2026 NEET Biology Questions and Answers with Explanation

1. In angiosperms, root hairs arise from which one of the following regions of the root?

a. the root cap zone

b. the region of meristematic activity

c. the region of elongation

d. the region of maturation

Answer: d. the region of maturation

Explanation: In angiosperms, root hairs arise from the region of maturation (also known as the zone of differentiation). This zone, located proximal to the region of elongation, contains fully matured cells. 

2. In the lac operon, the z gene codes for :

a.permease

b.transacetylase

c. beta-galactosidase

d.the repressor of lac operon

Answer: c. beta-galactosidase

Explanation: In the lac operon, the z gene codes for the enzyme (beta-galactosidase) . This enzyme is essential for lactose metabolism, as it catalyzes the hydrolysis (breakdown) of lactose into its monomeric units, glucose and galactose.

• The y gene codes for permease, and the a gene codes for transacetylase.

3. Exploring molecular, genetic, and species-level diversity for products of economic importance is called:

a.Biofortification

b.Bioremediation

c.Bioprospecting

d. Biomagnification

Answer: c.Bioprospecting

Explanation:

• Biofortification is the process of increasing the nutritional value of staple food crops (such as iron, zinc, or vitamins) during plant growth through techniques like conventional breeding, genetic modification, or agronomic practices (fertilizers)

• Bioremediation is a sustainable, nature-based process that uses microorganisms (bacteria, fungi) or plants to clean up polluted environments, such as soil, water, and groundwater, by breaking down or neutralizing contaminants into non-toxic substances

• Biomagnification, also known as biological magnification or bioamplification, is the increasing concentration of toxic substances (such as heavy metals or pesticides) in the tissues of organisms at higher levels in a food chain.

4. Alpha helix is found in which level of protein structure?

a. Secondary structure

b.primary structure

c. tertiary structure

d. quaternary structure

Answer: a. Secondary structure

5. Match List I with List II :

List I	List II
A. Genetically modified organism	I. Agrobacterium tumefaciens
B. Thermostable DNA polymerase	II. Bt cotton
C. Ti plasmid	III. Thermus aquaticus
D. pBR322	IV. Escherichia coli

Choose the correct answer from the options given below :

a.A-II, B-III, C-I, D-IV

b.A-II, B-I, C-IV, D-III

c.A-I, B-IV, C-III, D-II

d. A-I, B-II, C-IV, D-III

Answer: a.A-II, B-III, C-I, D-IV

6. Match List I with List II

List I	List II
A. Productivity	I. Agrobacterium tumefaciens
B. Net Primary Productivity	II. Bt cotton
C. Gross Primary Productivity	III. Rate of biomass production
D. Secondary Productivity	IV. Escherichia coli

Choose the correct answer from the options given below:

a.A-III, B-I, C-IV, D-II

b.A-I, B-II, C-III, D-IV

c.A-I, B-III, C-IV, D-II

d. A-III, B-I, C-II, D-IV

Answer: a..A-III, B-I, C-IV, D-II

7. Since the origin and diversification of life on Earth, there have been five episodes of mass extinction of species. How is the sixth extinction, which is in progress, different from the previous episodes?

a.The present net species extinction rate is zero

b.the current species extinction rate is nearly 10 times faster than that in previous episodes

c.the present species extinction rates are 100 to 1000 times faster than in the pre-human times.

d. the current species extinction rates are far lower than those in previous episodes

Answer: c.the present species extinction rates are 100 to 1000 times faster than in the pre-human times.

Explanation:

• Correct Option (c): According to ecologists and the fossil record, the current "Sixth Extinction" is distinguished from previous mass extinctions primarily by its pace. The current rate is estimated to be 100 to 1,000 times faster than the natural "background" rates observed in pre-human times. This acceleration is largely attributed to human activities such as habitat destruction, pollution, and climate change.
• Incorrect Option (a): The species extinction rate is definitely not zero; it is significantly higher than historical averages, with nearly half of all species potentially facing extinction within the next century if current trends continue.
• Incorrect Option (b): While the extinction rate is faster, "10 times faster" is a significant underestimate compared to the 100 to 1,000 times faster rate supported by scientific data.
• Incorrect Option (d): The current rates are not lower; they are drastically higher and more rapid than the previous five episodes of mass extinction

8. Alpha-helix is found in which level of protein structure?

a. Secondary structure

b. primary structure

c. Tertiary structure

d. Quaternary structure

Answers: a. Secondary structure

Explanation: The alpha helix is found in the secondary level of protein structure. It is a common, localized, three-dimensional folding pattern where a polypeptide chain coils, stabilized by intramolecular hydrogen bonds between the carbonyl (C=O) and amino N-H)groups of the backbone

9. The main function of bulliform cells in grasses is

a. to transport water

b. to perform photosynthesis

c.to make the leaf impermeable to fungal spores

d. to minimize water loss during water stress

Answer: d. to minimize water loss during water stress

10. Identify the correct sequence of steps in each cycle of Polymerase Chain Reaction (PCR)?

a.Extension ->Annealing -> Denaturation

b. Extension ->Annealing -> Denaturation

c. Denaturation ->Annealing ->Extension

d. Denaturation -> Extension -> Annealing

Answer: c. Denaturation ->Annealing ->Extension

11. Match List I with List II

   

List I (Phase of cell cycle)	List II (Activity)
A.    G1 phase	I. Actual cell division occurs
B.    S phase	II. Cell is metabolically active and continuously grows but does not replicate its DNA
C.  G2 phase	III. Synthesis of DNA occurs and the amount of DNA per cell doubles
D. M phase	IV. Proteins are synthesized while cell growth continues

Choose the correct answer from the options given below:

a. A-IV, B-I, C-II, D-III

b. A-I, B-II, C-III, D-IV

c.A-III, B-IV, C-I, D-II

d.A-II, B-III, C-IV, D-I

Answer: d.A-II, B-III, C-IV, D-I

12. Which of the following statements are correct?

A. The Amazon rainforest being cut and cleared for cultivation of soyabeans is an example of habitat loss.

B. Steller's sea cow and passenger pigeon became extinct due to over-exploitation by humans.

C. The Nile perch introduced into Lake Victoria in East Africa helped in population growth of cichlid fish in the lake.

D. Water hyacinth is an invasive species.

E. When a species becomes extinct, the plant and animal species associated with it are not affected.

Choose the correct answer from the options given below:

1.A, B and E only

2.A, B and D only

3.C, D and E only

4.B, C and D only

.

Answer: 2.A, B and D only

13. Which of the following statements are correct with reference to a transcription unit in DNA?

A. A transcription unit in DNA is defined primarily by three regions: promoter, structural gene and terminator.

B. The promoter is said to be located towards the $5^{\prime }$-end of the structural gene.

C. The promoter is a DNA sequence that provides binding site for RNA polymerase.

D. The promoter defines the template and coding strands.

E. The terminator is located towards the $3^{\prime }$-end of the coding strand and it defines the end of the process of transcription.

Choose the correct answer from the options given below:

1.A, B, C and D only

2.A, C, D and E only

3.B,C, D and E only

4.A,B, C, D and E only

Answer: 4.A,B, C, D and E only

14.  Which one of the following statements is not true about the universal rules of binomial nomenclature?

a. Biological names are generally in Latin

b.  Both the words in a biological name, when handwritten are separately underlined or printed in italics

c. The specific epithet in the biological name starts with small letter

d. The first word in the biological name represents the specific epithet, while the second component denotes the genus. 

Answer: d. The first word in the biological name represents the specific epithet, while the second component denotes the genus. 

15. Which one of the following is the site for active ribosomal RNA synthesis?

a. Centrosome

b. Chromatin

c.KInetochore

d. Nucleolus 

16. 2(C51H98O6) +145 O2-> 102 CO2+98H2O+ENERGY

The respiratory Quotient (RQ) of a biomolecule used for respiration as per the above equation would be 

a. Between 0.5 and 0.95

b.Less than 0.5

c.1.0

d. Between 1.25 and 2

Answer: a. Between 0.5 and 0.95

Explanation

The Respiratory Quotient (RQ) of the biomolecule in the given equation is 0.7. This value is characteristic of fats (specifically tripalmitin) being used as a respiratory substrate.

1. Identify the RQ Formula

The Respiratory Quotient (RQ) is the ratio of the volume of carbon dioxide produced to the volume of oxygen consumed during respiration:
RQ= 

2. Extract Values from the Equation

From the balanced chemical equation provided:
(2(C51H98O6)+145O2->102CO2+98H2O+Energy

• CO2 produced: 102 molecules 
• O2 consumed: 145 molecules

17. Match List I with List II

List I	List II
A.    Incomplete dominance	I. Human skin colour
B.    Co-dominance	II. Inheritance of flower colour in Antirrhinum sp.
C.   Pleiotropy	III. Phenylketonuria disease in humans
D. Polygenic inheritance	IV. ABO blood groups

 

Choose the correct answer from the options given below:

a.A-II, B-IV, C-III, D-I

b. A-I, B-III, C-II, D-IV

c. A-I, B-IV, C-III, D-II

d. A-II, B-I, C-III, D-IV

Answer: a.A-II, B-IV, C-III, D-I

18. Arrange the following steps of DNA fingerprinting in a correct sequence.

A. Isolation of DNA and its digestion by restriction endonucleases.

B. Hybridisation using labelled VNTR probe.

C. Transferring of separated DNA fragments to synthetic membranes.

D. Detection of hybridised DNA fragments by autoradiography.

E. Separation of DNA fragments by electrophoresis.

Choose the correct answer from the options given below:

a.A, B, D, C, E

b.A, D,B, E, C

c.A, E, C, B, D

d.A,E,B, C, D

Answer: c) A, E, C, B, D

19. Match List I with List II

List I	List II
A. Decomposition	I. Accumulation of dark coloured amorphous colloidal substance
B. Detritus	II. Release of inorganic nutrients by the activity of microbes in soil
C. Mineralisation	III. Breaking down of complex organic matter into inorganic substances
D. Humification	IV. Dead remains of plants and animals including fecal matter

Choose the correct answer from the options given below:

1. A-IV, B-III, C-II, D-II

2.A-III, B-IV, C-II, D-I

3.A-I, B-II, C-III, D-IV

4.A-III, B-II, C-I, D-IV

Answer: 2.A-III, B-IV, C-II, D-I

20. Which of the following statements are correct with reference to packaging of DNA helix?

A. Histones are organized to form a unit of eight molecules called histone octamer.

B. Histones are negatively charged basic proteins.

C. Histones are rich in the basic amino acid residues – lysine and arginine.

D. The positively charged DNA is wrapped around the histone octamer to form nucleosome.

E. The packaging of chromatin at higher levels requires an additional set of proteins called non-histone chromosomal proteins.

Choose the correct answer from the options given below:

1. A,C and E only

2.B, D and E only

3.C, D and E only

4.A, B and D only

Answer:  1. A,C and E only

21. How many ATP and NADPH molecules are required to make one molecule of glucose through the Calvin pathway?

a. 18 ATP and 12 NADPH

b.12 ATP and 18 NADPH

c.24 ATP and 18 NADPH

d. 6 ATP and 12 NADPH

Answer: a. 18 ATP and 12 NADPH

22. The enzyme required for carboxylation in the Calvin cycle is :

a. Hexokinase

b.PEP carboxylase

c.RuBp Carboxylase oxygenase

d. Carboxypeptidase

Answer: c.RuBp Carboxylase oxygenase

23. Find the incorrect statements about photosynthesis from the following:

A. The water-splitting complex is associated with PSI

B. C4 plants use the C3 pathway of CO2 fixation as the main biosynthetic pathway

C. In C4 plants, photosynthesis does not occur

D. C3 plants exhibit Kranz anatomy

E. ATP synthesis in chloroplasts occurs through chemiosmosis

Choose the correct answer from the options given below:

a. B and C only

b. B only

c. B and E only

d. A and D only

Answer: d. A and D only

24. Arrange the following steps of somatic hybridization in a correct sequence.

A. Digestion of cell walls.

B. Isolation of naked protoplasts.

C. Fusion of protoplasts to get hybrid protoplast.

D. Isolation of single cells from two different varieties of plants.

E. Growing of hybrid protoplast to form a new plant.

Choose the correct answer from the options given below:

a) D, A, B, C, E

b) E, B, A, D, C

c) D, B, A, E, C

d) E, A, B, C, D

Answer: a.D, A, B, C, E

 25. Match List I with List II

List I	List II
A. Conjunctive tissue	I. Specialised cells in the vicinity of guard cells
B. Casparian strips	II. Endodermal cells rich in starch
C. Subsidiary cells	III. Tissue between xylem and phloem
D. Starch sheath	IV. Endodermal cells with suberin deposition

Choose the correct answer from the options given below:

a) A-IV, B-III, C-I, D-II

b)A-III, B-IV, C-II, D-I

c) A-III, B-IV, C-I, D-II

d) A-IV, B-III, C-II, D-I

Answer:

c) A-III, B-IV, C-I, D-II