NEET Biology Chapter-wise Previous Year Questions With Answers and Explanations

Biology is 360 marks out of 720 in NEET. It is the subject that decides rank, not Physics, not Chemistry.

This page has 82 chapter-wise NEET Biology PYQs from the last 7 papers, organised by chapter, with the correct answer, the trap option, and the reason the NTA designed the question that way. Not a question dump. A working revision tool.

Eight chapters. Eight sets of questions. Use the chapter you are revising today  or work through all eight in the order they appear. Every question here has appeared in an actual NEET paper. Nothing is made up or approximate.

How NEET Biology Is Structured  Chapter Distribution and Weightage

Before you start solving questions, it helps to know where each chapter sits in the paper. Not all Biology chapters are equal  and the NTA has been consistent about which ones it draws from heavily.

Biology contributes 90 questions and 360 marks, exactly 50% of the total NEET score. The paper is split between Botany and Zoology, but the split is not 50-50.

Botany vs Zoology  How Questions Are Split

Students often think of Biology as one subject. The NTA structures it as two  and your revision strategy should reflect that.

Section	Questions	Marks	Key Strength
Botany (Class 11 + 12)	40–45	160–180	Plant Physiology, Genetics, Cell Biology, Ecology
Zoology (Class 11 + 12)	45–50	180–200	Human Physiology, Reproduction, Human Health, Evolution
Total	90	360	—

Zoology contributes slightly more questions on average  and Human Physiology alone accounts for 13–15 of those. If you are short on revision time, Zoology chapters give the highest mark-per-hour return.

The 7 Chapters That Generate 60% of All Biology Questions

The NTA does not draw evenly from all 38 Biology chapters. Seven chapters have dominated NEET Biology for the last seven consecutive papers  and together they account for roughly 55–62 questions out of 90.

Chapter	Class	Avg. Questions (Last 7 NEETs)	Weightage
Genetics and Evolution	12	13–15	18–20%
Human Physiology	12	12–14	18–20%
Ecology and Environment	12	8–10	14–16%
Cell Biology and Cell Division	11	5–7	9–10%
Plant Physiology	11	6–8	10–14%
Reproduction (Flowering Plants + Human)	11+12	5–7	9–11%
Biotechnology	12	5–6	8–10%

The single most important insight from this table: Genetics and Evolution + Human Physiology together contribute 25–30 questions per paper, nearly one-third of the entire Biology section. If these two chapters are not fully revised, you are entering NEET with a 100–120 mark gap before the paper begins.

The chapters below this top 7  Animal Kingdom, Morphology, Structural Organisation  do appear, but inconsistently. Revise them after the top 7 are solid. Not before.

For a full concept-by-concept breakdown of Human Physiology  including tricks, PYQ patterns and the 8 most common mistakes  see the NEET 2026 Human Physiology guide. For Genetics and Evolution in the same depth, see the NEET 2026 Genetics and Evolution guide

The questions start in the next section  Human Physiology first, because it is where most students can gain the most marks the fastest.

Human Physiology  NEET PYQs With Answers

Human Physiology contributes 12–14 questions per paper  the highest single-chapter count in Zoology. Almost every question here comes from the same five sub-chapters: Neural Control, Chemical Coordination, Circulation, Excretion and Breathing. The NTA returns to these areas without exception.

Work through these 15 questions without looking at the answers. Then check  and for every question you got wrong, spend 5 minutes on that specific concept before moving to the next chapter.

For full concept explanations, tricks and mistake analysis for this chapter, see the NEET 2026 Human Physiology guide.

Q1. The resting membrane potential of a neuron is approximately:

(A) 0 mV (B) +70 mV (C) −70 mV (D) −90 mV

Correct: (C) −70 mV
The inside of a resting neuron is more negative than the outside  maintained by the sodium-potassium pump (3 Na⁺ out, 2 K⁺ in) and differential membrane permeability.
Trap: (A) 0 mV  “resting” does not mean neutral. The membrane is polarised even when no action potential is firing.

Q2. Which part of the human brain controls body temperature, hunger and water balance?

(A) Cerebellum (B) Medulla oblongata (C) Hypothalamus (D) Thalamus

Correct: (C) Hypothalamus
The hypothalamus regulates homeostatic functions  temperature, hunger, thirst, sleep and hormone release from the pituitary.
Trap: (B) Medulla oblongata  this controls involuntary functions like heartbeat and breathing, not temperature or hunger.

Q3. Insulin is secreted by which cells of the Islets of Langerhans?

(A) Alpha cells (B) Beta cells (C) Delta cells (D) PP cells

Correct: (B) Beta cells
Beta cells produce insulin (lowers blood glucose). Alpha cells produce glucagon (raises blood glucose). The NTA tests both  and sets one as the trap for the other.
Trap: (A) Alpha cells  students who memorise “A for Alpha, B for Beta” in alphabetical order sometimes reverse the hormones.

Q4. The pacemaker of the human heart is located in the:

(A) Left atrium (B) Right ventricle (C) Right atrium (D) AV node

Correct: (C) Right atrium
The sinoatrial (SA) node  the primary pacemaker  is located in the wall of the right atrium. It generates the electrical impulse that initiates each heartbeat.
Trap: (D) AV node  the AV node is the secondary pacemaker. It relays the impulse from atria to ventricles but does not initiate it.

Q5. In an ECG, the QRS complex represents:

(A) Atrial depolarisation (B) Ventricular depolarisation (C) Ventricular repolarisation (D) Atrial repolarisation

Correct: (B) Ventricular depolarisation
P wave = atrial depolarisation. QRS = ventricular depolarisation. T wave = ventricular repolarisation. Atrial repolarisation is masked by the QRS complex.
Trap: (C) Ventricular repolarisation  this is the T wave, not QRS. Students who know the sequence sometimes misassign the labels.

Q6. Which blood group is the universal donor for red blood cell transfusion?

(A) AB positive (B) O negative (C) O positive (D) AB negative

Correct: (B) O negative
O negative has no A, B or Rh antigens  so it cannot trigger an immune response in any recipient. O positive can only be given to Rh-positive recipients.
Trap: (C) O positive  this is the most common blood group and often confused as a universal donor. The Rh factor rules it out.

Q7. The ascending limb of the loop of Henle is:

(A) Permeable to water and impermeable to ions (B) Impermeable to water and permeable to ions (C) Permeable to both water and ions (D) Impermeable to both water and ions

Correct: (B) Impermeable to water and permeable to ions
The ascending limb actively transports ions (Na⁺, Cl⁻) out into the medullary interstitium  but water cannot follow because the wall is impermeable to it. This is what creates the concentration gradient for countercurrent multiplication.
Trap: (A)  this describes the descending limb, not the ascending. The two limbs have opposite permeability properties.

Q8. Which lung volume CANNOT be measured directly by a spirometer?

(A) Tidal volume (B) Inspiratory reserve volume (C) Expiratory reserve volume (D) Residual volume

Correct: (D) Residual volume
Residual volume (approximately 1200 mL) remains in the lungs after maximum expiration  it can never be exhaled. A spirometer measures volumes of exhaled air, so RV cannot be captured directly.
Trap: (A) Tidal volume  this is actually the easiest volume to measure with a spirometer. Students sometimes guess it because it sounds basic.

Q9. The partial pressure of CO₂ in deoxygenated blood entering the pulmonary capillaries is approximately:

(A) 40 mmHg (B) 45 mmHg (C) 104 mmHg (D) 95 mmHg

Correct: (B) 45 mmHg
Deoxygenated blood arriving at the lungs carries CO₂ at ~45 mmHg. Alveolar air has CO₂ at ~40 mmHg  so CO₂ diffuses from blood into alveoli down its partial pressure gradient.
Trap: (A) 40 mmHg  this is the alveolar CO₂ pressure, not the blood pressure. Students confuse source and destination values.

Q10. Which hormone is responsible for the “fight or flight” response?

(A) Cortisol (B) Aldosterone (C) Adrenaline (Epinephrine) (D) Thyroxine

Correct: (C) Adrenaline (Epinephrine)
Adrenaline from the adrenal medulla triggers the fight or flight response  increasing heart rate, dilating airways, redirecting blood to muscles.
Trap: (A) Cortisol  cortisol is the stress hormone involved in long-term stress response, not the acute fight or flight reaction.

Q11. ADH (Antidiuretic Hormone) acts on which part of the nephron?

(A) Proximal convoluted tubule (B) Loop of Henle (C) Distal convoluted tubule and collecting duct (D) Bowman’s capsule

Correct: (C) Distal convoluted tubule and collecting duct
ADH increases water permeability in the DCT and collecting duct  allowing more water to be reabsorbed and producing concentrated urine.
Trap: (A) PCT  water reabsorption in the PCT is obligatory and ADH-independent. ADH acts specifically on the DCT and collecting duct.

Q12. The yellow colour of urine is due to:

(A) Bilirubin (B) Urochrome (C) Urea (D) Creatinine

Correct: (B) Urochrome
Urochrome is a yellow pigment produced from the breakdown of haemoglobin  it gives urine its characteristic colour.
Trap: (A) Bilirubin  bilirubin gives urine a dark yellow-brown colour when present in abnormal amounts (jaundice). Normal urine colour is urochrome.

Q13. Which type of muscle tissue is involuntary and non-striated?

(A) Skeletal muscle (B) Cardiac muscle (C) Smooth muscle (D) Both cardiac and smooth muscle

Correct: (C) Smooth muscle
Smooth muscle is involuntary (controlled by the autonomic nervous system) and non-striated (no banding pattern). Cardiac muscle is involuntary but striated.
Trap: (D)  cardiac muscle is involuntary but it IS striated. The question specifies both involuntary AND non-striated  only smooth muscle fits both conditions.

Q14. During muscle contraction, which band does NOT change in length?

(A) I band (B) H zone (C) A band (D) Sarcomere

Correct: (C) A band
The A band represents the length of thick (myosin) filaments  and myosin filaments do not change length during contraction. I band and H zone both shorten. The sarcomere overall shortens.
Trap: (A) I band  this shorten during contraction as thin filaments slide inward. A band is the constant one.

Q15. The organ of Corti is located in the:

(A) Semicircular canals (B) Cochlea (C) Utricle (D) Saccule

Correct: (B) Cochlea
The organ of Corti sits on the basilar membrane inside the cochlea; it contains hair cells that convert sound vibrations into nerve impulses.
Trap: (A) Semicircular canals detect rotational movement and balance, not sound. The cochlea is exclusively for hearing.

Genetics and Evolution  NEET PYQs With Answers

Genetics and Evolution is the highest-weightage chapter combination in NEET Biology  13 to 15 questions per paper, accounting for 52 to 60 marks. The NTA draws from the same question types year after year: modified ratios, Chargaff’s rule calculations, pedigree analysis, theory comparisons and the human evolution sequence.

These 15 questions cover every major sub-topic. For full concept explanations and the 50-question practice set, see the NEET 2026 Genetics and Evolution guide.

Q16. In a dihybrid cross, the phenotypic ratio 9:7 indicates:

(A) Duplicate dominant epistasis (B) Complementary gene interaction (C) Dominant epistasis (D) Incomplete dominance

Correct: (B) Complementary gene interaction
Both dominant alleles (A and B) must be present together to produce one phenotype. Any other combination gives the second phenotype  ratio 9 (A_B_) : 7 (rest).
Trap: (A) Duplicate dominant epistasis  this gives 15:1, not 9:7. The ratio sum is always 16 for dihybrid crosses; the pattern identifies the interaction type.

Q17. If adenine constitutes 20% of bases in a double-stranded DNA molecule, what is the percentage of guanine?

(A) 20% (B) 30% (C) 40% (D) 10%

Correct: (B) 30%
A = T = 20% each. A + T = 40%. Remaining = G + C = 60%. Since G = C, each is 30%.
Trap: (A) 20%  students assume G = A because both are purines. Chargaff’s rule pairs A with T and G with C  not purine with purine.

Q18. Which scientist proposed the theory of use and disuse of organs?

(A) Charles Darwin (B) Hugo de Vries (C) Jean-Baptiste Lamarck (D) Thomas Malthus

Correct: (C) Jean-Baptiste Lamarck
Lamarck proposed that organs used frequently become stronger and those not used disappear over generations  and that these acquired characters are inherited.
Trap: (A) Darwin  Darwin proposed natural selection. The NTA has used this exact mismatch as a trap in multiple papers.

Q19. In pedigree analysis, two unaffected parents have an affected child. The most likely inheritance pattern is:

(A) Autosomal dominant (B) X-linked dominant (C) Autosomal recessive (D) Y-linked

Correct: (C) Autosomal recessive
Both unaffected parents must be carriers (Aa × Aa). The affected child inherits two recessive alleles (aa). This is the classic autosomal recessive pattern.
Trap: (A) Autosomal dominant  in dominant inheritance, at least one parent must be affected to pass the dominant allele.

Q20. The recombination frequency between two genes is 25%. The map distance between them is:

(A) 50 cM (B) 25 cM (C) 12.5 cM (D) 75 cM

Correct: (B) 25 cM
Recombination frequency (%) directly equals map distance in centimorgans (cM). 25% recombination = 25 cM apart.
Trap: (A) 50 cM  students sometimes double the percentage, confusing map distance calculation with other ratio-based problems.

Q21. Turner’s syndrome in humans is characterised by the karyotype:

(A) XXY (B) XYY (C) XO (D) XXX

Correct: (C) XO
Turner’s syndrome  45 chromosomes, single X (XO). Affected individuals are phenotypically female with underdeveloped ovaries. This is the only viable human monosomy.
Trap: (A) XXY  this is Klinefelter’s syndrome (male phenotype). Both involve sex chromosome abnormalities; the karyotype is the distinguishing detail.

Q22. The Miller-Urey experiment (1953) demonstrated that:

(A) Life can be created artificially in a laboratory (B) Amino acids can form spontaneously from inorganic molecules (C) DNA was the first genetic material on Earth (D) Proteins can self-replicate

Correct: (B) Amino acids can form spontaneously from inorganic molecules
Miller passed electric sparks through methane, ammonia, hydrogen and water vapour  producing amino acids. This proved organic molecules can form abiotically under early Earth conditions.
Trap: (A)  the experiment produced amino acids, not life. Life itself was never demonstrated in the Miller-Urey setup.

Q23. A carrier female for colour blindness (X^C X^c) marries a normal-visioned male (X^C Y). What is the probability that their son will be colour-blind?

(A) 25% (B) 0% (C) 100% (D) 50%

Correct: (D) 50%
Sons receive Y from father and either X^C or X^c from mother. Probability of X^c in sons = 50%.
Trap: (A) 25%  this is the probability across ALL offspring (daughters + sons). The question specifies sons only. Among sons, the probability is 50%.

Q24. Which hominid is believed to have first used fire?

(A) Australopithecus (B) Homo habilis (C) Homo erectus (D) Homo sapiens neanderthalensis

Correct: (C) Homo erectus
Homo erectus (brain volume ~900 cc) is the first hominid with evidence of fire use.
Trap: (B) Homo habilis  Homo habilis was the first to use stone tools, not fire. Students confuse the two “firsts” because both involve tool or technology use.

Q25. The Hardy-Weinberg principle states that allele frequencies in a population remain constant when:

(A) Natural selection is acting on the population (B) The population is very small (C) There is no mutation, migration, selection, genetic drift and mating is random (D) Gene flow is occurring between populations

Correct: (C)
All five conditions  no mutation, no migration, no selection, random mating and large population  must be met simultaneously for Hardy-Weinberg equilibrium.
Trap: (B) Small population  small populations experience genetic drift, which violates equilibrium. Hardy-Weinberg requires an infinitely large population.

Q26. Okazaki fragments are associated with which strand during DNA replication?

(A) Leading strand (B) Template strand (C) Lagging strand (D) Sense strand

Correct: (C) Lagging strand
The lagging strand is synthesised discontinuously  in short fragments (Okazaki fragments) that are later joined by DNA ligase.
Trap: (A) Leading strand  the leading strand is synthesised continuously toward the replication fork. Only the lagging strand produces fragments.

Q27. Which of the following is NOT a post-transcriptional modification in eukaryotes?

(A) Addition of 5′ methyl guanosine cap (B) Addition of poly-A tail (C) Splicing of introns (D) Methylation of adenine bases

Correct: (D) Methylation of adenine bases
The three main eukaryotic post-transcriptional modifications are 5′ capping, 3′ poly-A tail and splicing of introns. Adenine methylation is a prokaryotic DNA modification  not a eukaryotic RNA processing step.
Trap: (C) Splicing  this is indeed a post-transcriptional modification. Students sometimes think splicing occurs at the DNA level.

Q28. The lac operon in E. coli is induced when:

(A) Glucose is present in excess (B) Lactose is absent from the medium (C) Lactose binds to the repressor protein causing it to detach from the operator (D) The repressor binds tightly to the operator sequence

Correct: (C)
Lactose (the inducer) binds to the repressor  changing its shape so it can no longer bind the operator. RNA polymerase then transcribes the structural genes Z, Y and A.
Trap: (D)  when repressor binds the operator, transcription is switched OFF. Induction means turning the operon ON.

Q29. Analogous organs are evidence for:

(A) Divergent evolution (B) Common ancestry (C) Convergent evolution (D) Genetic drift

Correct: (C) Convergent evolution
Analogous organs (same function, different origin  like wings of insects and birds) show that unrelated organisms evolved similar structures independently in response to similar environments.
Trap: (A) Divergent evolution  this produces homologous organs (same origin, different function). Analogous = convergent. Homologous = divergent.

Q30. Down syndrome is caused by:

(A) Monosomy of chromosome 21 (B) Deletion of chromosome 21 (C) Trisomy of chromosome 21 (D) Translocation of chromosome 21 only

Correct: (C) Trisomy of chromosome 21
Down syndrome results from non-disjunction during meiosis  producing a gamete with two copies of chromosome 21. The resulting zygote has 47 chromosomes.
Trap: (A) Monosomy  monosomy of chromosome 21 is lethal. Students confuse this with Turner’s syndrome (XO monosomy), which is the only viable human monosomy.

Cell Biology and Biomolecules  NEET PYQs With Answers

Cell Biology draws from two classes  Class 11 Cell Structure and Class 12 Biomolecules  and contributes 5 to 7 questions per paper. The NTA focuses heavily on cell organelle functions, cell division stages and enzyme properties. These are mostly direct NCERT fact questions; high accuracy is achievable here with focused revision.

Q31. Which cell organelle is known as the “powerhouse of the cell”?

(A) Ribosome (B) Golgi apparatus (C) Mitochondria (D) Endoplasmic reticulum

Correct: (C) Mitochondria
Mitochondria produce ATP through cellular respiration  hence the “powerhouse” description. They have a double membrane and their own circular DNA.
Trap: (A) Ribosome  ribosomes synthesise proteins, not ATP. This question appears in NEET as a statement question more than a direct definition question.

Q32. The fluid mosaic model of the plasma membrane was proposed by:

(A) Robert Hooke (B) Singer and Nicolson (C) Watson and Crick (D) Schleiden and Schwann

Correct: (B) Singer and Nicolson
Singer and Nicolson proposed the fluid mosaic model in 1972  describing the membrane as a fluid phospholipid bilayer with proteins embedded in it.
Trap: (D) Schleiden and Schwann  they proposed the cell theory, not the fluid mosaic model. Both involve foundational biology concepts which is why students mix them.

Q33. During which phase of mitosis do chromosomes align at the equatorial plate?

(A) Prophase (B) Anaphase (C) Metaphase (D) Telophase

Correct: (C) Metaphase
In metaphase, chromosomes reach maximum condensation and align at the metaphase plate (cell equator)  attached to spindle fibres at their centromeres.
Trap: (A) Prophase  chromosomes condense in prophase but do not align at the equator. Alignment is specifically metaphase.

Q34. Which of the following is NOT a function of the smooth endoplasmic reticulum (SER)?

(A) Lipid synthesis (B) Detoxification of drugs (C) Protein synthesis (D) Steroid hormone synthesis

Correct: (C) Protein synthesis
Protein synthesis occurs on ribosomes  either free in the cytoplasm or attached to the rough ER (RER). The SER has no ribosomes and is involved in lipid synthesis, steroid synthesis and detoxification.
Trap: (D) Steroid hormone synthesis  this IS a function of SER, so it should not be chosen. Students sometimes select it because steroids feel like an unusual SER function.

Q35. The enzyme responsible for the transcription of DNA to RNA is:

(A) DNA polymerase (B) RNA polymerase (C) Reverse transcriptase (D) Ligase

Correct: (B) RNA polymerase
RNA polymerase reads the DNA template strand and synthesises a complementary RNA strand (mRNA) in the 5′ to 3′ direction.
Trap: (C) Reverse transcriptase  this enzyme transcribes RNA back to DNA (found in retroviruses). The question asks about the standard DNA to RNA direction.

Q36. Km value of an enzyme represents:

(A) Maximum velocity of the reaction (B) Substrate concentration at which reaction velocity is half of Vmax (C) Total enzyme concentration (D) Optimum pH for enzyme activity

Correct: (B) Substrate concentration at half-Vmax
The Michaelis constant (Km) measures enzyme-substrate affinity. A low Km means high affinity  the enzyme reaches half-maximal velocity at a low substrate concentration.
Trap: (A) Vmax  this is maximum velocity, a different parameter. Students confuse Km and Vmax because both come from the same Michaelis-Menten equation.

Q37. Centrioles are absent in which of the following cells?

(A) Animal cells (B) Higher plant cells (C) Fungal cells (D) Algal cells

Correct: (B) Higher plant cells
Higher plant cells lack centrioles  they form spindle fibres during cell division using spindle pole bodies instead. Animal cells contain centrioles as part of the centrosome.
Trap: (A) Animal cells  animal cells have centrioles. Higher plant cells are the classic example of cells that form spindles without centrioles.

Q38. Which of the following bonds maintains the secondary structure of proteins?

(A) Peptide bonds (B) Disulphide bonds (C) Hydrogen bonds (D) Ionic bonds

Correct: (C) Hydrogen bonds
The alpha-helix and beta-pleated sheet (secondary structures) are maintained by hydrogen bonds between the CO and NH groups of the polypeptide backbone.
Trap: (A) Peptide bonds  these hold amino acids together in the primary structure (sequence), not the secondary structure (shape).

Q39. G1, S and G2 phases collectively constitute:

(A) M phase (B) Interphase (C) Prophase (D) Cytokinesis

Correct: (B) Interphase
Interphase is the preparatory phase of the cell cycle  G1 (growth), S (DNA synthesis) and G2 (preparation for division) together make up interphase before M phase begins.
Trap: (A) M phase  M phase is mitosis itself (prophase, metaphase, anaphase, telophase). Interphase precedes M phase.

Q40. Which of the following is non-reducing sugar?

(A) Glucose (B) Fructose (C) Maltose (D) Sucrose

Correct: (D) Sucrose
Sucrose is a non-reducing sugar because both anomeric carbons of glucose and fructose are involved in the glycosidic bond  leaving no free aldehyde or ketone group to act as a reducing agent.
Trap: (C) Maltose  maltose IS a reducing sugar because one anomeric carbon remains free. Only sucrose among common disaccharides is non-reducing.

Plant Physiology  NEET PYQs With Answers

Plant Physiology contributes 6 to 8 questions per paper  consistently across all seven years. The NTA draws from three main areas: Photosynthesis (light reactions vs dark reactions, C3 vs C4), Respiration (glycolysis, Krebs cycle, ATP yield) and Plant Growth Regulators (hormones and their specific functions).

The most common student mistake here: studying the process narrative from NCERT without drilling the specific facts the NTA tests  pigment absorption wavelengths, ATP counts, which hormone does what. These questions reward precision, not general understanding.

Q41. The primary acceptor of CO₂ during the Calvin cycle (C3 pathway) is:

(A) Ribulose bisphosphate (RuBP) (B) Phosphoglycerate (PGA) (C) Oxaloacetate (OAA) (D) Phosphoenolpyruvate (PEP)

Correct: (A) Ribulose bisphosphate (RuBP)
CO₂ combines with RuBP (a 5-carbon compound) in the presence of RuBisCO enzyme  producing two 3-carbon PGA molecules. This is the first step of the Calvin cycle.
Trap: (C) Oxaloacetate  OAA is the primary CO₂ acceptor in C4 plants (Hatch-Slack pathway), not C3. The NTA specifically tests the distinction between C3 and C4 primary acceptors.

Q42. Which photosynthetic pigment absorbs light in the red and blue-violet regions of the spectrum?

(A) Xanthophyll (B) Carotenoids (C) Chlorophyll a (D) Phycoerythrin

Correct: (C) Chlorophyll a
Chlorophyll a is the primary photosynthetic pigment  it absorbs maximally at 430 nm (blue-violet) and 680 nm (red). It is the only pigment that directly participates in the light reaction.
Trap: (B) Carotenoids  carotenoids are accessory pigments that absorb blue-violet light but transfer energy to chlorophyll a. They do not directly drive the light reaction.

Q43. The net gain of ATP molecules from the complete oxidation of one glucose molecule through aerobic respiration is:

(A) 2 ATP (B) 8 ATP (C) 38 ATP (D) 36–38 ATP

Correct: (D) 36–38 ATP
The accepted range in NCERT is 36–38 ATP per glucose molecule  depending on the shuttle mechanism used to transfer NADH from glycolysis into the mitochondria.
Trap: (C) 38 ATP  this was the older textbook value. NCERT now states 36–38 as the range. The NTA tests the range, not the exact number.

Q44. Glycolysis occurs in which part of the cell?

(A) Mitochondrial matrix (B) Inner mitochondrial membrane (C) Cytoplasm (D) Nucleus

Correct: (C) Cytoplasm
Glycolysis is the first stage of cellular respiration  it breaks glucose into two pyruvate molecules in the cytoplasm, producing 2 ATP and 2 NADH. It does not require oxygen.
Trap: (A) Mitochondrial matrix  the Krebs cycle occurs in the mitochondrial matrix. Glycolysis precedes the Krebs cycle and happens entirely in the cytoplasm.

Q45. Which plant hormone is responsible for apical dominance?

(A) Gibberellin (B) Cytokinin (C) Auxin (D) Abscisic acid

Correct: (C) Auxin
Auxin (IAA) produced at the shoot apex suppresses the growth of lateral buds  a phenomenon called apical dominance. Removing the apex (decapitation) releases lateral bud growth.
Trap: (B) Cytokinin  cytokinin actually promotes lateral bud growth and counters apical dominance. It is the antagonist of auxin in this context, not the cause.

Q46. The C4 pathway (Hatch-Slack pathway) takes place in which cells?

(A) Guard cells and epidermal cells (B) Mesophyll cells and bundle sheath cells (C) Palisade cells only (D) Spongy mesophyll cells only

Correct: (B) Mesophyll cells and bundle sheath cells
In C4 plants, CO₂ is first fixed in mesophyll cells (producing OAA → malate) and then released in bundle sheath cells where the Calvin cycle occurs. This spatial separation prevents photorespiration.
Trap: (C) Palisade cells only  this describes C3 photosynthesis anatomy. The defining feature of C4 plants is the two-cell system  mesophyll + bundle sheath.

Q47. Abscisic acid (ABA) is known as:

(A) Stress hormone (B) Growth hormone (C) Fruit ripening hormone (D) Cell division hormone

Correct: (A) Stress hormone
ABA accumulates during drought, cold and other stress conditions  triggering stomatal closure to reduce water loss. It also promotes seed dormancy.
Trap: (C) Fruit ripening hormone  ethylene is the fruit ripening hormone. ABA and ethylene are both associated with “ending” processes (dormancy/ripening) which is why students confuse them.

Q48. Which of the following is a long-day plant?

(A) Tobacco (B) Soybean (C) Wheat (D) Chrysanthemum

Correct: (C) Wheat
Wheat flowers when the day length exceeds its critical photoperiod  making it a long-day plant. It requires exposure to long days (short nights) for flowering induction.
Trap: (A) Tobacco  tobacco (Maryland Mammoth variety) is a short-day plant. Students associate tobacco with a common NCERT example and default to it without checking the photoperiod type.

Q49. The Kranz anatomy is characteristic of which type of plants?

(A) C3 plants (B) CAM plants (C) C4 plants (D) Hydrophytes

Correct: (C) C4 plants
Kranz anatomy refers to the ring of bundle sheath cells surrounding vascular bundles in C4 plants  visible as a distinct “wreath” structure in cross-sections.
Trap: (B) CAM plants  CAM plants fix CO₂ at night (temporal separation) but do not have Kranz anatomy. Kranz anatomy = spatial separation = C4 only.

Q50. Photorespiration results in:

(A) Net gain of ATP and NADPH (B) No net gain of sugar and wasteful consumption of ATP (C) Production of glucose from CO₂ (D) Increased efficiency of photosynthesis

Correct: (B) No net gain of sugar and wasteful consumption of ATP
Photorespiration occurs when RuBisCO acts on O₂ instead of CO₂  producing no useful sugar and consuming ATP. It reduces the efficiency of photosynthesis  hence C4 plants evolved the Kranz anatomy to suppress it.
Trap: (D) Increased efficiency  photorespiration is the opposite of efficient. It is called the “wasteful” pathway specifically because it consumes ATP without producing useful carbon compounds.

Reproduction  NEET PYQs With Answers

Reproduction contributes 5 to 7 questions per paper  split between Flowering Plant Reproduction (Botany) and Human Reproduction (Zoology). The NTA tests both sub-chapters with equal frequency, so neither can be skipped. Flowering plants questions focus on pollination, fertilisation and seed development. Human reproduction questions focus on the menstrual cycle, fertilisation, embryonic development and reproductive health.

Q51. Double fertilisation in angiosperms involves:

(A) Fusion of two male gametes with the egg cell (B) Fusion of one male gamete with egg and another with two polar nuclei (C) Fusion of two female gametes (D) Fusion of pollen tube with style

Correct: (B)
One male gamete (n) fuses with the egg (n) → zygote (2n). The second male gamete (n) fuses with the two polar nuclei (n+n) → primary endosperm nucleus (3n). This is double fertilisation.
Trap: (A)  two male gametes do not both fuse with the egg. One goes to the egg, one goes to the polar nuclei. The NTA tests the destination of each gamete.

Q52. The endosperm in angiosperms is:

(A) Diploid (2n) (B) Haploid (n) (C) Triploid (3n) (D) Tetraploid (4n)

Correct: (C) Triploid (3n)
The primary endosperm nucleus (n + n + n = 3n) develops into the endosperm  triploid tissue that nourishes the developing embryo.
Trap: (A) Diploid  the zygote is diploid, not the endosperm. Students confuse the two products of double fertilisation.

Q53. Pollen grains can be stored for long periods in:

(A) Liquid nitrogen (−196°C) (B) Normal room temperature (C) Distilled water at 4°C (D) Saline solution at 37°C

Correct: (A) Liquid nitrogen (−196°C)
Pollen storage in liquid nitrogen (cryopreservation) allows long-term viability  used extensively in crop breeding programmes and pollen banks.
Trap: (C) 4°C  refrigeration can preserve pollen short-term but not long-term. The NTA specifically tests “long periods”  which points to liquid nitrogen cryopreservation.

Q54. The corpus luteum in the human female produces:

(A) Oestrogen only (B) FSH and LH (C) Progesterone and oestrogen (D) Testosterone

Correct: (C) Progesterone and oestrogen
After ovulation, the ruptured Graafian follicle transforms into the corpus luteum  which secretes progesterone (primarily) and oestrogen to maintain the uterine lining for potential implantation.
Trap: (B) FSH and LH  these are anterior pituitary hormones that regulate the ovarian cycle. The corpus luteum itself produces steroid hormones, not gonadotropins.

Q55. Ovulation in the human menstrual cycle is triggered by a surge in:

(A) FSH (B) LH (C) Progesterone (D) Oestradiol

Correct: (B) LH
A sharp LH surge (LH peak) around Day 14 of the menstrual cycle triggers rupture of the mature Graafian follicle and release of the secondary oocyte  ovulation.
Trap: (A) FSH  FSH stimulates follicle development but does not trigger ovulation. The LH surge is the specific trigger.

Q56. Capacitation refers to:

(A) Formation of acrosome in sperm (B) Maturation process of sperm in female reproductive tract (C) Development of egg after fertilisation (D) Implantation of blastocyst

Correct: (B) Maturation process of sperm in female reproductive tract
Capacitation is the process by which sperm undergo final maturation in the female reproductive tract  becoming fully capable of fertilising an egg. It involves changes in the sperm membrane and motility.
Trap: (A) Acrosome formation  the acrosome forms during spermatogenesis in the testis, not during capacitation. Capacitation is a post-ejaculation process.

Q57. The morula stage in human embryonic development consists of:

(A) 8–16 blastomeres  solid ball of cells (B) A hollow ball of cells with a blastocoel (C) A bilaminar disc (D) A gastrula with three germ layers

Correct: (A) 8–16 blastomeres  solid ball of cells
After fertilisation, the zygote undergoes cleavage  successive divisions producing a solid ball of cells (morula). The morula then develops a fluid-filled cavity to become the blastocyst.
Trap: (B) Hollow ball with blastocoel  this describes the blastocyst stage, not the morula. Morula → blastocyst is a frequently tested developmental sequence.

Q58. Which contraceptive method has the highest efficacy?

(A) Condoms (B) Oral contraceptive pills (C) Copper-T (IUCD) (D) Diaphragm

Correct: (C) Copper-T (IUCD)
Intrauterine devices (IUDs) including Copper-T have the highest contraceptive efficacy among reversible methods  over 99% when correctly inserted. They work by preventing sperm motility and fertilisation.
Trap: (B) Oral contraceptive pills  pills are highly effective when taken correctly but have a higher typical-use failure rate than IUDs due to user error.

Q59. Spermatogenesis in humans occurs in the:

(A) Epididymis (B) Seminal vesicle (C) Seminiferous tubules (D) Prostate gland

Correct: (C) Seminiferous tubules
Sperm cells are produced in the seminiferous tubules of the testes  through a sequence of mitotic and meiotic divisions (spermatogonia → spermatocytes → spermatids → spermatozoa).
Trap: (A) Epididymis  the epididymis is where sperm mature and are stored, not where they are produced. Students confuse production (seminiferous tubules) with maturation (epididymis).

Q60. Which of the following is the correct sequence of embryonic germ layers from outer to inner?

(A) Mesoderm → Ectoderm → Endoderm (B) Ectoderm → Mesoderm → Endoderm (C) Endoderm → Mesoderm → Ectoderm (D) Ectoderm → Endoderm → Mesoderm

Correct: (B) Ectoderm → Mesoderm → Endoderm
Gastrulation produces three germ layers: ectoderm (outermost  skin, nervous system), mesoderm (middle  muscles, skeleton, circulatory system) and endoderm (innermost  gut, lungs, liver).
Trap: (A)  reversing ectoderm and mesoderm. “Ecto” = outer, “meso” = middle, “endo” = inner  the prefixes give the correct order.

Ecology  NEET PYQs With Answers

Ecology contributes 8 to 10 questions per paper  the third highest chapter block in Biology. The NTA draws primarily from Organisms and Populations (population interactions, growth curves), Ecosystem (energy flow, food chains, nutrient cycles) and Biodiversity and Conservation (hotspots, extinction, in-situ vs ex-situ). These questions are almost entirely direct NCERT fact recall  making this one of the highest-accuracy chapters with focused revision.

Q61. Which of the following represents a commensal relationship?

(A) Lichens (algae and fungi) (B) Orchid growing on a tree branch (C) Roundworm in the human intestine (D) Clownfish and sea anemone

Correct: (B) Orchid growing on a tree branch
Commensalism  one organism benefits (+), the other is neither harmed nor helped (0). The orchid uses the tree for support and benefits; the tree is unaffected.
Trap: (A) Lichens  lichens are a classic mutualism (+/+), not commensalism. Both algae (photosynthesis) and fungi (protection, water absorption) benefit.

Q62. The logistic growth curve (S-shaped curve) of a population is described by the equation:

(A) dN/dt = rN (B) dN/dt = rN (K−N)/K (C) N = N₀ × e^rt (D) dN/dt = K − N

Correct: (B) dN/dt = rN (K−N)/K
The logistic growth equation incorporates carrying capacity (K)  growth slows as the population approaches K. The term (K−N)/K represents the fraction of resources still available.
Trap: (A) dN/dt = rN  this is the exponential growth equation (J-shaped curve), with no carrying capacity limit. The NTA tests both equations and their associated curve shapes.

Q63. The 10% law of energy transfer in an ecosystem was given by:

(A) Odum (B) Lindeman (C) Tansley (D) Haeckel

Correct: (B) Lindeman
Raymond Lindeman proposed the 10% law  only about 10% of energy is transferred from one trophic level to the next. The remaining 90% is lost as heat through metabolic processes.
Trap: (A) Odum  Odum made significant contributions to ecosystem ecology but did not propose the 10% law. Lindeman is the specific name the NTA tests for this law.

Q64. Which of the following is an example of ex-situ conservation?

(A) Biosphere reserve (B) National park (C) Cryopreservation of seeds in a gene bank (D) Wildlife sanctuary

Correct: (C) Cryopreservation of seeds in a gene bank
Ex-situ conservation means preserving organisms outside their natural habitat  gene banks, seed banks, zoological parks, botanical gardens and cryopreservation are all ex-situ methods.
Trap: (A) Biosphere reserve  this is in-situ conservation (protection within the natural habitat). National parks and wildlife sanctuaries are also in-situ.

Q65. The biodiversity hotspot concept was proposed by:

(A) E.O. Wilson (B) Norman Myers (C) Robert May (D) Paul Ehrlich

Correct: (B) Norman Myers
Norman Myers identified and defined biodiversity hotspots in 1988  regions with exceptionally high species richness and endemism that face severe habitat loss.
Trap: (A) E.O. Wilson  Wilson made major contributions to biodiversity science and coined “biodiversity” but did not propose the hotspot concept. Myers is the specific attribution.

Q66. Pyramid of energy in an ecosystem is always:

(A) Inverted (B) Upright (C) Spindle-shaped (D) Can be inverted or upright depending on the ecosystem

Correct: (B) Upright
The pyramid of energy is always upright  energy is always lost at each trophic level and can never increase moving up the pyramid. This is unlike pyramids of numbers and biomass which can be inverted.
Trap: (D)  students apply the flexibility of number/biomass pyramids to energy pyramids. Energy pyramids have no exceptions  always upright, always decreasing.

Q67. Which of the following is the correct sequence of a carbon cycle pathway?

(A) Atmosphere → Producers → Consumers → Decomposers → Atmosphere (B) Producers → Atmosphere → Consumers → Decomposers (C) Decomposers → Consumers → Producers → Atmosphere (D) Consumers → Atmosphere → Producers → Consumers

Correct: (A)
Carbon moves from the atmosphere (CO₂) into producers through photosynthesis, then to consumers through feeding, then to decomposers through death and decay, and finally returns to the atmosphere through respiration and decomposition.
Trap: (B)  carbon enters producers from the atmosphere, not the other way around. Students sometimes reverse the direction of atmospheric exchange.

Q68. The term “ecosystem” was coined by:

(A) Odum (B) Tansley (C) Haeckel (D) Warming

Correct: (B) Tansley
A.G. Tansley coined the term “ecosystem” in 1935  describing the interaction between living organisms and their physical environment as a functional unit.
Trap: (C) Haeckel  Haeckel coined the term “ecology” in 1869. Students confuse “ecology” (Haeckel) with “ecosystem” (Tansley)  both are one-person attributions that the NTA tests together.

Biotechnology  NEET PYQs With Answers

Biotechnology contributes 5 to 6 questions per paper  drawn almost entirely from two chapters: Biotechnology Principles and Processes (PCR, rDNA, gel electrophoresis) and Biotechnology and its Applications (Bt cotton, golden rice, ELISA, gene therapy). These chapters have narrow but predictable question types. Students who know the named techniques and the specific organisms/applications used in each score consistently here.

Q69. PCR (Polymerase Chain Reaction) is used to:

(A) Sequence proteins (B) Amplify a specific DNA fragment in vitro (C) Translate mRNA into protein (D) Separate DNA fragments by size

Correct: (B) Amplify a specific DNA fragment in vitro
PCR uses repeated cycles of denaturation, annealing and extension to amplify a target DNA sequence exponentially  producing millions of copies from a small initial sample.
Trap: (D) Separate DNA by size  this describes gel electrophoresis, not PCR. Both are core Biotechnology techniques that the NTA keeps as adjacent trap options.

Q70. Restriction endonucleases cut DNA at specific sequences called:

(A) Promoter sequences (B) Palindromic sequences (C) Terminator sequences (D) Operator sequences

Correct: (B) Palindromic sequences
Restriction enzymes recognise and cut specific palindromic sequences  sequences that read the same on both strands in the 5’→3′ direction. Example: EcoRI recognises GAATTC/CTTAAG.
Trap: (A) Promoter sequences  promoters are DNA regions where RNA polymerase binds for transcription. Restriction enzymes cut at palindromic recognition sites, not promoters.

Q71. But toxin in Bacillus thuringiensis is encoded by which gene?

(A) nif gene (B) cry gene (C) bar gene (D) gus gene

Correct: (B) cry gene
The cry (crystal) genes in Bacillus thuringiensis encode the Cry proteins  insecticidal crystal proteins (Bt toxin) that are toxic to specific insect larvae. Bt cotton contains the cry1Ac and cry2Ab genes.
Trap: (A) nif gene  nif genes are nitrogen fixation genes in bacteria like Rhizobium. Unrelated to Bt toxin.

Q72. ELISA (Enzyme-Linked Immunosorbent Assay) is primarily used to detect:

(A) DNA sequences (B) Antigens or antibodies in a sample (C) Chromosome abnormalities (D) Enzyme activity in blood

Correct: (B) Antigens or antibodies
ELISA uses enzyme-labelled antibodies to detect the presence and quantity of specific antigens (or antibodies) in a sample  commonly used to diagnose HIV, hepatitis and other infectious diseases.
Trap: (A) DNA sequences  DNA detection is done by PCR or Southern blotting. ELISA is a protein/antibody detection technique, not a nucleic acid technique.

Q73. Golden rice was developed to address deficiency of:

(A) Iron (B) Vitamin C (C) Vitamin A (D) Zinc

Correct: (C) Vitamin A
Golden rice was genetically engineered to produce beta-carotene (a Vitamin A precursor)  addressing Vitamin A deficiency in populations where rice is the dietary staple. The yellow colour comes from beta-carotene.
Trap: (A) Iron  iron-enriched biofortified crops exist (e.g., IRRI rice varieties) but golden rice specifically addresses Vitamin A deficiency, not iron.

Q74. Agrobacterium tumefaciens is used in plant genetic engineering because:

(A) It is a nitrogen-fixing bacterium (B) Its Ti plasmid can transfer DNA into plant cells (C) It produces restriction enzymes (D) It synthesises plant hormones naturally

Correct: (B) Ti plasmid transfers DNA into plant cells
Agrobacterium tumefaciens carries the Ti (tumour-inducing) plasmid  which has the natural ability to integrate a segment (T-DNA) into the plant genome. Scientists exploit this mechanism to introduce desired genes into plants.
Trap: (D) Synthesises plant hormones  the wild-type Ti plasmid does cause hormone production (hence tumour formation), but this is not why it is used as a vector. Its DNA transfer ability is the relevant property.

Q75. Gel electrophoresis separates DNA fragments based on:

(A) Base composition (GC vs AT content) (B) Their size  smaller fragments move farther (C) Their charge only (D) Temperature of denaturation

Correct: (B) Size  smaller fragments move farther
In agarose gel electrophoresis, DNA fragments migrate toward the positive electrode. Smaller fragments move faster and farther through the gel matrix. Fragment size is determined by comparing to a DNA ladder.
Trap: (A) Base composition  all DNA fragments carry the same charge per base pair (negative due to phosphate groups). Separation is purely by size, not sequence or base composition.

Q76. Cry1Ac protein from Bacillus thuringiensis is effective against:

(A) Fungal pathogens (B) Cotton bollworms (C) Nematodes (D) Viral diseases

Correct: (B) Cotton bollworms
Cry1Ac is specifically effective against lepidopteran insects  including cotton bollworm (Helicoverpa armigera). But cotton carrying the cry1Ac gene is resistant to this pest.
Trap: (C) Nematodes  nematode resistance in plants uses different technology (RNA interference/RNAi). Cry proteins target insect larvae, not nematodes.

Human Health and Disease  NEET PYQs With Answers

Human Health and Disease contributes 5 to 6 questions per paper  and recent papers have shown an upward trend in this chapter’s representation. The NTA tests four main areas: innate vs adaptive immunity, specific diseases (AIDS, cancer, malaria), drugs and addiction, and the role of antibodies. These are highly factual questions  most answered correctly with direct NCERT recall.

Q77. Which cells are primarily attacked by the HIV virus?

(A) B lymphocytes (B) Red blood cells (C) Helper T lymphocytes (TH cells) (D) Macrophages only

Correct: (C) Helper T lymphocytes (TH cells)
HIV specifically targets and destroys CD4+ helper T cells  progressively weakening cell-mediated immunity. As TH cell count falls below 200 cells/μL, the patient is classified as having AIDS.
Trap: (D) Macrophages only  HIV does infect macrophages (and uses them as initial replication sites) but the primary target and the basis of AIDS progression is the destruction of TH cells.

Q78. Which type of immunity involves memory cells that provide faster response upon second exposure?

(A) Innate immunity (B) Active immunity (C) Passive immunity (D) Non-specific immunity

Correct: (B) Active immunity
Active immunity develops when the body produces its own antibodies and memory cells  either through infection or vaccination. Memory cells enable a rapid secondary immune response upon re-exposure.
Trap: (C) Passive immunity  passive immunity involves transfer of ready-made antibodies (e.g., mother to infant through colostrum). No memory cells are formed; the protection is temporary.

Q79. The drug heroin is chemically derived from:

(A) Cannabis sativa (B) Papaver somniferum (C) Atropa belladonna (D) Erythroxylum coca

Correct: (B) Papaver somniferum
Heroin (diacetylmorphine) is derived from morphine  which is extracted from the latex of Papaver somniferum (opium poppy). It acts on opioid receptors in the brain.
Trap: (A) Cannabis sativa produces cannabinoids (THC), not heroin. The NTA frequently tests plant source → drug type associations as a single statement.

Q80. Malaria is caused by:

(A) Wuchereria bancrofti (B) Plasmodium vivax (C) Leishmania donovani (D) Trypanosoma brucei

Correct: (B) Plasmodium vivax
Malaria in humans is caused by four Plasmodium species  P. vivax (most common), P. falciparum (most dangerous), P. malariae and P. ovale. All are transmitted by the female Anopheles mosquito.
Trap: (A) Wuchereria bancrofti  this causes filariasis (elephantiasis), not malaria. Both are mosquito-transmitted parasitic diseases, which is why they appear as trap options for each other.

Q81. Cancer cells are characterised by:

(A) Contact inhibition and normal cell division (B) Loss of contact inhibition and uncontrolled cell division (C) Controlled cell division and metastasis (D) Apoptosis and programmed cell death

Correct: (B) Loss of contact inhibition and uncontrolled cell division
Normal cells stop dividing when they come into contact with other cells (contact inhibition). Cancer cells lose this property  dividing continuously and invasively, and potentially spreading to other tissues (metastasis).
Trap: (A) Contact inhibition and normal division  this describes normal cells, not cancer cells. The question asks about cancer specifically.

Q82. The protein coat of a virus is called:

(A) Capsomere (B) Capsid (C) Envelope (D) Prion

Correct: (B) Capsid
The capsid is the protein coat that surrounds and protects the viral genetic material. It is made of individual protein subunits called capsomeres.
Trap: (A) Capsomere  capsomeres are the individual protein units that make up the capsid. The capsid is the entire protein coat  students confuse the part (capsomere) with the whole (capsid).

How NTA Frames Biology Questions  Patterns Across All Chapters

Knowing the content is necessary. Knowing how the NTA packages that content into questions is what separates a student who scores 280 in Biology from one who scores 340.

The NTA uses the same question formats year after year  and each format has a specific reading strategy. Students who recognise the format before they read the question solve it faster and more accurately than those who treat every question the same way.

Three question types dominate NEET Biology and appear across all eight chapters covered in this blog.

Assertion-Reason Questions  How to Approach Them

Assertion-Reason questions give two statements  an Assertion (A) and a Reason (R)  and ask you to evaluate whether each is true and whether R correctly explains A.

The four answer options are always:

• (A) Both A and R are true and R is the correct explanation of A
• (B) Both A and R are true but R is NOT the correct explanation of A
• (C) A is true but R is false
• (D) A is false but R is true

The most common NTA trap in this format: Both statements are individually true  but R does not actually explain A. Students who confirm both statements are true immediately select option (A) without checking the logical link between them.

The correct approach: First confirm whether each statement is independently true. Then  and only then  ask: does R mechanistically cause or explain A? If the statements are causally unrelated, the answer is (B) not (A).

Example from NEET: Assertion: Smooth ER is involved in detoxification. Reason: Smooth ER has ribosomes that produce detoxification enzymes. Both A and R appear plausible  but R is false (SER has no ribosomes). Answer: (C).

Match the Column and Multi-Statement Questions

Match the Column questions pair items from two lists  and the NTA routinely places one correct-looking wrong pair to disrupt students who eliminate options.

Strategy: Work from the pair you are most certain about. Use it to eliminate answer options  then work toward the uncertain pairs. Never try to match all four pairs simultaneously.

Multi-statement questions (Type: “Which of the following statements is/are correct?”) are where NCERT line-by-line reading pays off most. 

The NTA lifts exact lines and adds subtle errors: a wrong enzyme name, an inverted relationship, a species attribution switched between two organisms. Students who have read NCERT closely catch these. Students who revised from notes or summaries miss them.

Diagram-Based Questions  Which Diagrams Generate Questions

The NTA draws diagram-based questions from the same set of Biology diagrams year after year. These are not random, they are predictable. The ten diagrams that have appeared most consistently across NEET papers from 2015–2025 are:

Diagram	Chapter	What the NTA tests
TS of seminiferous tubule	Human Reproduction	Cell stage identification
Neuron structure	Neural Control	Part labelling + function
Cardiac cycle / ECG waves	Circulation	Wave identification + meaning
Nephron structure	Excretion	Segment function (ADH, loop)
Calvin cycle / C4 pathway	Photosynthesis	Compound at each step
Lac operon	Molecular Biology	ON/OFF state identification
Pedigree chart	Genetics	Inheritance pattern
Gel electrophoresis bands	Biotechnology	Fragment size interpretation
Food web / Pyramid	Ecology	Trophic level + rule application
Embryonic development stages	Reproduction	Stage name + cell count

Revision tip: For each diagram above, practise labelling it from memory  not from reference. If you cannot label it without looking, you cannot answer the question under exam pressure.

Frequently Asked Questions  NEET Biology PYQs

Which Biology chapter has the most questions in NEET 2026?

Genetics and Evolution consistently contributes the most questions  13 to 15 per paper, accounting for roughly 18–25% of the Biology section. Human Physiology is the second highest at 12–14 questions. Together these two chapters generate nearly one-third of all Biology marks  making them the highest-priority revision chapters regardless of your current score level.

Is solving NEET Biology PYQs from the last 10 years enough for NEET 2026?

Solving the last 10 years of chapter-wise PYQs is the single most efficient Biology preparation strategy  but it is not complete on its own. Approximately 10% of NEET questions in recent papers are exact concept repeats from the previous five years. The remaining 90% are new questions built on the same concepts. PYQs teach you what the NTA tests and how it frames questions  NCERT revision teaches you the concepts that answer those questions. Both are necessary. Neither works optimally without the other.

How many Biology questions come from Class 11 vs Class 12?

Class 12 Biology contributes approximately 55% of NEET Biology questions  and Class 11 contributes 45%. In practical terms: Genetics and Evolution (Class 12), Human Physiology (Class 12  though foundations are Class 11) and Biotechnology (Class 12) are the dominant Class 12 chapters. Cell Biology, Plant Physiology and Diversity chapters draw from both classes. Students who deprioritise Class 11 entirely risk losing 40+ Biology marks.

Is NCERT enough for NEET Biology 2026?

For Biology, yes, NCERT is enough, provided you read it line by line and not just chapter by chapter. The NTA lifts questions directly from NCERT text, diagrams, tables and exercises. Questions answered incorrectly in Biology are almost always traced back to a specific NCERT line that was paraphrased in revision rather than read exactly. No supplementary book, coaching module or notes package replaces NCERT Biology for NEET. Additional resources are useful only for practice questions  not for content.

How to use Biology PYQs effectively in the last 30 days?

Use PYQs chapter-wise in Weeks 1 and 2  not as full-length papers. Attempt a chapter-wise PYQ set immediately after revising that chapter  while the concepts are fresh. This tells you exactly which parts of the chapter you understood correctly and which you only thought you understood. In Weeks 3 and 4, switch to full-length mocks that include Biology as part of the complete 90-question section  to build the stamina and time management that chapter-wise practice alone cannot replicate. After any mock, spend at least 20 minutes specifically on Biology wrong answers before moving to Physics and Chemistry analysis.

Conclusion

These 82 questions cover the chapters that generate roughly 80% of your Biology marks in NEET 2026. Work through them chapter by chapter  not in one sitting. The pattern is clear: the NTA tests the same concepts, from the same NCERT sections, using the same trap options. Once you can recognise the trap in a question type, you are not just answering that question correctly  you are answering every future variation of it correctly too.

If you find that mock test analysis, identifying which specific concepts to fix, or staying consistent in the final weeks are the hard parts, that is exactly what the structured  5-week NEET 2026 crash course  at EduAiTutors is built for. Week 3 is a dedicated Biology Power Week  live sessions on every high-yield chapter, daily chapter-wise PYQ sets, and AI-powered mock analysis that tells you precisely which concept gaps to close before the next test.

NEET 2026 is weeks away. The questions are here. Use them.