40. How many antibodies are used in Elisa?

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

Answer: 1. 2

Performing ELISA involves one antibody with specificity to a particular antigen. After the antigen is immobilised, the second detection antibody is added which is also called a secondary antibody. It is linked to an enzyme through bioconjugation. So, two antibodies are used in ELISA.

Question 41. Elisa is used to detecting viruses where the key reagent is

1. Rnase
2. Alkaline phosphatase
3. Catalase
4. Dna probe

Answer: 2. Alkaline phosphatase

ELISA test is a technique which can detect any amount of an antibody or antigen with the help of an enzyme. The commonly used enzymes are alkaline phosphatase and peroxidase.

Question 42. Identify the molecular diagnostic technique used to detect the presence of a pathogen in an early stage of infection.

1. Polymerase chain reaction (PCR)
2. Radiography
3. Enzyme replacement technique
4. Angiography

Answer: 1. Polymerase chain reaction (PCR)

• The presence of a pathogen (bacteria, viruses, etc.) is usually suspected only when the pathogen has produced a diseased symptom.
• By that time, the number of pathogens is already very high in the body but the very low count of bacteria or viruses (when the symptoms of the disease are not yet visible) can be detected by multiplication of their nucleic acid by PCR.

NEET Biology Mcq Chapter Wise

Question 43. Which of the following is a recent application of genetic engineering in diagnostic techniques?

1. Pcr
2. Abc blood groups
3. Elisa test
4. Gravidax test

Answer: 1. Pcr

The historical development of techniques for altering genetic information on the molecular level can be included in Polymerase Chain Reaction (PCR) based gene manipulation. Genetic engineering with PCR forms powerful methods for assembling designer genes.

Question 44. A single strand of nucleic acid tagged with a radioactive molecule is called

1. Plasmid
2. Recombinant dna
3. Probe
4. Selectable marker

Answer: 3. Probe

Molecular probes are usually single-stranded pieces of DNA (sometimes RNAs), labelled with radioisotopes such as 32 P. They are available for many genetic disorders such as Duchenne muscular dystrophy, cystic fibrosis, Tay-Sachs disease, etc.

Question 45. A novel use of PCR is to

1. Detect hiv in suspected aids patients
2. Detect mutations in suspected cancer patients
3. Diagnose many genetic disorders
4. All of the above

Answer: 4. All of the above

PCR can detect very low amounts of DNA. It is now usually used to detect HIV in suspected AIDS patients. It is also used to detect mutations in the genes in suspected cancer patients. It is a good technique to identify many other genetic disorders. Thus, option (4) is correct.

Question 46. A doctor while performing surgery on an HIV (+) patient accidentally cut himself with a scalpel. A test that he will have to undergo in order to verify or rule out the suspicion of infection from the HIV virus is

1. Pcr
2. Routine urine examination
3. Tlc
4. Dec

Answer: 1. Pcr

PCR is now, used to detect HIV in suspected AIDS patients.

Question 47. In which method, is a probe allowed to hybridise to its complementary dna in the clone of cells?

1. Gene therapy
2. Recombinant dna technology
3. Polymerase chain reaction
4. None of the above

Answer: 2. Recombinant dna technology

• In recombinant DNA technology, a probe is allowed to hybridise with its complementary DNA in the clone of cells. The cells are then detected by autoradiography.
• The cells with mutated genes will not be observed on the photographic film because the probe was not complementary to the mutated genes.

Question 48. Protein-protein hybridisation results in

1. Southern blotting
2. Northern blotting
3. Western blotting
4. None of the above

Answer: 3. Western blotting

The Western blot is an analytical technique used to detect specific proteins in a sample of tissue homogenate or extract. It is used to detect the particular protein in a protein mixture. So, protein-protein hybridisation results in Western blotting.

NEET Biology Mcq Chapter Wise

Question 49. The technique used to detect the dna in a clone is called

1. Gel electrophoresis
2. Autoradiography
3. Gene therapy
4. None of the above

Answer: 2. Autoradiography

A single-stranded DNA or RNA joined with a radioactive molecule (probe) is allowed to hybridise with its complementary DNA in a clone of the cells in recombinant DNA technology. It is followed by the detection of DNA using autoradiography.

Question 50. Which one of the following is the correct explanation for autoradiography?

1. It is used for the detection of mutated genes
2. Clone which has mutated genes do not appear on the photographic film
3. The probe has only complementary genes with unmuted protein of dna
4. All of the above

Answer: 3. The probe has only complementary genes with unmuted protein of DNA

All given explanations are correct for autoradiography. Thus, option (4) is correct.

Question 51. Choose the correct option for the use of the PCR technique in diagnosis.

1. It is used to detect HIV in suspected aids patients.
2. It is used to detect mutations in the genes in suspected cancer patients.
3. It is used to detect swine flu in human beings.
4. It is used to detect different common diseases in pigs, sheep and cows.
5. It is a good technique to identify many other genetic disorders.

Which of the above statements is correct?

1. 1 And 2
2. 3 And 4
3. 1, 2 And 5
4. 2, 3 And 4

Answer: 3. 1, 2 And 5

• Statements 1, 2 and 5 are correct for the use of PCR technique in diagnosis. PCR can detect very low amounts of DNA. It is now usually used to detect HIV in suspected AIDS patients. It is also used to detect mutations in the genes in suspected cancer patients.
• It is a good technology to detect many other genetic disorders. Statements 3 and 4 are not correct. PCR is not used to detect common diseases in animals and swine flu in humans.

Question 52. Which of the following techniques are related to gene therapy?

1. Bone marrow transplantation.
2. Enzyme replacement therapy.
3. Pcr
4. Hybridoma technique.

Choose the correct option.

1. 1 And 2
2. 2 And 3
3. 1, 2 And 3
4. 2, 3 And 4

Answer: 1. 1 And 2

Bone marrow transplantation and enzyme replacement therapy are related to gene therapy. PCR is used to obtain copies of normal genes outside the body and then used for gene therapy. The Hybridoma technique is a method of producing identical antibodies in large amounts. Thus, option (1) is correct.

Question 53. Modified antibiotics are manufactured by the technique of

1. Ultrafiltration
2. Ultracentrifuge
3. Vernalisation
4. Genetic engineering

Answer: 4. Genetic engineering

Genetic engineering has produced many modern antibiotics through biotechnology, for example. hybrid antibiotic, i.e. molecules that have bits from two different antibiotics. This is done by putting selected enzymes from two different antibiotic-producing cells into one bacterium.

Question 54. Consider the following statements about therapeutic drugs.

1. Recombinant dna technology is used for the production of safe and effective therapeutic drugs.
2. It avoids unwanted immunological responses, observed with products isolated from non-human sources.
3. About thirty recombinant therapeutics have been approved for human use around the world.

Which of the following statements given above are correct?

1. 1 And 2
2. 1 And 3
3. 2 And 3
4. 1, 2 And 3

Answer: 4. 1, 2 And 3

All given statements are correct about therapeutic drugs. Thus, option (4) is correct.

Question 55. Match the following columns.

Answer: 1. A–1, B–3, C–2, D–4

Question 56. Which of the following techniques are utilised for early diagnosis of aids, cancer, etc?

1. Polymerase chain reaction
2. Recombinant dna technology
3. Enzyme-linked immunosorbent assay

Choose the correct option.

1. 1 And 2
2. 1 And 3
3. 2 And 3
4. 1, 2 And 3

Answer: 4. 1, 2 And 3

All given statements are utilised for early diagnosis of AIDS, cancer, etc. Early detection of a disease is not possible by conventional diagnosis methods. Some techniques used for early diagnosis are

• Polymerase chain reaction
• Recombinant DNA technology
• Enzyme-Linked Immuno-Sorbent Assay (ELISA)

Thus, option (4) is correct.

Question 57. The maximum application of animal cell culture technology today is in the production of

1. Edible proteins
2. Insulin
3. Interferons
4. Vaccines

Answer: 4. Vaccines

The maximum application of animal cell culture technology today is in the production of vaccines.

Question 58. Pure vaccines are

1. Mhc antigens
2. Monoclonal antibodies
3. Bacteria treated fungi
4. Certain proteins

Answer: 2. Monoclonal antibodies

Monoclonal Antibody (MAb) is a homogeneous antibody derived from a single clone of cells. MAb recognises only one chemical structure and is useful in a variety of industrial and medical capacities since it is easily produced in large quantities and has remarkable specificity. Thus, pure vaccines are monoclonal antibodies.

Biotechnological Applications In Agriculture

Question 1. An important objective of biotechnology used in agriculture is

1. To produce pest-resistant varieties of plants
2. To increase the nitrogen content
3. To decrease the seed number
4. To increase the plant weight

Answer: 1. To produce pest-resistant varieties of plants

• An important objective of biotechnology in the agriculture section is to produce pest-resistant varieties of plants.
• This includes plant breeding to raise and stabilise yields, to improve resistance to pests, diseases and abiotic stresses such as drought and cold and to enhance the nutritional content of foods.

Read And Learn More: NEET Biology Multiple Choice Question And Answers

Question 2. The applications of biotechnology involve all except one. Identify it.

1. Waste treatment
2. Energy production
3. Genetically modified crops
4. Conventional hybridisation

Answer: 4. Conventional hybridisation

Biology MCQ For NEET With Answers

The applications of biotechnology involve

• Therapeutics
• Diagnostics
• Genetically modified crops and animals for agriculture
• Processed food
• Bioremediation
• Waste treatment
• Energy production

Conventional hybridisation does not include the application of biotechnology.

Question 3. Agrochemical-based agriculture includes

1. Fertilisers and pesticides
2. Genetically modified crops
3. Rna interference
4. None of the above

Answer: 1. Fertilisers and pesticides

Agrochemical-based agriculture includes fertilisers and pesticides. Agrochemicals are expensive for farmers in developing countries and are used to increase food production.

Question 4. Choose the correct statement about agrochemicals.

1. These are expensive for farmers in developing countries
2. These have harmful effects on the environment
3. Genetically modified crops are less expensive than agrochemicals
4. All of the above

Answer: 4. All of the above

All the given statements are correct as Agrochemicals are expensive for farmers in developing countries and also they have harmful effects on the environment. Therefore, genetically modified crops are well-developed to overcome such problems. Thus, option (4) is correct.

Question 5. Production of value-added products like nutrition supplements, pharmaceuticals, fuels, etc., Using the transgenic crop is called

1. Genetic farming
2. Molecular farming
3. Biotech farming
4. Both (1) and (2)

Answer: 2. Molecular farming

Production of value-added products like nutrition supplements, pharmaceuticals, fuels, etc., using transgenic crops is called molecular farming.

Question 6. Consider the following statements about organic farming.

1. Utilises genetically modified crops like bt cotton.
2. Uses only naturally produced inputs like compost.
3. Does not use pesticides and urea.
4. Produces vegetables rich in vitamins and minerals.

Which of the above statements is correct?

1. 2, 3 And 4
2. 3 And 4
3. 2 And 3
4. 1 And 2

Answer: 3. 2 And 3

• Statements 2 and 3 are correct. Other statements are incorrect and can be corrected as Organic farming does not mean that it uses genetically modified crops or produce vegetables enriched with vitamins and minerals.
• It is a form of agriculture that relies on the techniques like crop rotation, green manure, compost and biological pest control.

Biology MCQ For NEET With Answers

Question 7. An increase in food production is essential to meet the ever-increasing demands of the population. Identify the ways of increasing food production.

1. Agrochemical based agriculture
2. Organic agriculture
3. Genetically engineered crop-based agriculture

Choose the correct option.

1. Only 1
2. 1 And 3
3. 2 And 3
4. 1, 2 And 3

Answer: 4. 1, 2 And 3

All given ways are correct for increasing food production. Food production can be increased by applying biotechnology in the following ways

• Agrochemical based agriculture
• Organic agriculture
• Genetically engineered crop-based agriculture

Thus, option (4) is correct.

Question 8. The name norman borlaug is associated with

1. White revolution
2. Green revolution
3. Yellow revolution
4. Blue revolution

Answer: 2. Green revolution

• The term Green revolution refers to the very significant increase in yield obtained by breeding high-yielding varieties of crops, under intensive application of fertilisers, irrigation and pesticides.
• The worldwide increase in productivity has come to be known as the ‘Green Revolution’ for which Dr Borlaug won the Nobel Peace Prize in 1970.

Question 9. Green Revolution saw success due to

1. The use of improved varieties of crops.
2. The use of agrochemicals.
3. The use of better management practices.

Choose the correct option.

1. 1 And 2
2. 1 And 3
3. 2 And 3
4. 1, 2 And 3

Answer: 4. 1, 2 And 3

Biology MCQ For NEET With Answers

The Green Revolution succeeded in increasing the food supply because of

• Use of improved crop varieties.
• Use of agrochemicals (fertilisers and pesticides).
• Use of better management practices. Thus, option (4) is correct

Question 10. Gm crop is a

1. Infected crop
2. Transgenic crop
3. Raised on green manure
4. A green manure

Answer: 2. Transgenic crop

A popular term for the transgenic crop is Genetically Modified (GM) crops. A transgenic crop is a crop, which contains and expresses a transgene.

Question 11. Plants, bacteria, fungi and animals whose genes have been altered by manipulation are called

1. Genetically modified organisms
2. Hybrid organisms
3. Pest resistant organisms
4. Insect resistant organisms

Answer: 1. Genetically modified organisms

Genes of plants, bacteria, fungi and animals have been changed by manipulations therefore, these organisms are called Genetically Modified Organisms (GMOs). The behaviour of GMOs depends on the nature of genes transferred, and the nature of host plants, bacteria and animals.

Question 12. Transgenic organisms are formed by

1. Crossing two hybrids
2. Inducing mutations by chemicals
3. Introducing foreign genes
4. Crossing genes of somatic cells of the same organisms

Answer: 3. Introducing foreign genes

Transgenic organisms are formed by introducing foreign genes, which are transferred into them through genetic engineering. These genes are known as transgenes.

Question 13. What effect does eating genetically modified foods have on your genes?

1. It could cause your own genes to mutate
2. It could cause your own genes to absorb the excess genes
3. It has no effect so far detected on your genes
4. The effects on human genetics are not known

Answer: 3. It has no effect so far detected on your genes

No allergic effects have been found relative to Genetically Modified (GM) foods currently on the market.

Biology MCQ For NEET With Answers

Question 14. Are foods derived from genetically modified crops nutritionally superior?

1. Yes, they offer substantial health advantages over foods produced from conventional crops
2. Yes, they offer a few health benefits over foods produced from conventional crops
3. No, they are neither better nor worse than foods from conventional crops
4. No, they are slightly less nutritional than foods from conventional crops

Answer: 3. No, they are neither better nor worse than foods from conventional crops

Most of the genetically modified crops currently available are designed to reduce farmers’ production costs. Under some circumstances, there may be fewer pesticides used and there is some indication that genetically modified corn is less likely to be infected with fungal toxins that are natural carcinogens, but the overall health effect of these benefits is minor. So, no, they are neither better nor worse than foods from conventional crops.

Question 15. The main objective of the production/use of herbicide-resistant gm crops is to

1. Eliminate weeds from the fields without any use of manual labour
2. Eliminate weeds from the fields without the use of herbicides
3. Encourage eco-friendly herbicides
4. Reduce herbicide accumulation in food articles for health safety

Answer: 4. Reduce herbicide accumulation in food articles for health safety

• The main objective of the production of herbicide-resistant genetically modified crops is to reduce herbicide accumulation in food articles for health safety.
• Herbicide-resistant plants have been developed in such a way that they continue to produce normal crop yield and at the same time remain unaffected by the activity of herbicides. These plants also reduce the use of weeding labour, farmer’s cost and increase yield.

Question 16. Why should foods derived from genetically modified crops be tested for possible allergic reactions in people?

1. They may cause allergies due to the release of new kinds of proteins
2. They may not be digested
3. They may cause more hunger
4. All of the above

Answer: 1. They may cause allergies due to the release of new kinds of proteins

Scientists have long known that GM crops might cause allergies due to the release of new kinds of proteins. But there are no tests to prove in advance that a GM crop is safe. That is because people are not usually allergic to a food until they have eaten it several times.

Question 17. Assertion transgenic plant is a product of plant tissue culture. Reason (r) it is an organism that contains and expresses a transgenic organism.

1. Both a and r are true and r is the correct explanation of a
2. Both a and r are true, but r is not the correct explanation of a
3. A is true, but r is false
4. Both a and r are false

Answer: 2. Both a and r are true, but r is not the correct explanation of a

• Both A and R are true, but R is not the correct explanation of A. Plant tissue culture has various applications in the different fields of biology.
• An example of this is the production of transgenic plants and animals. Transgenic organisms contain foreign DNA that has been introduced, using biotechnology.

Question 18. Genetically modified plants have been useful in increasing

1. Crop yield
2. Nutritional value of food
3. Tolerance against abiotic stresses
4. All of the above

Answer: 4. All of the above

Biology MCQ For NEET With Answers

Genetic modification of crops has resulted in

• Increased tolerance against abiotic stresses (cold, drought, salt and heat).
• Reduced reliance on chemical pesticides (pest-resistant crops).
• Reduced post-harvest losses.
• Enhanced nutritional value of food, for example. vitamin-A enriched golden rice.
• Increased efficiency of minerals used by the plants (this prevents early exhaustion of fertility of soil).

Increase crop yield. Thus, option (4) is correct.

Question 19. A transgenic food crop which may help in solving the problem of night blindness in developing countries is

1. Bt soybean
2. Golden rice
3. Flavr save tomatoes
4. Starlink maize

Answer: 2. Golden rice

• Golden rice is a transgenic food crop which may help in solving the problem of night blindness in developing countries.
• Golden rice or miracle rice is rich in vitamin-A, β-carotene or iron and decaffeinated coffee is also the valuable achievement of gene transfer technology.

Question 20. Golden rice was created by transforming rice with two β-carotene biosynthesis genes, namely

1. Psy and cry-i genes
2. Lcy-e
3. Chy-1
4. Chy-2

Answer: 1. Psy and cry-i genes

Transgenic golden rice was created by transforming rice with two β-carotene biosynthesis genes, Psy (phytoene synthase) from daffodil (Narcissus pseudonarcissus) and cry I from the soil bacterium Erwinia uredovora.

Question 21. Which of the following is true for golden rice?

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

Answer: 1. It is vitamin-a enriched, with a gene from daffodil

• (1) Option (1) is true for golden rice as Golden rice is vitamin-A enriched, with a gene from daffodil and is rich in β-carotene.
• Transgenic golden rice was created by transforming rice with two β-carotene biosynthesis genes, Psy (phytoene synthase) from daffodil (Narcissus pseudonarcissus) and cry 1 from the soil bacterium Erwinia uredovora.

Question 22. Which of the following statements is incorrect about genetically modified plants?

1. They have improved nutritional quality
2. They are drought and salt resistant
3. They cause loss of fertility of the soil
4. They reduce post-harvest losses

Answer: 3. They cause loss of fertility of the soil

The statement in option (3) is incorrect about genetically modified plants. It can be corrected as Genetically modified plants have enhanced the efficiency of mineral usage to prevent early exhaustion of fertility of the soil. Rest statements are correct about genetically modified plants.

Question 23. Golden rice

1. A transgenic variety of rice.
2. Contains a good quality of βcarotene (provitamin-a).
3. Β-carotene is a principal source of vitamin-a.
4. The grains of the rice are yellow in colour due to β-carotene.
5. The rice is commonly called golden rice.

Which of the statements given above is correct?

1. 1, 2 And 3
2. 2, 3 And 4
3. 1, 3 And 4
4. 1, 2, 3 And 4

Answer: 4. 1, 2, 3 And 4

• All given statements about golden rice are correct as Golden rice is developed at the Swiss Federal Institute of Technology. The rice grains are golden yellow in colour due to the presence of β-carotene (provitamin-A).
• It contains the ‘beta carotene’ gene from daffodil plants and also genes from some bacteria. Golden rice (a transgenic variety of rice) can prevent child blindness caused due to deficiency of vitamin-A.

Biology MCQ For NEET With Answers

Question 24. Which of the following is a transgenic plant?

1. Hirudin
2. Triticale
3. Flavr save
4. All of these

Answer: 3. Flavr save

• A transgenic plant is a plant which contains and expresses a transgene. Among the following, the Flavr Savr tomato plant is a genetically engineered plant.
• This Flavr Savr tomato can remain fresh for a long time than other varieties of tomato. Thus, it has delayed ripening, and a longer shelf-life, without spoiling the flavour.

Question 25. The transgenic plant ‘flavour save tomato’ carries an artificial gene for

1. Delaying ripening process
2. Longer shelf-life
3. Retaining the flavour
4. All of the above

Answer: 4. All of the above

• All statements are correct. A transgenic plant is a plant which contains and expresses a transgene. Among the following, the Flavr Savr tomato plant is a genetically engineered plant.
• This Flavr Savr tomato can remain fresh for a long time than other varieties of tomato. Thus, it has delayed ripening, and a longer shelf-life, without spoiling the flavour.

Question 26. Which enzyme is responsible for the ripening of tomatoes?

1. Α-galactosidase
2. Polygalacturonase
3. Transferase
4. Proteolase

Answer: 2. Polygalacturonase

Polygalacturonase enzyme is responsible for the breakdown of cell wall pectin and is responsible for the ripening of tomatoes.

NEET Biology Mcq Chapter Wise

Question 27. Assertion flavour save, a transgenic tomato which remains fresh and retains its flavour for a long time. Reason (r) production of polygalacturonase enzyme, which degrades pectin, is blocked in flavour save.

1. Both a and r are true and r is the correct explanation of a
2. Both a and r are true, but r is not the correct explanation of a
3. A is true, but r is false
4. Both a and r are false

Answer: 1. Both a and r are true and r is the correct explanation of a

Both A and R are true and R is the correct explanation of A. Flavr Savr is a transgenic tomato variety. Fruits of this variety remain fresh and retain their flavour for much longer than normal fruits. It happens due to the blockage of the production of the pectin-degrading enzyme polygalacturonase.

Question 28. Isolation of gene from bacterium bacillus thuringiensis was taken up in the year

1. 1977
2. 1980
3. 1997
4. 1990

Answer: 2. 1980

Bt toxin is insect group-specific and is coded by a gene named cry. These genes were isolated from the bacterium, Bacillus thuringiensis for the first time in 1980.

Question 29. Bacillus thuringiensis is a bacterium found in

1. Water
2. Skin of cat
3. Soil
4. Surface of midgut

Answer: 3. Soil

The bacterium, Bacillus thuringiensis is a common soil bacterium.

Question 30. Bt cotton variety that was developed by the introduction of the toxin gene of bacillus thuringiensis (bt) is resistant to

1. Fungal diseases
2. Plant nematodes
3. Insect predators
4. Insect pests

Answer: 4. Insect pests

The bacterium, Bacillus thuringiensis is widely used in contemporary biology as an insecticide. It produces a protein toxin that kills certain insect pests.

NEET Biology Mcq Chapter Wise

Question 31. Some strains of Bacillus thuringiensis produce a protein that kills

1. Lepidopterans
2. Coleopterans
3. Dipterans
4. All of these

Answer: 4. All of these

Some strains of Bacillus thuringiensis produce a protein that kills insects like lepidopterans, coleopterans and dipterans. Thus, option (4) is correct.

Question 32. Match the following columns.

Answer: 1. A–1, B–2, C–3

Question 33. Bt toxin is

1. An intracellular crystalline protein
2. An extracellular crystalline protein
3. An intracellular monosaccharide
4. An extracellular polysaccharide

Answer: 1. An intracellular crystalline protein

Bt toxin is an intracellular crystalline protein. Specific Bt toxin genes obtained from Bacillus thuringiensis are used in producing several transgenic crop plants like cotton.

NEET Biology Mcq Chapter Wise

Question 34. Some of the characteristics of bt cotton are

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

Answer: 4. High yield and resistance to bollworms

The characteristic of Bt cotton is high yield and resistance to bollworms. Bt toxin genes were isolated from Bacillus thuringiensis and incorporated into cotton plants to form a genetically modified crop called Bt cotton. It provides resistance against the bollworm in cotton

Question 35. Bt toxin is lethal to insects as it

1. Inhibits protein synthesis
2. Generates excessive heat
3. Creates pores in the midgut epithelial cells, leading to cell swelling and lysis
4. Obstructs a biosynthetic pathway

Answer: 3. Creates pores in the midgut epithelial cells, leading to cell swelling and lysis

• Bt toxins are initially inactive protoxins but after ingestion by the insects, their inactive toxins become active due to the alkaline pH of the gut which solubilises the crystals.
• The activated toxin binds to the surface of the midgut epithelial cells, thus creating pores which cause cell swelling and lysis, further leading to the death of the insects.

NEET Biology Mcq Chapter Wise

Question 36. What triggers the activation of protoxin to active bt toxin of bacillus thuringiensis in bollworms?

1. Body temperature
2. The moist surface of the midgut
3. An alkaline ph of gut
4. An acidic ph of the stomach

Answer: 3. Alkaline ph of gut

• Bt toxins are initially inactive protoxins but after ingestion by the insects, their inactive toxins become active due to the alkaline pH of the gut which solubilises the crystals.
• The activated toxin binds to the surface of the midgut epithelial cells, thus creating pores which cause cell swelling and lysis, further leading to the death of the insects.

Question 37. Why is bt toxin not toxic to human beings?

1. The toxin recognises only insect-specific targets
2. Bt toxin activation requires temperature above the human body temperature
3. Bt toxin formation from pro bt state which requires a ph lower than one present in the human stomach
4. Conversion of pro bt to bt state takes place only in highly alkaline condition

Answer: 4. Conversion of pro bt to bt state takes place only in highly alkaline condition

Bt toxin is not toxic to human beings because the conversion of pro-Bt to Bt state takes place only in highly alkaline conditions.

Question 38. Cry I endotoxins obtained from Bacillus thuringiensis are effective against

1. Flies
2. Mosquitoes
3. Worms
4. Nematodes

Answer: 3. Worms

Bt toxin is insect group-specific and is coded by a gene named cry. These genes were isolated from Bacillus thuringiensis and are incorporated into several crop plants. The proteins encoded by the genes cry 1 Ac and cry 2 Ab control the cotton bollworms.

NEET Biology Mcq

Question 39. The protein products of genes cry I ac and cry ii ab are responsible for controlling

1. Bollworm
2. Roundworm
3. Moth
4. Fruitfly

Answer: 1. Bollworm

• The cry gene of Bacillus thuringiensis produces a protein, which forms crystalline inclusions in the bacterial spores.
• These crystal proteins are responsible for the insecticidal activities of bacterial strains. The protein encoded by the genes cry IAc and cry IIAb control the cotton bollworm and cry I Ab controls corn borer.

Question 40. Find out the odd one.

1. Cry 2 ab–cotton bollworm
2. Cry 1 ac–Colorado potato beetle
3. Cry 1 ab–corn borer
4. Cry 3 bb–corn rootworm

Answer: 2. Cry 1 ac–Colorado potato beetle

(2) Option (2) is odd because cry 1 Ac controls cotton bollworms whereas the Colorado potato beetle is controlled by cry 3 Ab.

Question 41. Corn has been made resistant to corn borer disease by the introduction of the gene

Cry 1 ac

Cry 2 ab

Cry 1 ab

Cry 2 ac

Answer: 3. Cry 1 ab

Corn has been made resistant to corn borer disease by the introduction of the gene cry IAb. This plant is known as Bt corn.

Question 42. A protein toxin produced by Bacillus thuringiensis is

1. Thurioside
2. Thurin
3. Subtilisin
4. None of these

Answer: 1. Thurioside

Thurioside (a toxin protein) is toxic to several insects and produced by the bacterium, Bacillus thuringiensis

NEET Biology Mcq

Question 43. Given below are certain characteristics of trioxide protein. Identify the correct characteristics.

1. It is activated by the alkaline ph of the gut of the insect pest.
2. It binds with the epithelial cells of the midgut of the insect pest ultimately killing it.
3. It does not kill the carrier bacterium which is itself resistant to this toxin.

Which of the statement given above are correct?

1. 1 And 2
2. 1 And 3
3. 2 And 3
4. 1, 2 And 3

Answer: 3. 2 And 3

All given statements are correct for trioxide protein. Thus, option (4) is correct.

Question 44. But tobacco was first cultured to kill

1. Hornworm
2. Bollworm
3. Stem borer
4. Tobacco budworm

Answer: 1. Hornworm

But tobacco was first cultured to kill hornworms. Tobacco plants containing a gene from a bacterium, Bacillus thuringiensis have been produced. This bacterial gene specifies an insecticidal protein that destroys the stomach lining of insects and kills them.

Question 45. Match the following columns.

Answer: 1. A–3, B–4, C–2, D–1

NEET Biology Mcq

Question 46. Consider the following statements.

1. The Bt toxin gene has been cloned from the bacteria.
2. Genetic engineering works only on animals and has not yet been successfully used on plants.
3. Strains of Bacillus thuringiensis are used in producing bioinsecticidal plants.

Which of the statements given above is correct?

1. 1 And 2
2. 1 And 3
3. 2 And 3
4. 1, 2 And 3

Answer: 2. 1 And 3

Statements 1 and 3 are correct whereas statement 2 is incorrect and can be corrected as Genetic engineering is done on both animals and plants for commercial use.

Question 47. Assertion a crop expressing a cry gene is usually resistant to a group of insects. Reason (r) cry proteins produced from bacillus thuringiensis are toxic to larvae of certain insects.

1. Both a and r are true and r is the correct explanation of a
2. Both a and r are true, but r is not the correct explanation of a
3. A is true, but r is false
4. Both a and r are false

Answer: 2. Both a and r are true, but r is not the correct explanation of a

• Both A and R are true, but R is not the correct explanation of A. Bacillus thuringiensis (Bt), a soil bacterium produces a Cry protein (crystal protein). This protein is toxic to the larvae of certain insects.
• There are several kinds of Cry proteins. Each Cry protein is toxic to a different group of insects. The gene encoding Cry protein, i.e. cry gene has been isolated and transferred into several crops. A crop expressing a cry gene is usually resistant to groups of insects.

Question 48. The RNAi stands for

1. Rna interference
2. Rna interferon
3. Rna inactivation
4. Rna initiation

Answer: 1. Rna interference

RNAi stands for RNA interference. In this process, a complementary dsRNA binds to the mRNA and prevents it from translating thereby, silencing it.

NEET Biology Mcq

Question 49. Rna interference involves

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

Answer: 3. Silencing of specific mRNA due to complementary RNA

• RNA interference (RNAi) is a method of cellular defence in all eukaryotes. It is a system within living cells that help 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). The source of dsRNA is retrovirus (having RNA genome).

Question 50. In RNAi, the genes are silenced using

1. Ds rna
2. Ss dna
3. Ss rna
4. Ds dna

Answer: 1. Ds rna

• Double-stranded RNA (dsRNA) is an effective trigger of gene silencing in vertebrate, invertebrate and plant systems.
• RNA interference (RNAi) is a method of cellular defence in all eukaryotes. It is a system within living cells that help 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). The source of dsRNA is retrovirus (having RNA genome).

Question 51. Tumour-inducing (ti) plasmid transforms

1. Animals
2. Plants
3. Bacteria
4. Fungi

Answer: 2. Plants

Agrobacterium tumefaciens is a pathogenic bacterium that produces crown galls or tumours in plants on infection. It contains a large Ti plasmid (tumour-inducing plasmid) and it can transfer a part of its plasmid DNA to the host plant.

Question 52. Which of the following nematodes infects the roots of the tobacco plants and reduces the yield?

1. Wuchereria
2. Enterobius
3. Meloidogyne incognita
4. Manduca sexta

Answer: 3. Meloidogyne incognita

• Nematodes, Meloidogyne incognita infects the roots of tobacco plants and causes a great loss by causing a reduction in yield.
• This infestation was prevented by using a novel strategy, which was based on the process of RNA interference (RNAi). RNA is a powerful reverse genetic tool to study gene function.

Question 53. Match the following columns and select the correct option.

Answer: 4. A-4, B-1, C-2, D-3.

Question 54. ‘Silencing of mRNA molecule’ in order to control the production of a harmful protein has been used in the protection of plants from

1. Bettles
2. Armyworm
3. Budworm
4. Nematodes

Answer: 4. Nematodes

‘Silencing of mRNA molecule’ in order to control the production of a harmful protein has been used in the protection of plants from nematodes.

Question 55. The dna of tobacco plants resistant to a nematode produces

1. An antifeedant
2. Both sense and antisense RNA
3. A particular hormone
4. Toxic protein

Answer: 2. Both sense and antisense RNA

• A nematode, Meloidogyne incognita infects the roots of tobacco plants, which reduce the production of
  tobacco. It can be prevented by using the RNA interference process.
• In this process, by using the Agrobacterium vector, nematode-specific genes were introduced into the host plants, which produced both sense and antisense RNA in the host cells.

Question 56. Rna interference is used for which of the following purposes in the field of biotechnology?

1. To develop a plant tolerant to abiotic stresses
2. To develop a pest-resistant plant against infestation by nematode
3. To enhance the mineral usage by the plant
4. To reduce post-harvest losses

Answer: 2. To develop a pest-resistant plant against infestation by nematode

• RNA interference is used to develop a pest-resistant plant against infestation by the nematode. It takes place in all eukaryotic organisms as a method of cellular defence.
• This method involves the silencing of a specific mRNA due to a complementary dsRNA molecule that binds to and prevents translation of the mRNA (silencing).

Question 57. Fill up the blanks.

1. Agrobacterium vectors are used to introduce …a… Specific genes into the host plant.
2. Rnai occurs in all eukaryotic organisms as a method of …b…
3. The genes …c… And …d… Control cotton bollworms.
4. …e… Has been introduced in bt corn to prevent infection of corn borer.

A to E in the above statements can be

1. A–fungal, B–pest resistance, C–cry 1AB, D–cry 2ab, E–cry 1ac
2. A–nematode, B –protection against nematodes, C–cry 1ac, D–cry 2ab, E–cry 1ab
3. A–insects,  B–cellular defence, C–cry 2ab, D–cry 1ab, E–cry 2ac
4. A–virus, B–protection against viral infection, C–cry 1ac, D–cry 2ab, E–cry 2ac

Answer: 2. A–nematode, B –protection against nematodes, C–cry 1ac, D–cry 2ab, E–cry 1ab

Question 58. Assertion agrobacterium tumefaciens is popular in genetic engineering because this bacterium is associated with the roots of all cereal and pulse crops. Reason (R) a gene incorporated in the bacterial chromosomal genome gets automatically transferred to the crops with which the bacterium is associated.

1. Both a and r are true and r is the correct explanation of a
2. Both a and r are true, but r is not the correct explanation of a
3. A is true, but r is false
4. Both a and r are false

Answer: 4. Both a and r are false

• Both A and R are false. These can be corrected as Agrobacterium tumefaciens a pathogenic bacterium that produces crown galls or tumours in plants on infection.
• It contains a large Ti plasmid (tumour-inducing plasmid) and it can transfer a part of its plasmid DNA to the host plant. Therefore, the bacterium can be used in the transfer of genes in biotechnological techniques.

Question 59. Two microbes found to be very useful in genetic engineering are

1. Crown gall bacterium and Caenorhabditis elegans
2. Escherichia coli and agrobacterium tumefaciens
3. Vibrio cholera and a tailed bacteriophage
4. Diplococcus sp. And Pseudomonas sp.

Answer: 2. Escherichia coli and Agrobacterium tumefaciens

Two microbes found to be very useful in genetic engineering are Escherichia coli and Agrobacterium tumefaciens.

Question 60. Which of the following bt crops is being grown in India by the farmers?

1. Cotton
2. Brinjal
3. Soyabean
4. Maize

Answer: 1. Cotton

Bt cotton is being grown in India by the farmers. It is pest resistant plant which could decrease the pesticides used.

Question 61. Which one is a transgenic crop?

1. Brinjal
2. Potato
3. Grape
4. Pomato

Answer: 4. Pomato

The pomato is a transgenic plant that is produced by grafting together a tomato plant and a potato plant, both of which are members of the family–Solanaceae.

Question 62. Which agriculturally important bacterial gene is isolated from rhizobium?

1. R-gene
2. F-gene
3. Nifgene
4. T-dna

Answer: 3. Nifgene

Nifgene is an N2-fixing gene present in Rhizobium. It is transferred into plants to develop transgenic plants.

Question 63. Consider the following statements about transgenic tobacco plants.

1. Transgenic tobacco plants contain a gene from a bacterium, bacillus thuringiensis.
2. Bt gene is an insecticidal protein which damages the inner lining of the insects and kills it (insect).
3. The tobacco plants having the bt gene produce their own insecticide.

Which of the statements given above is correct?

1. 1 And 2
2. 1 And 3
3. 2 And 3
4. 1, 2 And 3

Answer: 4. 1, 2 And 3

• All given statements are correct. Transgenic tobacco plants containing a gene (cry) from a bacterium, Bacillus thuringiensis have been produced.
• This bacterial gene specifies an insecticidal protein that destroys the stomach lining of the insects and kills them. The tobacco plants with this gene produce their own insecticide. Thus, option (4) is correct.

Question 64. Match the following columns.

Answer: 1. A–2, B–3, C–4, D–1

Biology MCQ For NEET With Answers Microbes As Biofertilisers

Question 1. Agriculture involving the use of biofertilizers is called

1. Manuring
2. Composting
3. Inorganic farming
4. Organic farming

Answer: 4. Organic farming

Organic farming is a form of agriculture that relies on techniques such as crop rotation, the use of green manure, compost, biofertilizers, and biological pest control.

Question 2. Biofertilizers include

1. Nitrogen-fixing cyanobacteria only
2. Nitrogen-fixing bacteria only
3. Protistans only
4. Bacteria, cyanobacteria, and fungi

Answer: 4. Bacteria, cyanobacteria, and fungi

• ‘Bio’ means ‘life’. Therefore, by definition, biofertilizers are living organisms that enrich the nutrient quality of the soil.
• It refers to the use of microbes instead of chemicals to enhance the nutrition of the soil. As a result, it is also less harmful and does not cause pollution. Types of biofertilizers are bacteria, fungi, and cyanobacteria.

Read And Learn More: NEET Biology Multiple Choice Question And Answers

Question 3. Which one of the following statements is incorrect?

1. Green manures are added to the soil
2. Fertilizers cause soil and water pollution
3. Biofertilizers improve soil fertility
4. Berseem is an ideal biofertiliser

Answer: 4. Berseem is an ideal biofertiliser

The statement in the option is incorrect and can be corrected as berseem (Trifolium alexandrinum) is green manure. The rest statements are correct.

Question 4. Organic farming is the technique of raising crops through the use of

1. Manure
2. Resistant varieties
3. Biofertilizers
4. All of the above

Answer: 4. All of the above

Organic farming is a form of agriculture that relies on techniques such as crop rotation, the use of green manure, compost, fertilizers, and biological pest control.

Biology MCQ For NEET With Answers

Question 5. Composted manure is formed from

1. Farmyard manure and green manure
2. Farm refuse and household refuse
3. Rotted vegetables and animals refuse
4. Organic wastes from which biogas is extracted

Answer: 3. Rotted vegetables and animal refuse

• Manure is composed of animal feces or urine and may contain livestock bedding, additional water, and wasted feed.
• It is a valuable fertilizer that contains a broad range of nutrients such as nitrogen (n), phosphorus (p), and potassium (k) as well as micronutrients such as copper (cu), manganese (Mn), and zinc (Zn). So, composited manure is formed from rotted vegetable and animal refuse.

Question 6. Humus is Haryana

1. Partially decomposed organic matter of soil
2. Completely decomposed organic matter of soil
3. Partially decomposed inorganic matter
4. Completely decomposed organic matter of pond

Answer: 2. Completely decomposed organic matter of soil

Humus is dark, organic material that forms in soil when plant and animal matter decays. When plants drop leaves, twigs, and other material to the ground, it piles up. The thick brown or black substance that remains after most of the organic litter has decomposed is called humus.

7. Which of the following is/are the approach (s) for biological farming?

1. Familiarity with various lifeforms inhabiting the field.
2. Gain knowledge about the life cycles, patterns of feeding, and habitat of predators and pests.

Choose the correct option.

1. Statement 1 is correct, but 2 is incorrect
2. Statement 1 is incorrect, but 2 is correct
3. Both statements 1 and 2 are correct
4. Both statements 1 and 2 are incorrect

Answer: 3. Both statements 1 and 2 are correct

Both statements I and ii are correct. An important part of the biological farming approach is to become familiar with the various lifeforms that inhabit the field, predators as well as pests, and also their life cycles, patterns of feeding, and the habitats that they prefer. This will help to develop appropriate means of biocontrol.

Biology MCQ For NEET With Answers

Question 8. Organisms that can fix atmospheric nitrogen in the soil are found among

1. Mosses
2. Green algae
3. Soil fungi
4. Bacteria

Answer: 4. Bacteria

Rhizobium bacteria fix atmospheric nitrogen in the soil.

Question 9. An organism used as a biofertilizer while raising a legume crop is

1. Nostoc
2. Anabaena
3. Clostridium
4. Rhizobium

Answer: 4. Rhizobium

Rhizobium is used as a biofertilizer for raising any legume crop. It is a symbiotic bacterium that lives in the root nodules of legumes and fixes atmospheric nitrogen into organic compounds.

Question 10. For symbiotic nitrogen fixation, the biofertilizer rhizobium enters the leguminous partner through the

1. Root nodules
2. Stem tissues
3. Root hairs before nodule formation
4. Root hairs after nodule formation

Answer: 3. Root hairs before nodule formation

• The rhizobium bacteria help leguminous plants by converting atmospheric nitrogen to soluble form for the plant to make proteins and in return the plant provides the bacteria with sugars or food.
• To develop a symbiotic relationship with the legume crop, rhizobium enters into the root hair before the formation of root nodules.

Biology MCQ For NEET With Answers

Question 11. In a barren land, the soil has been eroded due to overgrazing and wind or the soil also has been leeched. To restore the fertility of the soil, we should add

1. Legumes to the soil
2. Inorganic nutrients
3. Air
4. Water

Answer: 1. Legumes to the soil

• Legumes should be added to the soil to restore the fertility. Legumes fix the atmospheric nitrogen, release high-quality organic matter in the soil, and facilitate soil nutrients’ circulation and water retention.
• Based on these multiple functions, legume crops have a high potential for conservation agriculture, being functional either as growing crops or as crop residue.

Question 12. What is required for nitrogen fixation by rhizobium?

1. Potassium
2. Phosphorus
3. Nitrate
4. Sodium

Answer: 2. Phosphorus

Phosphorus plays an important role in symbiotic association for nitrogen fixation in leguminous plants by Rhizobium.

Question 13. Which of the following is a free-living aerobic and non-photosynthetic nitrogen-fixing bacterium?

1. Rhizobium
2. Nostoc
3. Azospirillum
4. Azotobacter

Answer: 4. Azotobacter

Azotobacter species are free-living, aerobic, and nonphotosynthetic nitrogen-fixing bacteria. They normally fix molecular nitrogen from the atmosphere without symbiotic relations with plants, although some acetobacter species are associated with plants.

Question 14. The most important of the symbiotic nitrogen-fixing bacteria, which forms nodules on the roots of legume plants is

1. Aspergillus
2. Rhizobium
3. Penicillium
4. Streptococcus

Answer: 2. Rhizobium

Rhizobium is a soil bacterium that fixes nitrogen after being established inside the root nodules of legumes (family Fabaceae). Rhizobia require a plant host, they cannot independently fix nitrogen.

Biology MCQs with answers for NEET

Question 15. Which one of the following statements is correct?

1. Legumes are incapable of fixing nitrogen
2. Legumes fix nitrogen only through specialized bacteria living in their nodulated roots
3. Legumes fix nitrogen independent of the bacteria that live in their roots
4. Legumes fix nitrogen only through bacteria forming nodules on any part of the plant

Answer: 2. Legumes fix nitrogen only through specialized bacteria living in their nodulated roots

• The statement in the option is correct. The rhizobium bacteria help leguminous plants by converting atmospheric nitrogen to soluble form for the plant to make proteins and in return the plant provides the bacteria with sugars or food.
• To develop a symbiotic relationship with the legume crop, rhizobium enters into the root hair before the formation of root nodules.

Question 16. The rhizobium is able to fix atmospheric nitrogen. This ability is due to the

1. Presence of the enzyme pyruvate dehydrogenase
2. Presence of the enzyme nitrogenase
3. Presence of the enzyme nitrate reductase
4. Symbiotic association with fungi

Answer: 2. Presence of enzyme nitrogenase

Rhizobium contains the enzyme nitrogenase, a mo-fe protein that helps in the conversion of atmospheric free nitrogen into ammonia.

Question 17. Root and stem nodules fixing atmospheric nitrogen are found in

• Vigna sinensis
• Sesbania aculeata
• Melilotus parviflora
• Sesbania rostrata

Answer: 2. Sesbania rostrata

Sesbania rostrata is a small semi-aquatic leguminous tree. It forms a symbiotic relationship with gram-negative rhizobia which helps in the formation of nitrogen-fixing nodules on both stem and roots.

Question 18. Which nitrogen-fixing bacteria is found in the root association of maize?

1. Aulosira
2. Azotobacter
3. Azospirillum
4. Exorrhiza

Answer: 3. Azospirillum

Bacterium azospirillum lipoferum forms a loose association with the roots of maize. Azospirillum is free-living bacteria, which absorbs free nitrogen from the soil, and air and converts it into salts of nitrogen like amino acids and enriches the soil.

Biology MCQs with answers for NEET

Question 19. What happens when we inoculate rhizobium in the wheat field?

1. No increase in production (nitrogen content of soil remains same)
2. A lot of increase in production (nitrogen content of soil increases)
3. The fertility of soil decreases
4. Fertility of soil increases

Answer: 1. No increase in production (nitrogen content of soil remains same)

When we inoculate rhizobium in wheat fields, there is no increase in production, and the nitrogen content of soil remains the same because rhizobium is a symbiotic bacterium that lives in the root nodules of legumes and fixes atmospheric nitrogen into organic compounds.

Question 20. An example of symbiotic bacteria.

1. Erwinia amylovora
2. Rhizobium leguminosarum
3. Xanthomonas campestris
4. Agrobacterium tumefaciens

Answer: 2. Rhizobium leguminosarum

Rhizobium leguminoserum nitrogen-fixing bacteria living in a symbiotic relationship with legumes. Common crop and forage legumes are peas, beans, clover, and soybean.

Question 21. The symbiotic association of fungi with the roots of higher plants is called

1. Eubacteria
2. Actinomycetes
3. Mycorrhiza
4. Lichen

Answer: 3. Mycorrhiza

A mycorrhiza is a symbiotic association between a fungus and the roots of a vascular plant. They are an important component of soil life and soil chemistry.

Question 22. Mycorrhiza is helpful in

1. Synthesis of food
2. Getting nutrients from the soil
3. Providing resistance against different regulators
4. Increase the fertility of the soil

Answer: 2. Getting nutrients from the soil

Mycorrhiza is a mutually beneficial relationship between fungi and the roots of higher plants. It helps in the absorption of water, minerals from organic matter, and protection from soil-borne pathogenic fungi.

Question 23. Mycorrhiza is a symbiotic association of roots of higher plants with

1. Actinomycetes fungi mainly
2. Basidiomycetes fungi mainly
3. Bacteria
4. Cyanobacteria

Answer: 2. Basidiomycetes fungi mainly

Mycorrhiza is a symbiotic association of roots of higher plants with basidiomycetes fungi mainly. The fungi commonly known as mushrooms, toadstools, puffballs, and bracket fungi are the basidiomycetes.

Question 24. The most common fungal partner of mycorrhiza belongs to the genus

1. Azotobacter
2. Glomus
3. Azolla
4. Frankia

Answer: 2. Glomus

Glomus is a genus of arbuscular mycorrhizal (am) fungi and all its species form symbiotic relationships (mycorrhizas) with plant roots.

Question 25. A good example of organic fertilizer, which improves phosphorus uptake is

1. Vam fungi
2. Rhizobium
3. Azospirillum
4. All of these

Answer: 2. Rhizobium

In endophytic mycorrhiza, fungal hyphae present inside or between the cells of the cortex, act as biofertilizers. In many grasses and some other crops, the fungal hyphae penetrate the cortical cells, which swell to form vesicles or arbuscules. This is called vesicular-arbuscular mycorrhiza (vam). It has a significant role in phosphate nutrition in plants.

Question 26. Mycorrhiza does not help the host plant in

1. Enhancing its phosphorus uptake capacity
2. Increasing its tolerance to drought
3. Enhancing its resistance to root pathogens
4. Increasing its resistance to insects

Answer: 4. Increasing its resistance to insects

1. Mycorrhiza shows the following benefits
2. Resistance to root-borne pathogens.
3. Tolerance to salinity and drought.
4. The overall increase in plant growth and development.
5. It has no role in increasing insect resistance in plants.

Question 27. In ectomycorrhizae,

1. Hyphae enter the plant cells and produce balloon-like structures
2. Fungal mycelia form a mantle on the root surface
3. Root nodules are produced
4. None of the above

Answer: 1. Hyphae enter the plant cells and produce balloon-like structures

• Hyphae of endomycorrhizal fungi penetrate the cell wall and invaginate the cell membrane. They enter into the plant cells, producing structures that are either balloon-like (vesicles) or dichotomously-branching invaginations (arbuscules).
• The structure of the arbuscules greatly increases the contact surface area between the hypha and the cell cytoplasm to facilitate the transfer of nutrients between them.

Biology MCQs with answers for NEET

Question 28. An example of endomycorrhiza is

1. Nostoc
2. Glomus
3. Agaricus
4. Rhizobium

Answer: 2. Glomus

Glomus is a genus of arbuscular mycorrhizal fungi which forms endomycorrhiza, a symbiotic association with plant roots.

Question 29. Ectomycorrhizae absorb and store nitrogen, phosphorus, potassium, and calcium in

1. Host epidermis
2. Host cortex
3. Root hair
4. Fungal mantle

Answer: 4. Fungal mantle

In ectomycorrhizae, fungal hyphae cover the surface of the root and form a fungal mantle around it. The hyphae absorb important plant nutrients such as nitrogen, phosphorus, potassium, calcium, and water from the soil and stored them in the mantle.

Question 30. Ectomycorrhiza are commonly found on the roots of

1. Pinus
2. Eucalyptus
3. Quercus
4. All of these

Answer: 4. All of these

Ectomycorrhizae form in the roots of around 2% of plant species, usually woody plants, including species from
the birch, dipterocarp, myrtle, beech, willow, pinus, eucalyptus, Quercus, oak, and rose families, etc. Thus, option.

Question 31. Ectomycorrhizae can be traced in the roots of

1. Maize
2. Groundnut
3. Rice
4. Trees like pine and oak

Answer: trees like pine and oak

Ectomycorrhizae form in the roots of around 2% of plant species, usually woody plants, including species from
the birch, dipterocarp, myrtle, beech, willow, pinus, eucalyptus, Quercus, oak, and rose families, etc. Thus, the option is correct.

Question 32. Mycorrhiza promotes plant growth by

1. Absorbing inorganic ions from the soil
2. Helping the plant in utilizing atmospheric nitrogen
3. Protecting the plant from infection
4. Serving as a plant growth regulator

Answer: 1. Absorbing inorganic ions from soil

• Mycorrhiza promotes plant growth by absorbing inorganic ions from the soil.
• The fungal hyphae absorb phosphorus from the soil and pass it to the plant.

Biology MCQs with answers for NEET

Question 33. The benefits of mycorrhiza are

1. Resistance to root-borne pathogen
2. Tolerance to salinity and pathogen
3. The overall increase in plant growth and development

Choose the correct option.

1. 1, 2 And 3
2. 1 And 3
3. 2 And 3
4. Only 2

Answer: 1. 1, 2 And 3

1. Resistance to root-borne pathogens.
2. Tolerance to salinity and drought.
3. The overall increase in plant growth and development.
4. All the given benefits of mycorrhiza are correct.

Question 34. Mycorrhiza helps in the absorption of

1. Nitrogen and phosphorus
2. Potassium and calcium
3. Water
4. All of the above

Answer: 4. All of the above

• All given nutrients help in absorption. In ectomycorrhizae, fungal hyphae cover the surface of the root and form a fungal mantle around it.
• The hyphae absorb important plant nutrients such as nitrogen, phosphorus, potassium, calcium, and water from the soil and store them in the mantle.

Question 35. Which one of the following microbes forms a symbiotic association with plants and helps them in their nutrition?

1. Azotobacter
2. Aspergillus
3. Glomus
4. Trichoderma

Answer: 3. Glomus

• Glomus is endomycorrhiza that helps in the absorption of nutrition especially phosphorus from soil.
• Glomus is a genus of arbuscular mycorrhizal fungi which forms endomycorrhiza, a symbiotic association with plant roots.

Question 36. The angiosperms having mycorrhiza are

1. Orchids
2. Sarcodes
3. Monotropa
4. All of these

Answer: 4. All of these

Mycorrhiza is found to be associated with all three given plants, i.e. Orchids, sarcodes, and Monotropa.

Question 37. Some blue-green algae can be used as biofertilizers as they are Karnataka

1. Photosynthetic
2. Surrounded by mucilage
3. Growing everywhere
4. Capable of fixing nitrogen

Answer: 4. Capable of fixing nitrogen

NEET Biology Mcq

Question 38. The cyanobacteria fix atmospheric nitrogen in

1. Cystolith
2. Heterocyst
3. Sheath
4. Leaves

Answer: heterocyst

A heterocyst is a differentiated cyanobacterial cell that carries out nitrogen fixation. The heterocysts function as the sites for nitrogen fixation under aerobic conditions. They are formed in response to a lack of fixed nitrogen (nh4 or no3).

Question 39. Heterocysts produce nitrogenase enzymes in the presence of

1. Oxygen
2. Carbon
3. Hydrogen
4. Carbon dioxide

Answer: 1. Oxygen

• Heterocysts are the special, pale yellow-colored cells in the filament of algae.
• Each heterocyst is distinctly different from other blue-green cells in the filament and possesses one or two polar nodules.
• Nitrogen fixation is done by the heterocysts. These produce the nitrogenase enzyme in the presence of oxygen.

Question 40. Nitrogen fixation in cyanobacteria requires two enzymes named

1. Amylase-lipase
2. DNA polymerase-ligase
3. Nitrogenase-hydrogenase
4. Nuclease-diastase

Answer: 3. Nitrogenase-hydrogenase

Nitrogen fixation in cyanobacteria requires two enzymes named as

1. Nitrogenase catalyzes the reduction of n2. Ammonia is the end product of the reaction.
2. Hydrogenase certain strains of Rhizobium sp. Have been found to produce nodules that lose little or noh2 during periods when nitrogenase is operative.

These strains are more efficient in n2 fixation because they possess a mechanism whereby h2 evolved by nitrogenase is recycled. The first step in the recycling process is the uptake of h2 catalysed by the enzyme hydrogenase in bacteroids.

Question 41. Which of the following elements acts as an enzyme activator in nitrogen fixation?

1. Mg
2. Fe
3. Mo
4. N

Answer: 3. Mo

During nitrogen fixation, the enzyme nitrogenase is activated in an anaerobic atmosphere by an enzyme activator molybdenum (mo).

NEET Biology Mcq

Question 42. Bga is chiefly used as fertilizer in

1. Wheat
2. Paddy
3. Mustard
4. Gram

Answer: 2. Paddy

Bga (blue-green algae) is used as a biofertilizer in paddy crops which increases fertility by nitrogen fixation. Mostly anabaena, nostoc, aulosira are used as fertilizer.

Question 43. In rice fields, which of the following operates?

1. Anabaena
2. Ferrobacterium
3. Rhizobium
4. Clostridium

Answer: 1. Anabaena

Certain species of Anabaena have been used on rice paddy fields, proving to be an effective natural fertilizer.

Question 44. Anabaena azollae is an endophytic cyanobacteria found in

1. Cycas roots
2. Anthoceros thallus
3. Azolla
4. Pinus stem

Answer: 3. Azolla

Anabaena azollae is an endophytic cyanobacteria found in Azolla. Tiny aquatic water fern (Azolla) and a microscopic filamentous blue-green alga or cyanobacterium (Anabaena azollae) grow together at the surface of quiet streams and ponds throughout tropical and temperate regions of the world.

Question 45. Blue-green algae are mainly used as biofertilizers in the field of which crop?

1. Gram
2. Millet
3. Rice
4. Maize

Answer: 3. Rice

• Blue-green algae is used as biofertilizers, in the field of rice or paddy.
• Bga (blue-green algae) is used as a biofertilizer in paddy crops which increases fertility by nitrogen fixation. Mostly anabaena, nostoc, aulosira are used as biofertilizers.

46. Which of the following cyanobacteria can fix atmospheric nitrogen?

1. Volvox
2. Oscillatoria
3. Nostoc
4. Anabaena

Choose the correct option.

1. 1, 2 And 3
2. 1, 2 And 4
3. 2, 3 And 4
4. 3 And 4

Answer: 3. 2, 3 And 4

All given cyanobacteria can fix atmospheric nitrogen except volvox. Cyanobacteria fix atmospheric nitrogen and increase the organic matter of the soil through photosynthetic activity, Nostoc, anabaena, oscillators, etc. Thus, the option is correct.

NEET Biology Mcq

47. A free-living nitrogen-fixing cyanobacterium that can also form a symbiotic association with the water fern Azolla is

1. Tolypothrix
2. Chlorella
3. Nostoc
4. Anabaena

Answer: 4. Anabaena

Anabaena is a genus of filamentous cyanobacteria that exist as plankton. It is known for nitrogen-fixing abilities and forms symbiotic relationships with certain plants, such as the water fern Azolla.

Question 48. Who reported the presence of associative nitrogen-fixing bacteria with the roots of maize plants?

1. Hellriegel and beijerinck
2. Gc fogg
3. J doberiner
4. Nj borlaug

Answer: 1. Hellriegel and beijerinck

• Biological nitrogen fixation in maize plants was discovered by the German agronomist Hermann Hellriegel and Dutch microbiologist Martinus Beijerinck.
• Biological nitrogen fixation (BNF) occurs when atmospheric nitrogen is converted to ammonia by an enzyme called nitrogenase.

Question 49. Free-living bacteria that can fix n 2 from the soil is

1. Clostridium
2. Azotobacter
3. Beijerinckia
4. All of these

Answer: 4. All of these

Free-living nitrogen fixers include the cyanobacteria, anabaena, nostoc, and genera such as Azotobacter, beijerinckia, and Clostridium.

Question 50. Which of the following is a non-symbiotic, anaerobic, and non-photosynthetic n 2-fixing bacterium?

1. Nostoc
2. Clostridium
3. Chlorobium
4. Azotomonas

Answer: 2. Clostridium

Nitrogen-fixing bacteria, which are present in the soil convert free nitrogen into soluble compounds, which are absorbed from the soil by plants. Free-living non-photosynthetic anaerobic nitrogen-fixing bacteria is Clostridium.

Question 51. Azolla pinata has been found as an important fertilizer for paddy crops. This quality is due to the presence of

1. Bacteria
2. Cyanobacteria
3. Fungi
4. All of the above

Answer: 2. Cyanobacteria

Cyanobacteria, anabaena azollae is present in the leaves of azolla pinnata. Due to this, Azolla is used as a biofertilizer in paddy crops.

NEET Biology Mcq

Question 52. Which is the best fertilizer?

1. Synthetic fertilizer
2. Bacillus thuringiensis and lichens
3. Azolla and cyanobacteria
4. All of the above

Answer: 3. Azolla and cyanobacteria

An effective cyanobacterial biofertilizer is azolla-anabaena symbiosis, which is a very efficient biological nitrogen fixer. Azolla is mostly used in agriculture, particularly in rice fields. Farmers have observed over 50% higher yields by using Azolla as a biofertilizer.

Question 53. Which of the following is common to azo spirillum, anabaena, nostoc, and oscillatory?

1. They are n2-fixer microbes
2. They are prokaryotic organisms
3. Both (1) and (2)
4. They are eukaryotic organisms

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

• Azospirillum is a gram-negative free-living bacteria, which absorbs free nitrogen from soil and air and converts it into salts of nitrogen-like amino acids and enriches soil nutrients.
• Nostoc, anabaena, and oscillatory fix atmospheric nitrogen and increase the organic matter of the soil through their photosynthetic activity. So, they all are prokaryotic, nitrogen fixing organisms. Thus, the option is correct.

Question 54. Azospirillum, a nitrogen-fixing bacteria, has been found in the root association of maize, and anabaena is found in the roots of

1. Rice
2. Cycas
3. Sorghum
4. All of these

Answer: 2. Cycas

Azospirillum lipoferum, is a n2-fixing bacterium that is found in association with the roots of certain tropical grasses like cycas. It has been found to supply the plants with nitrogen.

NEET Biology Mcq Chapter Wise

Question 55. Which of the following statement is correct?

1. Cyanobacteria such as anabaena and Nostoc are important mobilizers of phosphates and potassium for plant nutrition in the soil
2. At present it is not possible to grow maize without chemical fertilizers
3. Runoff from agricultural areas rich in chemicals fertilizers may lead to the eutrophication of nearby water bodies
4. Both azotobacter and rhizobium fix atmospheric nitrogen in root nodules of plants

Answer: 3. Runoff from agricultural areas rich in chemicals fertilizers may lead to eutrophication of nearby water bodies

• Excess fertilizer in the environment, especially nitrogen and phosphorus can pollute local groundwater as well as lakes and streams resulting in eutrophication. Other statements are incorrect and can be corrected as
• Cyanobacteria anabaena and nostoc have heterocysts that help in nitrogen fixation. Hence, these are important mobilizers of nitrogen.
• Maize can be grown without chemical fertilizers, by using organic farming.
• Azotobacter is a free-living bacteria that fix nitrogen but do not occur in root nodules like rhizobium.

Question 56. Vam is

1. Vesicular arbuscular mycorrhizae
2. Variable adenine mutation
3. Variable associative mutualism
4. Vitamins and minerals

Answer: 1. Vesicular arbuscular mycorrhizae

Question 57. Vam helps in

1. Nitrate nutrition
2. Phosphate nutrition
3. Preventing infection
4. Denitrification

Answer: 2. Phosphate nutrition

Vesicular arbuscular mycorrhizae (vam) has a significant role in phosphate nutrition in plants.

Question 58. Vam is seen in

1. Pea
2. Oak
3. Peach
4. Grasses

Answer: 4. Grasses

Vam is vesicular-arbuscular mycorrhizae which are endomycorrhizal found in association with grasses and members of the family– Orchidaceae. Eucalyptus, oak, and pinus have only ectomycorrhizae.

NEET Biology Mcq Chapter Wise

Question 59. Using green manure increases crop yield by

1. 5-10%
2. 15-25%
3. 30-50%
4. 80-90%

Answer: 3. 30-50%

Quick-growing crops cultivated in soil plowed with green manure increase crop yield by 30-50%.

Question 60. The following are commonly used as green manure in India

1. Lentil
2. Sunnhemp
3. Cowpea
4. All of these

Answer: 4. All of these

Sunn hemp is a tropical plant of the legume family. It is used as a source of green manure, fodder, and lignified fiber. Cowpea is also a legume used as grain or vegetables. Lentil prevents soil erosion.

61. Manure supply following nutrients to plants

1. Nitrogen (n)
2. Phosphorus (p)
3. Potassium (k)
4. All of the above

Answer: 4. All of the above

Indian soils are usually very poor in organic matter and nitrogen content where constant leaching and removal of crops deprive the soil of mineral contents. Manure can help to supply vital nutrients like n, p, k to plants.

Question 62. Assertion (A) Leguminous plants are best preferred for crop rotation. Reason (R) They have root nodules, which have nitrogen-fixing bacteria clostridium.

1. Both a and r are true and r is the correct explanation of a
2. Both a and r are true, but r is not the correct explanation of a
3. A is true, but r is false
4. Both a and r are false

Answer: 3. A is true, but r is false

• A is true, but r is false because, in the rotation of crops, leguminous crops like pulses, beans, peas, and groundnut are used. The leguminous plants are grown alternately with non-leguminous plants to restore the fertility of the soil.
• These plants have the ability to fix atmospheric nitrogen to form nitrogen compounds through the help of certain bacteria (rhizobium) present in their root.

NEET Biology Mcq Chapter Wise

Question 63. Farmers have reported over 50% higher yields of rice by using the biofertilizer

1. Azolla pinnata
2. Cyanobacteria
3. Legume – rhizobium symbiosis
4. Mycorrhiza

Answer: 1. Azolla pinnata

Farmers have reported over 50% higher yields of rice by using the biofertilizer Azolla pinnata

Question 64. A straight fertilizer is one, which is

1. Absorbed by roots directly
2. Absorbed by the plants from aerial spray
3. Having only one primary nutrient
4. Not easily leached

Answer: 3. Having only one primary nutrient

A fertilizer, which contains only one primary nutrient is known as straight fertilizer or simple fertilizer.

Question 65. Which one of the following is not used in organic farming?

1. Snail
2. Glomus
3. Earthworm
4. Oscillatoria

Answer: 1. Snail

Organic farming is a method of a farming system that primarily aimed to keep the soil alive and in good health by use of organic wastes and other biological material along with beneficial microbes (biofertilizers) to release nutrients to crops for increased sustainable production in an ecofriendly, pollution free environment. Glomus (fungi), earthworms,s, and oscillators are used in organic farming. Snails are not used in it.

Question 66. Which of the following is used as fertilizer?

1. Cyanobacteria
2. Yeast
3. Symbiotic bacteria
4. Free-living bacteria

Choose the correct option.

1. 1, 2 And 3
2. 1, 3 And 4
3. 2, 3 And 4
4. 1, 2 And 4

Answer: 2. 1, 3 And 4

• All given organisms are used biofertilizers except yeast. Cyanobacteria or blue-green algae is the most suitable source of biofertilizer, particularly in rice fields,
• Example: nostoc, anabaena. Rhizobium is a symbiotic bacterium that lives in the root nodules of legumes and fixes atmospheric nitrogen into organic compounds.
• Azospirillum and acetobacter are free-living bacteria that absorb free nitrogen from soil, and air and convert it into salts of nitrogen like amino acids and enrich soil nutrients.

NEET Biology Mcq Chapter Wise

Question 67. Match the items in column I with those in column ii and choose the correct answer.

Answer: 1. A–3, b–1, c–5, d–2

Question 68. Which one of the following pairs is correctly matched?

1. Rhizobium – a parasite in the roots of leguminous plants
2. Mycorrhizae – mineral uptake from the soil
3. Yeast – production of biogas
4. Myxomycetes – the disease ringworm

Answer: 2. Mycorrhizae – mineral uptake from the soil

Matched pair. Other options are incorrectly matched pairs and can be corrected as rhizobium is a genus of bacteria associated with the formation of root nodules on plants. Myxomycetes, also called metazoa is a phylum of fungus-like organisms within the kingdom–Protista, commonly known

Question 69. Which one of the following is not a nitrogen-fixing organism?

1. Anabaena
2. Pseudomonas
3. Azotobacter
4. Nostoc

Answer: 2. Pseudomonas

Pseudomonas perform denitrification or the reduction of nitrates into nitrogen gas. It is not a nitrogen–fixing organism. Anabaena, nostoc, and azotobacter help in nitrogen fixation.

Question 70. Which one of the following is a non-symbiotic biofertilizer?

1. Azotobacter
2. Anabaena
3. Rhizobium
4. Vam

Answer: 1. Azotobacter

Azotobacter is a free-living nitrogen-fixing bacterium, so it is a non-symbiotic biofertilizer. Rhizobium is symbiotic and found in the root nodules of leguminous plants. Anabaena occurs in association with Azolla. Vam is vesicular arbuscular mycorrhizae.

Question 71. Which of the following belongs to free-living nitrogen-fixing bacteria?

1. Rhizobium
2. Azospirillum
3. Azotobacter

Choose the correct option.

1. 1 And 2
2. 1 And 3
3. 2 And 3
4. 1, 2 And 3

Answer: 3. 2 And 3

All given species belong to nitrogen-fixing bacteria except rhizobium. Azospirillum and acetobacter are free-living nitrogen-fixing bacteria. Free-living n2-fixing bacteria fix atmospheric nitrogen in the soil and make it available for the higher plant. Thus, the option is correct.

72. A natural source of nitrogenous fertilizer is

1. Tobacco leaves
2. Urea
3. Guano
4. Bonemeal

Answer: 3. Guano

Guano is a natural nitrogenous fertilizer obtained from bird droppings.

Question 73. Match the following columns and choose the correct option from the codes given below.

Answer: 4. A–2, b–4, c–5, d–3

Biology MCQs with answers for NEET Microbes in Human Welfare Miscellaneous

Question 1. The branch of biology which deals with the study of microbes is called

1. Palynology
2. Zoology
3. Microbiology
4. Botany

Answer: 3. Microbiology

Microbiology is the study of microbes or microorganisms, those being unicellular, multicellular or acellular. It encompasses numerous sub-disciplines including virology, parasitology, mycology and bacteriology.

Question 2. Which of the following microorganism is present in hot springs?

1. Thermoplasma
2. Halobacterium
3. B. Brevis
4. A. Niger

Answer: 1. Thermoplasma

Thermophilic microorganisms found in hot springs, e.g. Bacterium, thermoplastic.

Read And Learn More: NEET Biology Multiple Choice Question And Answers

Question 3. The energy obtained from biological resources is called

1. Electrical energy Rajasthan
2. Mechanical energy
3. Bioenergy
4. Life energy

Answer: 3. Bioenergy

Energy obtained from biological sources is called bioenergy, which is of two types, i.e. Animal energy and biofuels.

Biology MCQs with answers for NEET

Question 4. The botanical name of berseem (Egyptian clover) is

1. Lens esculent
2. Crotalaria juncea
3. Cyamopsis tetragonoloba
4. Trifolium alexandrinum

Answer: 4. Trifolium alexandrinum

The botanical name of berseem is Trifolium alexandrinum which is an annual clover, cultivated mostly in irrigated sub-tropical regions and used as fodder, mainly for cattle and milk buffalo.

Question 5. Fill up the blanks.

1. Bread making – A
2. Commercial production of citric acid – B
3. The traditional drink of South India – C
4. Gives the characteristic feature of Swiss-cheesed

Choose the correct option

1. A–penicillium roqueforti, B–penicillium, C– toddy, d–aspergillus niger
2. A–lactobacillus, B–aspergillus niger, C–Toddy, D–acetobacter acetic
3. A–Saccharomyces cerevisiae, B–aspergillus niger, C–Toddy, D–propionibacterium shermanii
4. A–propionibacterium shermanii, B– bacillus, C–toddy, D–lactobacillus

Answer: 3. A–Saccharomyces cerevisiae, B–aspergillus niger, C–Toddy, D–propionibacterium shermanii

Question 6. …… Are not nitrogen-fixing bacteria.

1. Nostoc, clostridium and azotobacter
2. Anabaena, azotobacter and rhizobium
3. Nitrosomonas, nitrosococcus and nitrobacter
4. Aulosira and bacillus polymyxis

Answer: 3. Nitrosomonas, nitroso-coccus and Nitrobacter

The conversion of ammonia to nitrite and nitrite to nitrate is carried out by certain bacteria in the soil. The chemosynthetic bacteria nitrosomonas, nitrobacter and nitrosococcus carry out denitrification. So, they are not nitrogen-fixing bacteria.

Biology MCQs with answers for NEET

Question 7. Match the following columns.

Answer: 2. A–1, b–3, c–4, d–2

Question 8. Match the following columns.

Answer: 3. A–2, b–1, c–4, d–3

Question 9. Which of the following is wrongly matched in the given table?

Answer: 4. Wrongly matched

Pair and can be corrected as clostridium bretylium is used for the production of butyric acid. Candida lipolytic is the source of lipase. Rest options are correctly matched pairs.

Biology MCQs with answers for NEET

Question 10. Edible fungus is

1. Agaricus bisporus
2. Volvariella volvacea
3. Pleurotus Florida
4. All of the above

Answer: 4. All of the above

All given species are edible fungi. Edible fungus is a nutritious food that can be consumed by human beings and other living organisms and does not cause any side effects. Thus, option

Question 11. The calorific value of biogas is

1. 10-20 MJ/kg
2. 23-28 MJ/kg
3. 30-40 MJ/kg
4. 5-10 MJ/kg

Answer: 3. 30-40 MJ/kg

• Biogas is composed of gases such as CO2 (around 30%), ch4 (around 70%) and trace amounts of n2, o2 and water vapour.
• Its combustible portion is ch 4. Raw biogas has an average calorific value of about 30-35 MJ/kg. After purification, biogas can have a calorific value of 40-45mj/kg

Question 12. Assertion agriculture output increased several times after the introduction of DDT. Reason (R) DDT was the first insecticide used on a wide scale.

1. Both a and r are true and r is the correct explanation of a
2. Both a and r are true, but r is not the correct explanation of a
3. A is true, but r is false
4. Both a and r are false

Answer: 1. Both a and r are true and r is the correct explanation of a

Biology MCQs with answers for NEET

Question 13. In September 2001, which of the following was used as a bioweapon agent in America?

1. Botulinum
2. Anthrax (Bacillus anthracis)
3. Poliovirus
4. Aids virus

Answer: 2. Anthrax (Bacillus anthracis)

Question 14. Select the mismatch.

1. Frankia – Alnus
2. Rhodospirillum – mycorrhiza
3. Anabaena – nitrogen-fixer
4. Rhizobium – alfalfa

Answer: 2. Rhodospirillum – mycorrhiza

Mismatched and can be corrected as rhodospirillum is an anaerobic, free-living bacterium that helps in nitrogen fixation. Whereas mycorrhiza is the symbiotic relationship between fungi and the roots of higher plants. The rest of the options are correctly matched pairs.

Question 15. Which of the following herbicides and defoliants were used by our military in its herbicidal warfare programme during the Vietnam War?

1. Agent black
2. Agent Orange
3. Super orange
4. Both (2) and (3)

Answer: 4. Both (2) and (3)

Agent Orange and Super Orange were used from 1961 to 1971. They released toxins, which caused harm to the health of those exposed during the Vietnam War. Agent blue and white were part of the same programme but did not contain toxins.

Question 16. Match the following columns and choose the correct option from the codes given below.

Answer: 1. A–4, b–3, c–1, d–2

Question 17. Match the following columns.

Answer: 1. A–4, b–3, c–2, d–1

Biology MCQ For NEET With Answers Microbes As Biocontrol Agents

Question 1. The natural method of pest and pathogen control involving the use of viruses, bacteria, and other insects is called

1. Biochemical control
2. Biological gene control
3. Biocontrol
4. Chemical control

Answer: 3. Biocontrol

The natural method of pest and pathogen control involving the use of viruses, bacteria, and other insects is called biocontrol or biological control. For example, ladybird beetle feeds on aphids, while dragonflies prey upon mosquitoes.

Question 2. The biological control component is central to advanced agricultural production. Which of the following is used as a third-generation pesticide?

1. Pathogens
2. Pheromones
3. Insect repellents
4. Insect hormone analogs

Answer: 4. Insect hormone analogs

Professor Carroll M. Williams (1956) was probably the first to recognize the potential of applying insect hormones in pest control and in 1967 hailed them as ‘third-generation pesticides. The first generation is exemplified by an arsenate of lead and the second by ddt.

Read And Learn More: NEET Biology Multiple Choice Question And Answers

Question 3. Ipm (integrated pest management) involves

1. Biological control
2. Pesticides
3. Confusion technique
4. Biofertilizers

Answer: 1. Biological control

According to IBM, biological control methods should be followed and the use of chemical pesticides should be minimized.

Biology MCQ For NEET With Answers

Question 4. Integrated pest management (IPM) discourages the excessive use of

1. Biological methods
2. Chemical pesticides
3. Mechanical methods
4. Variable cultural controls

Answer: 2. Chemical pesticides

• Ipm discourages the excessive use of chemical pesticides. Sustainable pest management (spam) is otherwise known as integrated pest management (pm).
• Ipm involves the use of different pest control methods, which are ecologically safe, for example, biological control methods, and better agricultural practices like crop rotation, sanitation, etc.

Question 5. A biocontrol agent to be a part of integrated pest management (ipm) should be

1. Species-specific and symbiotic
2. Free-living and broad spectrum
3. Narrow spectrum and symbiotic
4. Species-specific and inactive on

Answer: 4. Species-specific and inactive on

A biocontrol agent to be a part of an item should be species-specific and inactive on non-target organisms.

Question 6. The latest trend in plant disease control in Punjab

1. Chemical control
2. Biological control
3. Good manure and fertilizer
4. Breeding for disease resistance

Answer: 2. Biological control

Biological pest control is one of the suitable methods, i.e. Use of other organisms to kill the pests. Thus, the latest trend in plant disease control is biological control.

Question 7. Milkweed vine is being eradicated from citrus with the help of herbicide

1. Phytophthora parthenium
2. Phytophthora palmivora
3. Pyrethrin
4. 2, 4- D

Answer: 2. Phytophthora palmivora

The first bioherbicide developed in 1961 was a mycoherbicide derived from a fungus, phytophthora palmivora which controls the growth of milkweed vines in citrus orchards.

Biology MCQ For NEET With Answers

Question 8. The free-living fungus Trichoderma can be used

1. For killing insects
2. As a biological control of plant diseases
3. To control butterfly caterpillars
4. For producing antibiotics

Answer: 2. As a biological control of plant diseases

Trichoderma is a free-living saprophytic fungus that most commonly lives on dead organic matter in the soil and rhizosphere. It acts as a biopesticide for the biological control of many soil-borne plant diseases.

Read And Learn More: NEET Biology Multiple Choice Question And Answers

Question 9. Consider the following statements.

1. Ladybirds and dragonflies are used to get rid of aphids and mosquitoes.
2. The bacteria Bacillus thuringiensis (Bt) are used to control butterflies.
3. Trichoderma sp. Is present in root ecosystems where they act against several plant pathogens.
4. Rhizobium is a symbiotic bacterium that lives in the stem of legumes.

Which of the statements given above is correct?

1. 1, 2 And 3
2. 1, 3 And 4
3. 2, 3 And 4
4. 2 And 4

Answer: 1. 1, 2 And 3

• All given statements are correct except statement iv. The incorrect statement can be corrected as
• Rhizobium is a symbiotic bacterium that lives in the root nodules of legumes and fixes atmospheric nitrogen into organic compounds.

Question 10. Match the following columns

Answer: 2. A–3, b–4, c–2, d–1

Question 11. Microbe used for biocontrol of pest butterfly caterpillars is

1. Saccharomyces cerevisiae
2. Bacillus thuringiensis
3. Streptococcus sp.
4. Trichoderma sp.

Answer: 2. Bacillus thuringiensis

• Biopesticides are biological agents that are used to control weeds, insects, and pathogens. The microorganisms used as biopesticides are viruses, bacteria, protozoan, fungi, and mites.
• The spores of Bacillus thuringiensis bacterium produce an insecticidal cry protein that kills the larvae of insects upon ingesting them. Thus, bacillus thuringiensis is a biopesticide for butterfly caterpillars

Biology MCQ For NEET With Answers

Question 12. Trichoderma harzianum has proved a useful microorganism for

1. Bioremediation of contaminated soils
2. Reclamation of wastelands
3. Gene transfer in higher plants
4. Biological control of soil-borne plant pathogens

Answer: 4. Biological control of soil-borne plant pathogens

• Trichoderma harzianum is a useful microorganism for the biological control of soil-borne plant pathogens.
• It is a fungus that is also used as a fungicide. It is used for foliar application, seed treatment, and soil treatment for suppression of various diseases causing fungal pathogens.

Question 13. The viruses which have been tested as insecticides against the serious pest of cotton Heliothis species are

1. Cytoplasmic polyhedrosis virus
2. Entomopoxvirus
3. Nuclear polyhedrosis
4. All of the above

Answer: 4. All of the above

• Heliothis is a genus of moths, whose larvae are agricultural pests on crop species such as tobacco, cotton, soybean, and pigeon pea.
• The viruses, which have been tested as insecticides against the serious pest of cotton Heliothis species are cytoplasmic polyhedrosis virus and entomopoxvirus, and nuclear
  polyhedrosis.

Question 14. Ecological suicide is forced on to rice moth Corcyra cephalonica by a compound extracted from

1. Chrysanthemum
2. Neem
3. Eichhornia crassipes
4. All of the above

Answer: 3. Eichhornia crassipes

• Ecological suicide is forced on to rice moth, Corcyra cephalonica by a compound extracted from Eichhornia crassipes. The prothoracic gland of insects secretes molting hormones or ecdysone which is responsible for the molting, pupation, and maturation of insects.
• This hormone can be used to bring the insect into developing conditions during unfavorable seasons, thus forcing them to commit ecological suicide. One such compound is isolated from Eichhornia crassipes, which has a similar mode of action.

Biology MCQ For NEET With Answers

Question 15. Which of the following can be used as a biocontrol agent in the treatment of plant disease?

1. Trichoderma
2. Chlorella
3. Anabaena
4. Lactobacillus

Answer: 1. Trichoderma

Fungus Trichoderma is a biological control agent that is being used in the treatment of plant diseases.

Question 16. Which of the following statements regarding baculoviruses as biocontrol agents is/are correct?

1. Baculoviruses are pathogens that attack insects and other arthropods.
2. Most of these biocontrol agents belong to the genus– nucleopolyhedrovirus.
3. They do not harm plants mammals, birds, fish, and other non-target insects.
4. Baculoviruses are helpful in integrated pest management (ipm) programs, in which beneficial insects are conserved.

Choose the correct option.

1. 1, 2 And 3
2. 1, 2 And 4
3. 2, 3 And 4
4. 1, 2, 3 And 4

Answer: 4. 1, 2, 3 And 4

• All given statements are correct. Baculovirus Heliothis (a group of viruses) are known to infect the larval stages of many harmful insects beetles, wasps, and ants.
• A number of baculoviruses, which are used as biopesticides belong to the genus nucleopolyhedrovirus. These biological weapons are effective as potential biological control of harmful insects and are harmless to non-target organisms (plants, birds, mammals, non-target insects, etc).
• Baculoviruses are helpful in integrated pest management (ipm) programs in which beneficial insects are conserved.

Question 17. One of the following is third-generation pesticides

1. Chemosterilants
2. Organochlorines
3. Antifeedants
4. Carbamates

Answer: 3. Antifeedants

Antifeedants are organic compounds produced by plants to inhibit attack by insects and grazing animals. So, they are third-generation pesticides.

Biology MCQs with answers for NEET

Question 18. The antifeedant compound is extracted from

1. Sesbania rostrata
2. Trifolium repens
3. Azadirachta indica
4. None of the above

Answer: 3. Azadirachta indica

Azadirachtin from indian neem tree azadirachta indica, is a most versatile antifeedant

Question 19. Thuriocide is released by

1. Bacillus thuringiensis
2. Virus
3. Fungi
4. Protozoan

Answer: 1. Bacillus thuringiensis

Thuriocide is a toxin produced by the bacterium, bacillus thuringiensis. Thus, it is of bactericidal origin. It is first used as a bioinsecticide on a commercial scale in the world, as it is highly effective against disease-causing insects like flies, moths, mosquitoes, etc. If consumed by mistake, it acts as a stomach poison.

Question 20. The cultivation of cotton has been much in the news. The prefix bt refers to

1. ‘Barium-treated’ cotton seeds
2. ‘Bigger thread’ variety of cotton with better tensile strength
3. ‘Biotechnology’ process using restriction enzymes and ligases
4. An endotoxin gene carried by bacillus thuringiensis

Answer: 4. An endotoxin gene carried by Bacillus thuringiensis

In Bt cotton, bt means carrying an endotoxin gene from Bacillus thuringiensis. Specific Bt toxin genes were isolated from Bacillus thuringiensis and incorporated into several crop plants such as cotton, and corn. The toxin is coded by a gene named cry.

21. Which bacterium was first used as biopesticide on a commercial scale in the world?

1. Bacillus thuringiensis
2. Escherichia coli
3. Pseudomonas aeruginosa
4. Agrobacterium tumefaciens

Answer: 1. Bacillus thuringiensis

Thuriocide is a toxin produced by the bacterium, bacillus thuringiensis. Thus, it is of bactericidal origin. It is first used as a bioinsecticide on a commercial scale in the world, as it is highly effective against disease-causing insects like flies, moths, mosquitoes, etc. If consumed by mistake, it acts as a stomach poison.

Question 22. Cry I endotoxins obtained from Bacillus thuringiensis are effective against

1. Mosquitoes
2. Flies
3. Nematodes
4. Bollworms

Answer: 4. Bollworms

Cry I endotoxin obtained from Bacillus thuringiensis is effective against bollworms. A bollworm is a common term for any larva of a moth that attacks the fruiting bodies of certain crops, especially cotton.

Biology MCQs with answers for NEET

Question 23. Bioherbicides and bioinsecticides

1. Are non-persistent, non-toxic, and biodegradable
2. Maintain the biodiversity and stability of the ecosystem
3. Decrease the chances of environmental pollution and degradation
4. All of the above

Answer: 4. All of the above

Bioherbicides and bioinsecticides are biocontrol agents that exhibit high pest specificity and biodegradability. Thus, they are non-persistent in the environment and do not cause environmental pollution. Due to their host specificity, they maintain biodiversity and ecological stability.

Question 24. The first bioherbicide developed in 1981 was based on

1. Phytophthora palmivora
2. Phytophthora infestans
3. Bacillus thuringiensis
4. Azadirachta indica

Answer: 1. Phytophthora palmivora

The first bioherbicide was developed in 1981. It is a mycoherbicide, based on the fungus, phytophthora palmivora, which controls the growth of milkweed vines in citrus orchards.

Question 25. Devine and College are two trade names in agriculture. They are used as

1. Bioinsecticides
2. Natural insecticides
3. Biofungicides
4. Bioherbicides

Answer: 4. Bioherbicides

• Devine is the first bioherbicide registered in the united states and is used for controlling milkweed vines. College is another bioherbicide made from Colletotrichum gloeosporioides.
• the anthracnose-causing fungal pathogen and is used to control aeschynomene Virginia in rice and soybean crops. So, they are used as bioherbicides.

Question 26. Most recent insecticides in India are

1. Chlorinated hydrocarbons
2. Organophosphorus compounds
3. Carbamates
4. Pyrethroids

Answer: 4. Pyrethroids

Pyrethroids are the most recent insecticides in India. These are called ‘third generation insecticides’, for example, deltamethrin. Chlorinated hydrocarbons are first-generation insecticides. Carbamate and organophosphorus are second-generation insecticides.

Question 27. Pyrethrin is obtained from

1. Azadirachta indica
2. Rosa indica
3. Poa indica
4. Chrysanthemum

Answer: 4. Chrysanthemum

Pyrethrins are a class of organic compounds normally derived from chrysanthemum cinerariifolium. They have potent insecticidal activity by targeting the nervous systems of insects. Pyrethrins are less toxic pesticides from a human health standpoint.

Biology MCQs with answers for NEET

Question 28. Which among the following is a mycoherbicide?

1. Beauveria bassiana
2. Bacillus thuringiensis
3. Xanthomonas sp.
4. Alternaria crassa

Answer: 4. Alternaria crassa

A mycoherbicide is a herbicide based on a fungus, Alternaria crassa. As a biological agent, these ‘mycoherbicides act by producing toxic compounds that dissolve the cell walls of targeted plants.

29. Which weed has been eradicated by biological control?

1. Parthenium
2. Cactus
3. Eichhornia
4. Chrysanthemum

Answer: 2. Cactus

Cactus has been eradicated by the method of biological control. It was done by introducing the cochineal insect, cactoblastis cactorum. The insect is a type of moth that exceptionally feeds on the cactus plant.

30. Biological control of weeds is carried out by

1. Insects that feed on weeds and not the crop
2. Use of pathogen microbes that cause disease only in weeds
3. Both (1) and (2)
4. Use of chemical pesticides

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

Biological weed control involves the use of living organisms such as insects, nematodes, bacteria, or fungi to reduce weed populations. These organisms feed upon or cause diseases in weeds only and do not affect other crops.

Question 31. Confusion technique involves

1. Laying traps containing pheromones
2. Confusing insects by releasing sterile males
3. Spreading pheromone containing hydrophobic papers
4. Introducing pheromones at juvenile

Answer: 3. Spreading pheromone containing hydrophobic papers

• ‘Confusion technique’ involves the use of pheromones or sex attractants. In this technique, hydrophobic paper having pheromones is placed over the crop area, due to which characteristic smell is spread over.
• The whole field and thus males are unable to locate the females. This technique helps to prevent the mating of pests and thus check their population.

Question 32. Fruitflies have been controlled by

1. Sterilization
2. Pheromonal compounds as synthetic methyl eugenol
3. Cultural control
4. All of the above

Answer: 2. Pheromonal compounds as synthetic methyl eugenol

• A large number of pheromones have been identified and their usefulness as bait or an attractant to collect a large number of insects to be killed or herded away from the opposite sex has been proved.
• Some of these compounds are phenols, which attract the grass grubs and others like synthetic methyl eugenol have practically been used for controlling fruit flies.

Question 33. Which bioherbicide was first used?

1. Mycoherbicide
2. Molluscoherbicide
3. Nematoherbicide
4. Insecticide

Answer: 1. Mycoherbicide

The first bioherbicide was developed in 1981. It is a mycoherbicide, based on the fungus, phytophthora palmivora, which controls the growth of milkweed vines in citrus orchards.

NEET Biology Mcq

Question 34. Agrobacterium radiobacter strain 

1. Fungal pesticide
2. Microbial pesticide
3. Mycoherbicide
4. Viral pesticide

Answer: 2. Microbial pesticide

Agrobacterium radiobacter strain k1026 is a microbial pesticide that can be used to treat germinating seeds or roots and stems of certain stone fruit (such as cherries and plums), nut trees, and ornamentals to protect them from crown gall disease.

Question 35. Which of the following statements is/are correct?

1. Herbicides kill plants mostly by blocking photosystem-ii and occasionally phloem transport
2. Insecticides kill insects mostly through impairment of nerve conduction and sometimes through respiratory arrest
3. Both (1) and (2)
4. None of the above

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

• Herbicides kill weeds and unwanted plants in cultivated land. They kill plants mostly by blocking photosystem-ii and occasionally phloem transport.
• Insecticides are those chemicals that destroy or kill insects mostly through impairment of nerve conduction and sometimes through respiratory arrest. Thus, the option is correct.

Question 36. Allethrin is a commonly used

1. Fertiliser
2. Herbicide
3. Growth hormone
4. Insecticide

Answer: 4. Insecticide

The allethrins are a group of related synthetic compounds used as insecticides. Allethrin was the first pyrethroid. They are commonly used in ultra-low volume sprays for outdoor mosquito control, including many household insecticides such as raid as well as mosquito coils.

Question 37. Which of the following is bioinsecticide?

1. Ladybirds beetle
2. Dragonflies
3. Bees
4. Both (1) and (2)

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

Ladybird beetles control aphids, whereas dragonflies control mosquitoes. Bees have no role as bioinsecticides.

Question 38. Ladybird beetle is a predator of

1. Moths
2. Beetles
3. Bacteria
4. Aphids

Answer: 4. Aphids

There are many species of ladybird beetles, also referred to as ladybeetles or ladybugs. Ladybird beetle is a predator of aphids, spiders, mites, scale insects, white flies, leaf beetle larvae, some insect eggs, and small caterpillars.

NEET Biology Mcq

Question 39. Meliantiol and galanin bioinsecticides have been extracted from

1. Chrysanthemum cinerariifolium
2. Derris elliptica
3. Azadirachta indica
4. Eichhornia

Answer: 3. Azadirachta indica

The neem (Azadirachta indica) is one of the best sources of the most useful natural insecticides. Natural insecticides, for example. Azadirachtin, mediation, salanin, etc., Are extracted from neem. These are very effective as insecticides as well as insect repellents and antifeedants.

Question 40. The biocontrol of larvae of mosquitoes is done by

1. Ladybird beetles
2. Gambusia fish
3. Eichhornia
4. Azolla

Answer: 2. Gambusia fish

Effective biocontrol agents include predatory fish that feed on mosquito larvae such as mosquito fish, gambusia affinis, and some cyprinids, carps, and minnows.

41. Biopesticides are

1. The chemicals which are used to destroy pests
2. The living organism or their products which are used for pest control
3. The organism which destroys crops
4. None of the above

Answer: 2. The living organism or their products that are used for pest control

Biopesticides are less harmful than conventional pesticides. They are biological control agents which are used to control weeds and pests. They are of two types, i.e. Bioherbicides, and bioinsecticides.

Question 42. A fungal pesticide, beauvericin bassiana is used to kill

1. Whiteflies and mites
2. Larvae of Aedes
3. Larvae of mosquitoes
4. Cacti

Answer: 1. White flies and mites

Beauveria bassiana can be used as a biological insecticide to control a number of pests such as termites, white flies, and many other insects.

Question 43. A viral pesticide used against gypsy moths is

1. Npv
2. Nosema locustae
3. Fusarium
4. Beauveria bassiana

Answer: 1. NPV

Npv, i.e. Nucleopolyhedrovirus is a baculovirus that is a viral pesticide used against gypsy moths, aphids, and beetles.

Question 44. Which of the following is not a correctly matched pair?

1. Azadirachtin–neem
2. Nicotine–tobacco
3. Pyrethrum–datura
4. Rotenone–derris elliptical

Answer: 3. Pyrethrum–datura

Matched pair and can be corrected as pyrethrum is obtained from chrysanthemum. Rest options are correctly matched pairs.

Question 45. In the USA, the return of brown pelican is the result of banning the use of which pesticide?

1. 2, 4-D
2. Ddt
3. Bordeaux mixture
4. Malathion

Answer: 2. Ddt

• There has been a decline in the number of ospreys and bald eagles along the eastern coast of the united states due to DDT pesticide contamination. Ddt reaches these birds through biomagnification.
• It makes their eggs non-viable, as the disturbed calcium metabolism in these birds causes the formation of eggs with fragile shells. So, brown pelican populations recovered after the banning of most uses of ddt.

NEET Biology Mcq

Question 46. Consider the following statements.

1. Biocontrol refers to the use of biological methods for controlling plant diseases and pests.
2. The use of biocontrol measures greatly reduces our dependence on toxic chemicals and pesticides.

Choose the correct option.

1. Statement 1 is correct, but 2 is incorrect
2. Statement 1 is incorrect, but 2 is correct
3. Both statements 1 and 2 are correct
4. Both statements 1 and 2 are incorrect

Answer: 3. Both statements 1 and 2 are correct

Question 47. Consider the following statements about bt.

1. The bacteria Bacillus thuringiensis (Bt) is used to control butterfly caterpillars.
2. Fresh spores of bt are mixed with water and sprayed on plants such as brassica and fruit trees.
3. Insect larvae after eating, but spores are killed by the toxin released in their gut.
4. Bt toxin genes have been introduced into animals to prey on pests.

Choose the option containing the correct statements.

1. 1, 2 And 3
2. 1, 3 And 4
3. 2, 3 And 4
4. 1, 2, 3 And 4

Answer: 1. 1, 2 And 3

All given statements are correct except iv. Thus, the option is correct. Bt toxin genes have been introduced into plants so as to kill insect pests. Thus, an option is correct.

Biology MCQ For NEET With Answers Microbes In Human Welfare

Question 1. Identify the habitat of microorganisms.

1. Soil, air, water and inside the bodies of living organisms
2. Thermal vents deep in the soil
3. Under snow as well as the acidic environment
4. All of the above

Answer: 4. All of the above

Microbes can be found everywhere, i.e. In soil, water, air and inside the bodies of living organisms. They can be found in thermal vents deep in the soil, under snow as well as in acidic environments.

Question 2. Which of the following microbes play an important role in converting milk into curd?

1. Bacteria
2. Virus
3. Fungi
4. Protozoa

Answer: 1. Bacteria

In the process of making curd, bacteria convert milk into curd and milk protein into predigest milk protein.

Read And Learn More: NEET Biology Multiple Choice Question And Answers

Question 3. Identify the correct statement.

1. Microorganism like lactobacillus is commonly called the lab
2. The lab is widely used in food fermentation
3. Lab has the ability to improve the flavour of food products
4. All of the above

Answer: 4. All of the above

Microorganism such as lactobacillus is commonly called lactic acid bacteria (lab). These bacteria are widely used in food fermentation because of their ability to improve the flavours, texture and safety of perishable raw materials such as milk, meat and vegetables.

Question 4. Which of the following bacteria convert milk into curd?

1. Propionibacterium shermanii
2. Saccharomyces cerevisiae
3. Lactobacillus
4. Thermophilic bacteria

Answer: 3. Lactobacillus

Lactic acid bacteria (lab) like lactobacillus are added to milk. It converts the lactose sugar of milk into lactic acid. Lactic acid causes coagulation and partial conversion of milk protein casein to paracaesinate. Thus, milk is changed into curd, yoghurt and cheese.

Question 5. Curd is formed by adding a small amount of curd to milk. This small amount is referred to as

1. Starter
2. Inoculum
3. Both (1) and (2)
4. None of the above

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

Curd is formed by adding a small amount of curd to milk. This small amount of curd is referred to as a starter or inoculum. The starter or inoculum used in the preparation of milk products actually contains millions of lactic acid bacteria (lab).

Biology MCQ For NEET With Answers

Question 6. Consider the following statements about the lab.

1. It increases the vitamin 12 amount, thus increasing the nutrient quality of milk.
2. It checks disease-causing microbes in the stomach.

Choose the correct option.

1. Statement 1 is correct, but 2 is incorrect
2. Statement 1 is incorrect, but 2 is correct
3. Both statements 1 and 2 are correct
4. Both statements 1 and 2 are incorrect

Answer: 3. Both statements 1 and 2 are correct

• Both statements 1 and 2 are correct. A small amount of curd added to the fresh milk as inoculum or starter contains millions of lab, which at suitable temperatures multiply, thus converting milk to curd.
• It improves its nutritional quality by increasing vitamin B₁₂. In our stomach too, the lab plays a very beneficial role in checking disease-causing microbes.

Question 7. Lactic acid coagulates and partially digests the milk protein …………… During the curdling of milk.

1. Casein
2. Albumin
3. Serum
4. Lactoferrin

Answer: 1. Casein

Lactic acid bacteria (lab) like lactobacillus are added to milk. It converts the lactose sugar of milk into lactic acid. Lactic acid causes coagulation and partial conversion of milk protein casein to paracaesinate. Thus, milk is changed into curd, yoghurt and cheese.

Biology MCQ For NEET With Answers

Question 8. …A… Released by the lab during growth coagulate and partially digest …b… Here, A and B refer to

1. A–acid, b–milk protein
2. A–base, b–harmful bacteria
3. A–enzyme, b–milk protein
4. A–bacteria, b–other microbes

Answer: 1. A–acid, b–milk protein

Question 9. The starter or inoculum is added to the fresh milk in order to convert milk into curd. The term starter or inoculum here refers to

1. Bacteria rich in vitamin B₁₂
2. Bacteria rich in protein
3. Liquid containing millions of lab
4. The fresh milk

Answer: 3. Liquid containing millions of lab

Curd is formed by adding a small amount of curd to milk. This small amount of curd is referred to as a starter or inoculum. The starter or inoculum used in the preparation of milk products actually contains millions of lactic acid bacteria (lab).

 

Question 10. An enzyme used in cheese-making is

1. Protease
2. Rennet
3. Glucoamylase
4. Lactase

Answer: 2. Rennet

Rennet is extracted from the stomach of the calf and is used to prepare cottage cheese.

Question 11. Toddy is

1. A traditional drink of southern India.
2. Made by fermentation of sap from palm trees by bacteria.

Which of the statements given above about toddy is/are correct?

1. Only 1
2. Only 2
3. 1 And 2
4. None of these

Answer: 3. 1 And 2

Both statements I and ii are correct. Toddy is a traditional drink of some parts of south India, which is made by fermentation of sap from palm trees by bacteria.

Biology MCQ For NEET With Answers

Question 12. Swiss cheese is ripened by

1. Propionibacterium shermanii
2. Penicillium roqueforti
3. Penicillium camembert
4. Streptococcus lactis

Answer: 1. Propionibacterium shermanii

Swiss cheese is characterised by large holes and it is ripened by the bacteria, propionibacterium shermanii. Penicillium roqueforti is involved in the ripening of Roquefort cheese. Camembert cheese is ripened by penicillium camembert.

Question 13. Big holes in Swiss cheese are formed as a result of

1. Machine used for making the cheese
2. A bacterium producing a large amount of carbon dioxide
3. A bacterium that is visible to the naked eyes
4. A fungus that produces large amounts of carbon dioxide

Answer: 2. A bacterium producing a large amount of carbon dioxide

Large holes in Swiss cheese are formed by the CO₂ produced (causing holes) by a bacterium called Propionibacterium shermanii.

Question 14. In cheese manufacturing, microorganisms are used

1. Only for souring of milk
2. Only for ripening
3. Both (1) and (2)
4. To prevent spoilage

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

During cheese production, lactic acid bacteria help in souring milk. Ripening of cheese is done by bacteria (propionibacterium shermanii) or moulds (penicillium roqueforti). So, the microorganisms are used for souring milk and ripening in cheese manufacturing.

Biology MCQ For NEET With Answers

Question 15. Conversion of milk to curd improves its nutritional value by increasing the amount of

1. Vitamin-D
2. Vitamin-E
3. Vitamin-B₁₂
4. Vitamin-A

Answer: 3. Vitamin-b12

Milk is converted to curd by certain bacteria called lactic acid bacteria. These bacteria, during the process of curdling milk, also increase its nutritive value by increasing the content of vitamin B₁₂

Question 16. What makes Idli soft and puffy?

1. A blending of idli batter
2. Addition of baking soda into idli batter
3. Bubbles of co 2 produced by microorganisms
4. Addition of lactobacilli culture

Answer: 3. Bubbles of co 2 produced by microorganisms

In the preparation of idli batter, the batter is fermented using bacteria or yeast. During fermentation, CO₂ bubbles which are released get trapped in the gluten, thus making idli soft and puffy.

Question 17. Which gas is released during the process of fermentation of dough giving it a puffy appearance?

1. CO₂
2. CO
3. O₂
4. _H2

Answer: 1. CO₂

CO₂ gas is released during the process of fermentation. It gives a puffy appearance to a dough.

Question 18. The dough in bread making is fermented by

1. Bacteria
2. Virus
3. Prions
4. Yeast

Answer: 4. Yeast

The dough used for making bread is fermented by saccharomyces cerevisiae or commonly called baker’s yeast. Co2 released during the process of fermentation gives a puffy appearance to the dough. It is used to make foods like idli, dosa, bread, etc.

Biology MCQs with answers for NEET

Question 19. What is used in the production of leavened bread?

1. Aspergillus
2. Rhizopus
3. Saccharomyces
4. None of the above

Answer: 3. Saccharomyces

• Saccharomyces is used in the production of leavened bread. The dough used for making bread is fermented by saccharomyces cerevisiae or commonly called baker’s yeast.
• CO₂ released during the process of fermentation gives a puffy appearance to the dough. It is used to make foods like idli, dosa, bread, etc.

Question 20. Assertion yeasts such as saccharomyces cerevisiae are used in the baking industry.

Reason (R) Carbon dioxide produced during fermentation causes bread dough to rise by thermal expansion.

1. Both a and r are true and r is the correct explanation of a
2. Both a and r are true, but r is not the correct explanation of a
3. A is true, but r is false
4. Both a and r are false

Answer: 1. Both a and r are true and r is the correct explanation of a

• Both a and r are true and r is the correct explanation of a the dough used for making bread is fermented by saccharomyces cerevisiae or commonly called baker’s yeast.
• CO₂ released during the process of fermentation gives a puffy appearance to a dough. It is used to make foods like idli, dosa, bread, etc.

Question 21. Which of the following food items undergo fermentation?

1. Idli
2. Dosa
3. Toddy
4. Cheese

Choose the correct option.

1. 1, 2 And 3
2. 1, 3 And 4
3. 2, 3 And 4
4. 1, 2, 3 And 4

Answer: 4. 1, 2, 3 And 4

• All given food items undergo fermentation. Idli and dosa are fermented preparation of rice and black gram. The two are allowed to ferment for 3-12 hours with airborne leuconostoc and streptococcus species of bacteria.
• Toddy is a traditional drink of some parts of south India, which is made by fermentation of sap of palms by bacteria. Cheese is formed by the partial degradation of milk by different microorganisms.

Biology MCQs with answers for NEET

Question 22. The fungus involved in the ripening of Roquefort cheese gives it the unique

1. Colour
2. Flavour
3. Shape
4. Texture

Answer: 2. Flavour

Roquefort cheese is formed by ripening with the fungi penicillium roqueforti, for a particular flavour.

Question 23. Roquefort cheese is obtained by ripening with the fungi

1. Propionibacterium shermanii
2. Penicillium roqueforti
3. Propionibacterium roqueforti
4. Penicillium Sherman

Answer: 2. Penicillium roqueforti

Roquefort cheese is formed by ripening with the fungi penicillium roqueforti, for a particular flavour.

Question 24. Match the following columns.

Answer: 1. A–4, b–3, c–2, d–1

Question 25. Pasteurisation is a process that is undertaken to

1. Kill all microbes
2. Kill the pathogenic microbes
3. Make milk tastier
4. Make beverages

Answer: 2. Kill the pathogenic microbes

Pasteurisation is a process that is undertaken to kill all pathogenic microbes. Methods of pasteurisation of milk used commercially include a low-temperature holding (lth) method and a high-temperature short-time (test) method. The first process employs equipment capable of exposing milk to a temperature.

Question 26. Consider the following statements.

1. Pasteurisation alters the taste of food products.
2. The process of pasteurisation is named after Louis Pasteur.

Choose the correct option.

1. Statement 1 is correct, but 2 is incorrect
2. Statement 1 is incorrect, but 2 is correct
3. Both statements 1 and 2 are correct
4. Both statements 1 and 2 are incorrect

Answer: 2. Statement 1 is incorrect, but 2 is correct

• Statement 1 is incorrect, but 2 is correct. The incorrect statement can be corrected as pasteurisation is a process whereby fluids such as wine and milk are heated for a predetermined time at a temperature that is below the boiling point of the liquid.
• The treatment kills any microorganisms that are in the fluid but does not alter the taste, appearance, or nutritive value of the fluid.
• The process of pasteurisation is named after the French chemist Louis Pasteur (1822–1895), who is regarded as the founder of the study of modern microbiology.

Biology MCQs with answers for NEET

Question 27. Pasteurised milk is

1. Sterile and do not turn sour
2. Free from pathogenic bacteria
3. Not free from bacteria
4. Both (1) and (2)

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

Pasteurised milk is considered to be healthy for a person to consume as the process kills disease-causing germs, such as campylobacter, e. Coli and salmonella from milk. Pasteurisation does not reduce milk’s
nutritional value but kills the pathogenic bacteria in it. Due to this, the milk does not turn sour.

Biology MCQ For NEET With Answers Microbes In The Production Of Biogas

Question 1. Biogas production from waste biomass with the help of methanogenic bacteria is

1. Multi steps process
2. One-step process
3. Two steps process
4. Three steps process

Answer: 4. Three steps process

Biogas is methane-rich fuel gas produced by the anaerobic breakdown of biomass by methanogenic bacteria. It is a three steps process.

Question 2. Both power and manure are provided by

1. Biogas plant
2. Distillation plant
3. Sugar processing plant
4. Nuclear plant

Answer: 1. Biogas plant

Biogas is used as fuel for heating cooking and lighting. Slurry remaining after the production of biogas can be used as fertilizers

Read And Learn More: NEET Biology Multiple Choice Question And Answers

Question 3. The first step in biogas production is

1. Generation of methane
2. Aerobic breakdown of polymers
3. Anaerobic breakdown of polymers
4. Conversion of monomers to organic acids

Answer: 3. Anaerobic breakdown of polymers

In the first step of biogas production, the polymer, cellulose that is present in the raw material like cow dung, is hydrolyzed to simple compounds anaerobically, i.e. Anaerobic breakdown of polymers.

Question 4. Biogas is ………….. Source of energy.

1. Conventional and non-renewable
2. Non-conventional and renewable
3. Conventional and renewable
4. Non-conventional and non-renewable

Answer: 2. Non-conventional and renewable

Biogas is considered to be a renewable and non-conventional resource because its production and use cycle is continuous and it generates no net carbon dioxide.

Question 5. The main raw material used in biogas production is

1. Vegetable waste
2. Cow dung
3. Agricultural waste
4. Domestic waste

Answer: 2. Cow dung

Cattle dung has been recognized as the chief raw material for biogas plants. Other materials like night soil, poultry litter, and agricultural waste are also used.

Question 6. Name the group of microbes observed in a biogas plant.

1. Lactic acid bacteria
2. Cyanobacteria
3. Both (1) and (2)
4. Methanogens

Answer: 4. Methanogens

Certain bacteria which grow anaerobically on cellulosic material, produce large amounts of methane along with carbon dioxide and hydrogen gas. These bacteria are collectively called methanogens. They are used in biogas plants.

Question 7. Which of the following wastes are used in biogas production?

1. Domestic waste, agricultural waste
2. Agro waste, municipal waste
3. Forestry waste
4. Chemical waste

Choose the option containing

1. 1 And 4 are used
2. 2 And 3 are used
3. 1, 2, And 3 are used
4. 2 And 4 are used

Answer: 3. 1, 2 And 3 are used

Except for chemical wastes, all the organic waste like domestic, agricultural, municipal, forestry, etc. Waste can all be used in biogas production.

8. The diagram below represents a typical biogas plant. Select the correct option for a, b, c, and d, respectively.

1. A–sludge, b–dung+water, c–gas tank, d–outlet
2. A–gas tank, b–dung+water, c–sludge, d–inlet
3. A–sludge, b–digester, c–an inlet of dung and water, d–gas tank
4. A–gas tank, b–sludge, c–dung + water, d–inlet

Answer: 3. A–sludge, b–digester, c–an inlet of dung and water, d–gas tank

Question 9. During anaerobic digestion of organic waste, such as in producing biogas, which of the following is not degraded?

1. Hemicellulose
2. Cellulose
3. Lipids
4. Lignin

Answer: 4. Lignin

Lignin does not degrade in the production of biogas.

Question 10. Biogas production is an

1. Aerobic process
2. Anaerobic process
3. Active process
4. None of the above

Answer: 2. Anaerobic process

Biogas generation is a three-stage process of anaerobic digestion of animal and other organic wastes by methanogenic bacteria.

Biology MCQ For NEET With Answers

These are.

1. Breakdown of polymers.
2. Conversion of monomers into organic acids by fermentation of microbes.
3. Generation of methane by methanogenic bacteria (conversion of organic acids into ch4 and CO₂).

Question 11. In a biogas plant, a mixture of cow dung and water is fed in the ratio of

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

Answer: 2. 1:1

• The mixture of dung and water which enters the biogas plant in semiliquid form is called ‘undigested slurry.’ It contains cow dung and water in a 1:1 ratio.
• The undigested slurry undergoes a series of anaerobic digestion processes or fermentation in a biogas digester and is converted into a combustible gas called ‘biogas.’

Question 12. The anaerobic digestion of biogas production involves

1. Conversion of insoluble polymers to simple soluble monomers
2. Conversion of monomers to organic acids
3. Conversion of organic acids to methane
4. Conversion of monomers to methane

Answer: 1. Conversion of insoluble polymers to simple soluble monomers

Anaerobic digestion is the process by which insoluble polymers of organic matter such as animal or food waste are broken down into simple soluble monomers to produce biogas and biofertiliser. This process happens in the absence of oxygen in a sealed, oxygen-free tank called an anaerobic digester.

Question 13. For biogas production, besides dung which one of the following weed is recommended in our country?

1. Eichhornia crassipes
2. Hydrilla
3. Mangifera
4. Solanum nigrum

Answer: 1. Eichhornia crassipes

Eichhornia crassipes is recommended because of its extremely high rate of development. It is an excellent source of biomass. The harvested biomass would then be converted to ethanol, natural gas, hydrogen or gaseous nitrogen, and fertilizer.

Biology MCQ For NEET With Answers

Question 14. The ph at which methane is produced by bacteria is

1. Neutral
2. Acidic
3. Alkaline
4. All of these

Answer: 2. Acidic

In the second stage of biogas formation, acetogenic bacteria form organic acids such as acetic or propionic acid which are further converted to methane. Hence, methane formation takes place in acidic ph.

15. Household sewage mainly contains large amounts of …A… And …B… The most suitable answer is

1. A–excreta, b–vegetable waste
2. A–organic matter, b–pathogenic microbes
3. A–inorganic matter, b–virus
4. A–non-decomposable matter, b–water

Answer: 2. A–organic matter, b–pathogenic microbes

Sewage contains large amounts of organic matter and pathogenic microbes (b).

Question 16. Study the following flowchart of biogas production and select the correct option for a, b and c

1. A–methanogenic bacteria, b–fermentative microbes, c–hydrogen (biogas)
2. A–fermentative microbes, b–methanogenic bacteria, c–methane (biogas)
3. A–anaerobic microorganisms, b–echinococcus, c–nitrogen (biogas)
4. A–aerobic microorganism, b–methanobacter, c–methane (biogas)

Answer: 2. A–fermentative microbes, b–methanogenic bacteria, c–methane (biogas)

Question 17. Biogas is composed of a mixture of inflammable gases like

1. Methane, CO_2, H_{2, and} H₂S
2. Methane, CO_2, H_{2, and} N₂
3. CO_2, H_{2, and} H₂S
4. CO, methane, and N₂

Answer: 1. Methane, CO_2, H_{2, and} H₂S

The major component of biogas is methane (which is highly inflammable), CO_2, H_{2, and} H₂S

Biology MCQs with answers for NEET

Question 18. Biogas contains

1. 10-30% Methane
2. 30-40% Methane
3. 50-80% Methane
4. 80-90% Methane

Answer: 3. 50-80% Methane

Biogas is produced by anaerobic fermentation of biomass. It consists of 50-80% methane, 15- 45% co2, and traces of hydrogen, oxygen, and nitrogen.

Question 19. The proportion of methane and carbon dioxide in biogas is about

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

Answer: 1. 2: 1

Biogas contains about 70% methane and about 40% carbon dioxide. Thus, the approximate ratio is about 2:1.

Question 20. Methanogens do not produce

1. Nitrogen
2. Methane
3. Hydrogen sulfide
4. Carbon dioxide

Answer: 1. Nitrogen

Methanogens derive energy by converting carbon dioxide, hydrogen, formate, acetate, and other compounds from the organic matter of peat to methane. They do not produce nitrogen.

Question 21. Consider the following statements about methanogens.

1. Methanogen bacteria are commonly found in the anaerobic sludge formed during sewage treatment.
2. These bacteria occur in the rumen of cattle where they break down cellulose.
3. Methanogens are present in harsh environments such as hydrothermal vents.

Choose the option containing

Correct statements.

1. 1, 2 And 3
2. 1 And 2
3. 1 And 3
4. 2 And 3

Answer: 1. 1, 2 And 3

• All the given statements are correct about methanogens. Methanogens, particularly methanobacterium, anaerobically break down cellulosic material to produce hydrogen that can be used in methanogenesis.
• These are found in anaerobic sludge and rumen of cattle. Thermophilic methanogens are found in hydrothermal vents at temperatures between 55°c-80°c.

NEET Biology Mcq

Question 22. Pollution from animal excreta and organic waste from kitchens can be most profitably minimized by

1. Storing them in underground storage tanks
2. Using them for producing biogas
3. Vermiculture
4. Using them directly as biofertilizers

Answer: 2. Using them for producing biogas

• Pollution from human excreta and organic wastes from the kitchen can be most profitably minimized by using them for producing biogas.
• These wastes release methane and other gases, as a result of the action of anaerobic microorganisms. Biogas contains methane in bulk and other gases like h s2 and h2.

Question 23. Biogas plant is not popular in an urban area because

1. It has a foul smell
2. Raw materials are not easily available
3. Biogas is highly inflammable
4. Biogas manufacturing plant is costly

Answer: 2. Raw materials are not easily available

Biogas production has been taken up on a large scale in India, whereas in urban areas it is not so popular because the raw material used is not easily available.

Question 24. Which one of the following statements is incorrect about biogas?

1. It contains 50-80% methane
2. Agricultural wastes are utilized
3. It is highly polluting
4. Biogas plant is difficult to construct

Answer: 3. It is highly polluting

Biogas mostly consists of 50-70% methane. It burns with a blue flame and does not produce smoke. Thus, it is not polluting. Rest statements are correct about biogas.

NEET Biology Mcq

Question 25. Which of the following aquatic weeds is not used in the production of biogas?

1. Eichhornia crassipes
2. Hydrilla
3. Pistia stratiotes
4. Spirulina

Answer: 4. Spirulina

Spirulina is a blue-green algae used as a source of valuable food specifically for proteins. It is not used in the production of biogas.

Question 26. Assertion biogas is used as fuel for cooking and lighting.

Reason (R) is considered an eco-friendly and non-polluting source of energy.

1. Both a and r are true and r is the correct explanation of a
2. Both a and r are true, but r is not the correct explanation of a
3. A is true, but r is false
4. Both a and r are false

Answer: 2. Both a and r are true, but r is not the correct explanation of a

Both a and r are true, but r is not the correct explanation of a. Biogas is a mixture of inflammable gases due to which it is used as fuel for cooking, lighting, generating power for irrigation, and other purposes, as an alternative to firewood, kerosene, dung cakes or even electricity. It is an eco-friendly and pollution-free source of energy.

Question 27. The technology of biogas production from cow dung was developed in India largely by the efforts of the organization/institution that played a great role in developing a technology of producing biogas from cow dung in India was

1. Oil and natural gas commission
2. Gas Authority of India
3. Indian agricultural research institute and khadi and village industries commission
4. Indian oil corporation

Answer: 3. Indian agricultural research institute and khadi and village industries commission

Biogas or gobar gas generation has been taken up in India on a large scale. The technology was developed by the collaboration of the Khadi and village industries commission (kvic) and the Indian agricultural research institute.

Question 28. Which of the following is not an advantage of biogas?

1. It is cheap
2. A large quantity of raw material is required
3. It does not cause pollution
4. It is used for cooking and lighting

Answer: 2. Large quantity of raw material is required

Producing biogas gives many advantages for the environment, companies, and people involved. The advantages are

1. Biogas is a green energy source in the form of electricity and heat for the local grid.
2. Less emission of the greenhouse gasses like methane, co2 and nitrous oxide. So, biogas does not cause pollution.
3. Environment-friendly recirculation of organic waste from industry and households. So, biogas is cheap.
4. Less odour inconveniences when spreading slurry on the fields. The fermented slurry smells considerably less than normal slurry and the smell decreases faster.

Biology MCQs with answers for NEET Microbes In Industrial Products

Question 1. Which organism is responsible for alcoholic fermentation?

1. Chlorella
2. Yeast
3. Agaricus
4. Puccinia

Answer: 2. Yeast

Alcoholic fermentation is carried out by yeast. It converts sugars to ethanol, CO₂ and other metabolic byproducts.

Question 2. Saccharomyces cerevisiae is used in the commercial production of

1. Butanol
2. Ethanol
3. Methanol
4. Yeast

Answer: 2. Ethanol

Saccharomyces cerevisiae is used in the commercial production of ethanol. It is a single-celled eukaryotic budding yeast belonging to the ascomycetes (a highly diverse group of fungi).

Read And Learn More: NEET Biology Multiple Choice Question And Answers

Question 3. Which one of the following enzymes is secreted by yeast for fermentation?

1. Enolase
2. Invertase
3. Zymase
4. Dehydrogenase

Answer: 3. Zymase

Zymase is secreted by yeast for fermentation. It is a mixture of enzymes obtained from yeast which catalyse the breakdown of sugars in alcoholic fermentation.

Question 4. Identify the organism used in the production of beverages like wine, beer, whisky, brandy or rum.

1. Clostridium bretylium
2. Aspergillus niger
3. Saccharomyces cerevisiae
4. Penicillium notatum

Answer: 3. Saccharomyces cerevisiae

Beverages are formed by fermenting malted cereals and fruit juices with saccharomyces cerevisiae or brewer’s yeast to produce ethanol.

Question 5. Brewer’s yeast is

1. Aspergillus fumigatus
2. Saccharomyces cerevisiae
3. Streptomyces griseus
4. Clostridium botulinum

Answer: 2. Saccharomyces cerevisiae

Yeast species used in alcoholic fermentation is s. Cerevisiae. So, brewer’s yeast is saccharomyces cerevisiae.

Biology MCQs with answers for NEET

Question 6. The conversion of sugar into alcohol during fermentation is due to the direct action of

1. Temperature
2. Microorganisms
3. The concentration of sugar solution
4. Zymase

Answer: 4. Zymase

Conversion of sugar into alcohol directly is found in yeast fermentation in which glucose is converted to ethyl alcohol and CO₂. The conversion occurs in the presence of an enzyme called zymase which is found naturally in yeast.

Question 7. A non-distilled alcoholic beverage produced by using grain mash fermentation is

1. Beer
2. Rum
3. Curd
4. Wine

Answer: 1. Beer

A non-distilled alcoholic beverage produced from grain mash fermentation is beer. Beer has an alcoholic content of 3-6%.

Question 8. Which step is not involved in beer production?

1. Malting and mashing
2. Fermentation
3. Clarification and carboxylation
4. Distillation

Answer: 4. Distillation

• Distillation is not involved in beer production. Brewing is the process of production of malt beverages, for example, beer. It is a complex fermentation process.
• It differs from other industrial fermentation because flavour, aroma, clarity, colour, foam production, foam stability and percentage of alcohol are the factors associated with the finished product.

Question 9. Whisky is obtained by fermenting

1. Jowar and banjara
2. Groundnut and jowar
3. Barley, rye, maize
4. Milletes, oats

Answer: 3. Barley, rye, maize

Whisky or whiskey is a type of distilled alcoholic beverage made from fermented grain mash. Various grains (which may be malted) are used for different varieties, including barley, corn, rye, maize and wheat.

Question 10. The distillation process is involved in

1. Production of beer
2. Production of wine
3. Production of whisky
4. Both (1) and (2)

Answer: 3. Production of whisky

The distillation process is involved in the production of whisky. It is not involved in the making of wine and beer.

Question 11. Match the following columns.

Answer: 1. A–1, 2; b–3, 4, 5

Question 12. What are the important products of yeast fermentation?

1. Ethanol and acetic acid
2. Butanol, glycerol and pyruvic acid
3. Phenylethanol, amyl alcohol and caproic acid
4. All of the above

Answer: 4. All of the above

By fermentation, the yeast species saccharomyces cerevisiae converts carbohydrates to carbon dioxide, acetic acid and alcohols like ethanol, butanol, phenyl ethanol and amyl alcohol. Yeast produces caproic acid by the fermentation of corn.

Biology MCQs with answers for NEET

Question 13. The first antibiotic was discovered in the year

1. 1928
2. 1914
3. 1980
4. 1930

Answer: 1. 1928

Penicillin was the first antibiotic to be discovered by alexander fleming in 1928.

Question 14. Most of the antibiotics are extracted from

1. Algae
2. Virus
3. Bacteria
4. Plants

Answer: 3. Bacteria

Most antibiotic drugs today are variations of substances that were originally isolated from bacteria or fungi. Penicillin is produced by a fungus, whereas streptomycin, chloramphenicol and tetracycline, are produced by soil bacteria.

Question 15. The highest number of antibiotics are produced by

1. Bacillus
2. Penicillium
3. Streptomyces
4. Cephalosporium

Answer: 3. Streptomyces

Many of the most important antibiotics used in hospitals around the world come from streptomyces bacteria. They are valued by scientists because they produce a variety of ‘secondary metabolites’ chemicals that help the bacteria prosper by inhibiting rival microbes.

Biology MCQs with answers for NEET

Question 16. The term ‘antibiotic’ was first coined by

1. Fleming
2. Pasteur
3. Waksman
4. Lister

Answer: 3. Waksman

• The chemical substances produced by some microbes which can kill or retard the growth of other microbes are called antibiotics.
• The term antibiotic was first coined by Waksman (1942). Penicillin was the first antibiotic to be discovered by alexander fleming (1928).

Question 17. Which one of the following is not an antibiotic?

1. Streptomycin
2. Citric acid
3. Griseofulvin
4. Cephalosporin

Answer: 2. Citric acid

Citric acid is obtained through the fermentation carried out by Aspergillus niger and mucor species on sugary syrups. It is not an antibiotic.

Question 18. The property of antibiotics to kill pathogenic microorganisms is called

1. Bacteriogenesis
2. Angiogenesis
3. Antibiosis
4. Antibiogenesis

Answer: 3. Antibiosis

Antibiosis is defined as an antagonist association between an organism (especially a microorganism) and the metabolic substances produced by another. This property of antibiotics is widely used to kill pathogenic microorganisms.

Question 19. Antibiotics are Kerala

1. Drugs to kill viruses
2. Toxins produced by bacteria
3. Products of bacterial metabolism
4. Both (2) and (3)

Answer: 4. Both (2) and (3)

Antibiotics are toxic chemical substances produced by bacteria during bacterial metabolism. These chemicals are used to kill pathogenic microorganisms, particularly bacteria. These do not act against viruses.

Biology MCQ For NEET With Answers

Question 20. Antibiotics are used in the treatment of diseases like

1. Diphtheria, whooping cough
2. Plague
3. Leprosy
4. All of the above

Answer: 4. All of the above

Antibiotics are used as medicines for the treatment of a number of pathogenic bacterial diseases, e.g. Plaque, typhoid, tuberculosis, whooping cough, diphtheria, leprosy, etc.

Question 21. Streptomycin and actinomycin were discovered by

1. Waksman
2. Woodruff
3. Fleming and Waksman
4. Waksman and woodruff

Answer: 1. Waksman

Streptomycin and actinomycin were discovered by American biochemists Selman Waksman, Albert Schatz and Elizabeth Bugie in 1943.

Question 22. Which antibiotic was extensively used to treat American soldiers wounded in world war ii?

1. Streptokinase
2. Penicillin
3. Statins
4. Neomycin

Answer: 2. Penicillin

In 1940, e chain and h Florey obtained a relatively stable preparation of penicillin, which was extensively used to treat wounded American soldiers in World war-ii.

Question 23. Antibiotics of fungal origin are

1. Penicillin
2. Cephalosporin
3. Both (1) and (2)
4. Gentamicin

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

The first antibiotic to be mass-produced was penicillin, derived from the fungi, penicillium. The cephalosporins were first isolated from cultures of the fungus Cephalosporium acremonium.

Question 24. Rhizopus nigricans is used in the production of

1. Citric acid
2. Gluconic acid
3. Fumaric acid
4. Acetic acid

Answer: 2. Gluconic acid

Rhizopus nigricans (mucor stolonifer) and some aspergilli are able to form fumaric acid.

Biology MCQ For NEET With Answers

Question 25. Statins used as blood cholesterol-lowering agents are extracted from

1. Algae
2. Yeast
3. Virus
4. Bacteria

Answer: 2. Yeast

Statins are products of the fermentation activity of yeast monascus purpureus. They are used in lowering blood cholesterol. Statins competitively inhibit enzymes for cholesterol synthesis.

Question 26. Bioactive molecules produced from monascus purpureus which inhibit cholesterol synthesis in blood are

1. Gluconic acid
2. Statins
3. Gibberellins
4. Bacitracin

Answer: 2. Statins

Statins are products of the fermentation activity of yeast monascus purpureus. They are used in lowering blood cholesterol. Statins competitively inhibit enzymes for cholesterol synthesis.

Question 27. Identify the microbe used in the commercial production of butyric acid.

1. Clostridium bretylium
2. Streptococcus bretylium
3. Trichoderma polysporum
4. Saccharomyces cerevisiae

Answer: 1. Clostridium bretylium

Clostridium butylicum is used in the commercial production of butyric acid.

Question 28. Cyclosporin-a, used as an immunosuppression agent is produced from

1. Saccharomyces purpureus
2. Monascus purpureus
3. Penicillium notatum
4. Trichoderma polysporum

Answer: 4. Trichoderma polypore

Cyclosporin-a is an eleven-membered cyclic oligopeptide obtained through the fermentative activity of the fungus Trichoderma polypore. It inhibits the activation of t-cells and therefore prevents rejection reactions in organ transplantation.

Question 29. Identify the blank spaces a, b, c and d given in the following table and select the correct answer. Type of microbe → scientific name → commercial product bacterium → a → lactic acid → fungus → b → cyclosporin-a → c→ monascus purpureus → d → fungus → e → penicillin

1. A–lactobacillus, b–Trichoderma polypore, c–yeast, d–statins, e–Penicillium notatum
2. A–staphylococcus, b–clostridium, c–yeast, d–penicillin, e– Penicillium notatum
3. A–lactobacillus, b–Microsporum, c–plant, d–yeast, e–Trichoderma polypore
4. A–staphylococcus, b–Microsporum, c–Agaricus, d–penicillin, e–lactobacillus

Answer: 1. A–lactobacillus, b–Trichoderma polypore, c–yeast, d–statins, e–Penicillium notatum

Biology MCQ For NEET With Answers

Question 30. The utility of fungi for steroid conversion was demonstrated by

1. Kohler and Milstein
2. Murray and Peterson
3. Kornberg and miller
4. Waksman and Monod

Answer: 2. Murray and Peterson

Murray and Peterson demonstrated the utility of fungi for steroid conversion by using the Rhizopus stolonifera

Question 31. Match column 1 and column 2 and choose the correct option from the codes given below.

Codes

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

Answer: 1. A–4, b–3, c–2, d–1

Question 32. During the production of tea, the flavouring of leaves is done with the help of

1. Bacillus subtilis
2. B. Aceti
3. B. Megatherium
4. B. Radicicola

Answer: 3. B. Megatherium

The flavouring of tea leaves is done by Bacillus megatherium. It is isolated from tea rhizospheres which help to solubilize phosphate and promotes the growth of tea plants. It also affects sclerotial blight disease and induces systemic resistance in tea plants.

Question 33. Chloromycetin is obtained from

1. Streptomyces griseus
2. Streptomyces venezuelae
3. Bacillus subtilis
4. Saccharomyces cerevisiae

Answer: 2. Streptomyces venezuelae

Chloromycetin is an antibiotic first isolated from cultures of streptomyces venezuelae in 1947 but is now produced synthetically.

Question 34. For the commercial and industrial production of citric acid, which of the following microbe is used?

1. Aspergilus niger
2. Lactobacillus sp.
3. Saccharomyces cerevisiae
4. Clostridium bretylium

Answer: 3. Saccharomyces cerevisiae

Aspergillus niger is used to prepare citric acid.

Biology MCQ For NEET With Answers

Question 35. The enzyme which is used as a ‘clot buster’ to cure a patient suffering from myocardial infarction is

1. Rennet
2. Streptokinase
3. Proteases
4. Lipases

Answer: 2. Streptokinase

Enzyme streptokinase is used as a ‘clot buster’ for removing blood clots from the blood vessels of patients suffering from myocardial infarction.

Question 36. Match column 1 and column 2 and choose the correct option from the codes given below.

Answer: 1. A–4, b–3, c–2, d–1

Question 37. Which one of the following is a wrong match of a microbe and its industrial product?

1. Yeast – statins
2. Acetobacter aceti – acetic acid
3. Clostridium acetobutylicum – lactic acid
4. Aspergillus niger – citric acid

Answer: 3. Clostridium acetobutylicum – lactic acid

Butyric acid is produced during the fermentation activity of the bacterium Clostridium acetobutylicum. Lactic acid fermentation is carried out by Lactobacillus sp. Rest options are correctly matched pairs.

NEET Biology Mcq

Question 38. Consider the following statements.

1. The yeast used in making bread and beverages is a prokaryotic fungus.
2. Streptokinase produced by streptococcus is modified by genetic engineering and used as a clot buster.
3. Lipases are added to detergent for removing oily stains from laundry.
4. Pectinases are used in clearing fruit juices.

Choose the option containing

Correct statements.

1. 1, 2, 3 And 4
2. 1, 2 And 3
3. 2, 3 And 4
4. 3 And 4

Answer: 3. 2, 3 And 4

All given statements are correct except i. The incorrect statements can be corrected as yeast used in baking and in the preparation of alcoholic beverages is a type of eukaryotic fungus.

Question 39. Which industrial products are synthesised from microbes?

1. Antibiotics
2. Fermented beverages
3. Bioactive molecules
4. Enzymes

Choose the correct option.

1. 3 And 4
2. 2, 3 And 4
3. 1, 3 And 4
4. 1, 2, 3 And 4

Answer: 4. 1, 2, 3 And 4

All given industrial products are synthesised from microbes. Microbes are used to synthesise a number of products valuable to human beings. Beverages, antibiotics, bioactive molecules and enzymes are some examples.

Question 40. Identify the blank spaces a, b, c and d given in the following table and select the correct answer.

1. A–Trichoderma polisporum, b–yeast, c–as an immunosuppressive agent in organ transplant patients, d–as a blood-cholesterol lowering agent
2. A–Trichoderma polisporum, b–protozoa, c–as blood-cholesterol lowering agent, d–as an immunosuppressive agent in organ transplant patients
3. A–clostridium bretylium, b–yeast, c–used as a clot buster, d–as a blood-cholesterol agent
4. A–clostridium bretylium, b–yeast, c–as blood-cholesterol lowering agent, d–used as a clot buster

Answer: 1. A–Trichoderma polisporum, b–yeast, c–as an immunosuppressive agent in organ transplant patients, d–as a blood-cholesterol lowering agent

NEET Biology Mcq

Question 41. Probiotics are

1. Cancer inducing microbes
2. New kinds of food allergens
3. Live microbial food supplement
4. Safe antibiotics

Answer: 3. Live microbial food supplement

Probiotics are defined as live microorganisms, including lactobacillus species, bifidobacterium species and yeasts, that may beneficially affect the host upon ingestion by improving the balance of the intestinal microflora. These are widely used as food supplements.

Question 42. Read the following statement having two blanks a and b. A drug used for …a… Patients are obtained from a species of the organism … B…

The one correct option for the two blanks is

1. A–heart, b–penicillium
2. A–organ transplant, b–trichoderma
3. A–swine flu, b–monascus
4. A–aids, b–pseudomonas

Answer: 2. A–organ transplant, b–trichoderma

Question 43. Match the following organisms in column 1 with the products they produce in column 2.

Codes

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

Answer: 2. A–2, b–4, c–3, d–5

Question 44. Match the following columns.

Answer: 1. A–2, b–1, c–4, d–3

Question 45. Consider the following statements.

1. Antibiotics are chemical substances produced by some microorganisms, which can kill or retard the growth of other disease-causing microorganisms.
2. Penicillin is the first antibiotic to be discovered and was discovered by alexander fleming (1928) while working on the bacterium Staphylococcus aureus.
3. The function of penicillin as an antibiotic was established by Ernst Chain and Howard Florey.

Choose the option containing 

Correct statements.

1. 1 And 2
2. 1 And 3
3. 2 And 3
4. 1, 2 And 3

Answer: 4. 1, 2 And 3

• All given statements are correct. Antibiotics are chemical substances produced by some microorganisms, which can kill or retard the growth of other disease-causing microorganisms. Penicillin, discovered by alexander fleming, is the first antibiotic to be discovered.
• While working on staphylococcus aureus bacteria, Fleming observed the growth of mould around, where the bacteria did not grow.
• It was found to be a chemical penicillin, produced by penicillium notatum. The function of penicillin as an antibiotic was established by Ernst Chain and Howard Florey.

NEET Biology Mcq

Question 46. Fill up the blanks.

1. Ethanol is produced by the action of …a…
2. Large-scale fermentation in industries is carried out in large vessels called …b…
3. Penicillin was discovered by …c…
4. Lab checks disease-causing microbes in …d…

A to D in the above statements refer to

1. A–virus, b–fermenters, c–Alexander fleming, d–intestine
2. A–yeast, b–fermenters, c–Alexander fleming, d–stomach
3. A–chest, b–fermenters, c–s Waksman, d–bacteria
4. A–bacteria, b–fermenters, c–s waksman, d–liver

Answer: 2. A–yeast, b–fermenters, c–Alexander fleming, d–stomach

Biology MCQ For NEET With Answers Microbes In Sewage Treatment

Question 1. Primary treatment involves

1. Physical removal of large and small particles from sewage
2. Biological removal of large and small particles from sewage
3. Chemical removal of large and small particles from sewage
4. Both (2) and (3)

Answer: 1. Physical removal of large and small particles from sewage

Primary treatment of sewage is the process of removal of small and large, floating and suspended solids from sewage through filtration and sedimentation.

Question 2. In the primary treatment of sewage, the floating debris is removed by passing the sewage through wire mesh screens. This is known as

1. Sequential filtration
2. Sedimentation
3. Aeration
4. Evaporation

Answer: 1. Sequential filtration

In the primary treatment of sewage, the floating debris is removed by sequential filtration by passing through wire mesh.

Read And Learn More: NEET Biology Multiple Choice Question And Answers

Question 3. Which of the following in sewage treatment removes suspended solids?

1. Tertiary treatment
2. Secondary treatment
3. Primary treatment
4. Sludge treatment

Answer: 3. Primary treatment

Primary treatment of sewage is the process of removal of small and large, floating and suspended solids from sewage through filtration and sedimentation.

Biology MCQ For NEET With Answers

Question 4. Sand and small pebbles are removed in

1. Grit chambers
2. Sludge digesters
3. Aeration tank
4. Effluent tank

Answer: 1. Grit chambers

• The wastewater is passed through a screen to remove rags and large debris. The screening system washes and dewaters the debris before discharging it into a garbage cane.
• The screened wastewater then flows to an aerated grit chamber that facilitates the sedimentation of heavier inorganic materials, such as sand and grit, by reducing the velocity of the wastewater.
• The grit chamber is aerated to increase the dissolved oxygen content of the wastewater, which supports the aerobic biological process used later in the treatment system.
• The material collected at the bottom of the grit vessel is removed by an auger and mixed with biosolids generated during the treatment process. Thus, sand and small pebbles are removed in grit chambers.

Question 5. Sewage water can be purified for recycling with the action of

1. Aquatic plants
2. Penicillin
3. Microorganisms
4. Fishes

Answer: 3. Microorganisms

Microbes or microorganisms play an essential role in sewage treatment plants by decomposing organic matter both aerobically and anaerobically. They help to purify and recycle the sewage water.

Question 6. Sewage water cannot be discharged directly into rivers because

1. It contains a high level of organic matter
2. It contains pathogenic microbes
3. It may destroy the flora and fauna of the river
4. All of the above

Answer: 4. All of the above

• Sewage water cannot be discharged directly into rivers because sewage is a liquid containing organic wastes from households, industrial and agricultural activities discharged into water. It contains harmful substances and disease-causing microbes.
• All these components can adversely affect the flora and fauna of water bodies. Therefore, it is dangerous to release untreated sewage into the water.

Biology MCQ For NEET With Answers

Question 7. Secondary sewage treatment is basically

1. A chemical process
2. A physical process
3. A mechanical process
4. A biological process

Answer: 4. A biological process

Secondary treatment of the liquid effluent from the primary settling tank is purely a biological treatment, involving microbial activity.

Question 8. In the biological treatment of sewage, the mass of bacteria is held together by fungal filaments and forms a mesh-like structure called

1. Activated sludge
2. Aerobic process
3. Flocs
4. Anaerobic sludge

Answer: 3. Flocs

• Useful aerobic microbes grow rapidly and form flocs. Flocs are masses of bacteria associated with fungal filaments to form mesh-like structures.
• The growing microbes consume organic matter and thus, reduce the biochemical oxygen demand (bod).

Question 9. In sewage treatment, bacterial flocs are allowed to sediment in a settling tank. This sediment is called as

1. Activated sludge
2. Primary sludge
3. Anaerobic sludge
4. Secondary sludge

Answer: 1. Activated sludge

In sewage treatment, when the biochemical oxygen demand (body) of sewage has reduced, the effluent is passed into the settling tank. Since the sludge consists of active biological material such as flocs, it is referred to as activated sludge.

Question 10. Bod of wastewater is estimated by measuring the amount of

1. Carbon dioxide present
2. Biodegradable organic matter
3. Oxygen evolution
4. Oxygen consumption

Answer: 4. Oxygen consumption

Biochemical oxygen demand (bod) measures the amount of organic matter in water by measuring the rate of oxygen uptake (i.e. Oxygen consumption) by microbes.

Biology MCQ For NEET With Answers

Question 11. Bod is

1. Biochemical oxygen demand
2. Biological oxygen deficit
3. Biochemical oxygen deficit
4. Botanical oxygen demand

Answer: 1. Biochemical oxygen demand

Biochemical oxygen demand (bod) measures the amount of organic matter in water by measuring the rate of oxygen uptake (i.e. Oxygen consumption) by microbes.

Question 12. The purpose of biological treatment of wastewater is to

1. Reduce bod
2. Increase bod
3. Reduce sedimentation
4. Increase sedimentation

Answer: 1. Reduce bod

The growing microbes consume organic matter and thus reduce the biochemical oxygen demand (bod).

13. Good drinking water should have a body level at

1. 9-12 Ppm
2. 1-2 Ppm
3. 15-20 Ppm
4. 10.2 ppm

Answer: 2. 1-2 Ppm

• A body level of 1-2 ppm is considered very good. There will not be much organic waste present in the water supply. A water supply with a body level of 3-5 ppm is considered moderately clean.
• In water with a body level of 6-9 ppm, the water is considered somewhat polluted because there is usually organic matter present and bacteria are decomposing this waste. At body levels of 100 ppm or greater, the water supply is considered very polluted with organic waste.

14. Consider the following statements.

1. Biochemical oxygen demand (bod) represents the amount of dissolved oxygen that would be consumed if all the organic matter in 1 l of water were oxidised by microorganisms.
2. The low value of the body means the water is either normal or less polluted by organic matter.
3. The high value of the body means the water is highly polluted by organic matter.

Choose the option containing

Correct statements.

1. 1 And 2
2. 1 And 3
3. 2 And 3
4. 1, 2 And 3

Answer: 4. 1, 2 And 3

• All given statements are correct. Bod refers to the amount of oxygen consumed if all the organic matter in one litre of water is oxidised by bacteria. A body level of 1-2 ppm is considered very good.
• There will not be much organic waste present in the water supply. A water supply with a body level of 3-5 ppm is considered moderately clean.
• In water with a body level of 6-9 ppm, the water is considered somewhat polluted because there is usually organic matter present and bacteria are decomposing this waste. At body levels of 100 ppm or greater, the water supply is considered very polluted with organic waste.

Biology MCQ For NEET With Answers

15. Which of the following plan has been initiated by the Ministry of Environment and Forests to protect rivers from water pollution?

1. Ganga action plan
2. Yamuna action plan
3. Both (1) and (2)
4. Neither (1) nor (2)

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

In order to protect the major rivers of India from sewage pollution, the Ministry of Environment and Forests has initiated the development of sewage treatment plants under the national river conservation authority, Examples: Ganga action plan (gap), yamuna action plan, Sutlej Action plan, gomti action plan, etc.

Question 16. When a huge amount of sewage is dumped into a river, the body will

1. Increase
2. Remain unchanged
3. Slightly decrease
4. Decrease

Answer: 1. Increase

• When huge amounts and sewage are dumped into a river, the body will increase. Untreated sewage contains large amounts of organic matter.
• Bod is the amount of oxygen required to decompose the organic matter present in a water body. The higher the body, the more polluted the water.

Question 17. Given below is the flowchart of sewage treatment. Identify a, b, c, d and e and select the correct option.

1. A– secondary treatment, b–microbial digestion, c–high bod, d–activated sludge, e–aerobic sludge digesters
2. A–aerobic treatment, b–mechanical agitation, c–low bod, d–deactivated sludge, e–aerobic sludge digesters
3. A–small aeration tank, b–microbial digestion, c–low bod, d–activated sludge, e–anaerobic sludge digesters
4. A–secondary treatment, b–mechanical agitation, c–reduced body, d–activated sludge, e–anaerobic sludge digesters

Answer: 4. –Secondary treatment, b–mechanical agitation, c–reduced body, d–activated sludge, e–anaerobic sludge digesters

NEET Biology Mcq

Question 18. Microbes are used in

1. Primary treatment of sewage
2. Secondary treatment of sewage
3. Anaerobic sludge digesters
4. Production of biogas

Choose the correct option.

1. 1, 2 And 3
2. 1, 3 And 4
3. 2, 3 And 4
4. 1, 2, 3 And 4

Answer: 3. 2, 3 And 4

• All listed processes involve the use of microbes except primary treatment of sewage because primary treatment is the physical removal of large and small particles from sewage.
• Secondary treatment of the liquid effluent from the primary settling tank is purely a biological treatment involving microbial activity.
• In the anaerobic sludge digesters, heterotrophic microbes anaerobically digest bacteria and fungi in sludge producing a mixture of gases such as methane, hydrogen sulphide and CO₂ which form the biogas.

Question 19. During secondary treatment,

1. Primary effluent is continuously agitated in the aeration tank
2. There is vigorous growth of useful aerobic microbes into flocs
3. Reduction in body level
4. All of the above

Answer: 4. All of the above

• In the secondary treatment, the effluent is present in large effluent tanks. Air is constantly pumped and the effluent is agitated. This results in rapid growth of microbial flocs which are associations of bacteria and fungi.
• These flocs feed on the organic matter present in the effluent thereby, reducing the body. On significant reduction of body, the effluent is then passed to the settling tanks.

Question 20. What gases are produced in anaerobic sludge digesters?

1. Methane and co2 only
2. Methane, hydrogen sulphide and
3. Methane, hydrogen sulphide and o2
4. Hydrogen sulphide and co2

Answer: 2. Methane, hydrogen sulphide and

In an anaerobic sludge digester, due to the activity of anaerobic bacteria like methanogenic and sulphur bacteria, gases like ch4, h s2 and co2 are produced.

NEET Biology Mcq

Question 21. What will happen to the activated sludge floc if oxygen is reduced?

1. It will slow down the rate of degradation of organic matter
2. The centre of flocs will become anoxic resulting in death
3. Flocs would increase in size as anaerobic bacteria would grow around flocs
4. Protozoa would grow in a large number

Answer: 3. Flocs would increase in size as anaerobic bacteria would grow around flocs

Without oxygen, the microbes cannot survive. If O₂ is reduced, the centre of the flocs will become anoxic, which would cause death.

Question 22. Choose the incorrect statement about secondary sewage treatment.

1. In the settling tank, the bacterial flocs settle and the sediment is called activated sludge
2. A small part of the sludge is used as an inoculum. The remaining part is passed into anaerobic sludge digesters
3. On anaerobic digestion of bacteria and fungi, a mixture of gases such as carbon dioxide, nitrogen and carbon monoxide are produced
4. None of the above

Answer: 3. On anaerobic digestion of bacteria and fungi, a mixture of gases such as carbon dioxide, nitrogen and carbon monoxide are produced

• The statement in the option is incorrect and can be corrected as methane, hydrogen sulphide and CO₂ are the main gases produced in the digesters by the anaerobic digestion by heterotrophic bacteria and fungi.
• Carbon monoxide is not produced during this process. Rest statements are correct about secondary sewage treatment.

Question 23. Which of the following is put into an anaerobic sludge digester for further sewage treatment?

1. Floating debris
2. The effluent of primary treatment
3. Activated sludge
4. Primary sludge

Answer: 3. Activated sludge

Activated sludge is put into an anaerobic sludge digester for further sewage treatment. It contains biological flocs that contain bacteria and fungi for further digestion of organic waste.