Official

NEET 2021 Previous Year Question Paper

NEET 2021: the question paper was not released, but the official answer key is here, with a labelled 28-question mock on the 2021 pattern.

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Download NEET 2021 papers

1 official PDF from NTA

NTA did not publish the NEET 2021 question paper, but its official answer key is hosted on this page as a PDF. For timed practice there is a clearly labelled mock paper with original questions in the reported 2021 pattern. The NEET exam covers Physics, Chemistry and Biology.

Explore: NEET hub · Syllabus & pattern · NEET 2025 · How to use PYQs

No official paper released

The conducting body did not publish the NEET 2021 question paper. Practise the NEET 2021 mock paper: original questions modelled on candidate reports, clearly labelled as a mock. The official answer key is hosted below.

Why this year matters

2021 will not mirror every new question type, but it still trains selection, stamina, and the chapters that keep coming back. Biology volume dominates timing. Log Physics and Chemistry misses separately so repair sessions stay focused.

Write down one selection rule you will reuse on exam day: what you attempt first, and what you abandon after a fixed time box.

Paper analysis

Snapshot of NEET 2021

Useful Bio NCERT-fidelity check year.

2021 may feel differently paced than the newest cycle. Borrow stamina and theme lessons; do not copy obsolete section orders or marking quirks.

What this paper stresses

  • Chemistry accuracy under Bio fatigue.
  • NCERT-line questions you overcomplicated.
  • Negative marking on guessed Physics.
  • Biology factual volume versus Physics numerical time.

What to extract before you move on

  • Physics formula-slip vs concept misses.
  • Chem organic/physical pockets that need a dedicated repair block.
  • A timing split you will actually follow (Bio vs PCB balance).
  • Bio chapters with factual bleed (you “knew” it yesterday).

How 2021 sits next to other years

Use 2021 only after NEET 2025, NEET 2024, NEET 2023 are logged. Archive years are for frequency maps, not for predicting tomorrow’s cut-off.

Analyst note: The conducting body did not publish the NEET 2021 paper. The mock below is original practice in the reported pattern; treat coaching “memory-based” papers as unofficial reconstructions.

NEET 2021 mock paper (modelled on the first Section A/B pattern)

This is a mock paper we wrote. The official 2021 paper was never released.The conducting body has not published it. These 28 questions are original, written by previousyearquestions.app to match what candidates and exam analyses reported about the 2021 exam: section mix, topics and difficulty. Use it to practise the pattern. The questions themselves are not from the real exam.

NTA published the NEET (UG) 2021 final answer keys but not the question booklets, as far as we could find on its official sites, so this is an original mock paper. It follows the 12 September 2021 exam: four subjects, each with Section A plus an optional-choice Section B.

What candidates reported about 2021

  • Held on 12 September 2021 (postponed because of COVID-19), conducted by NTA.
  • 16,14,777 candidates registered and 15,44,273 appeared (NTA data).
  • First year of the Section B choice, brought in as COVID-19 relief.
  • Final keys were published for 24 test booklet codes (M1–M6, N1–N6, O1–O6, P1–P6).
  • Each of Physics, Chemistry, Botany and Zoology had Section A (35 compulsory questions) and Section B (15 questions, any 10 to be answered).
  • 200 questions, 180 to be answered, in 200 minutes (3 h 20 min); maximum 720 marks; +4/−1 in both sections.

Suggested time: 27 minutes. Practice mini-paper in the 2021–2024 format: each subject has Section A (answer all) and Section B (answer any 2 of the 3 here; the real paper asked for any 10 of 15). Single-correct MCQs with four options; +4 for a correct answer, −1 for a wrong answer, 0 if unanswered. If you attempt more Section B questions than allowed, only the first ones attempted count, as in the real exam.

Physics

Section A

  1. The acceleration due to gravity at a height equal to the Earth's radius R above the surface is (g = value at surface)

    1. g/2
    2. g/9
    3. g/4
    4. 2g
    Answer and explanation

    Answer: C (g/4)

    g′ = GM/(R + h)² = GM/(2R)² = g/4.

  2. Two 4 Ω resistors in parallel are connected to a cell of emf 2 V and internal resistance 1 Ω. The current drawn from the cell is

    1. 0.5 A
    2. 1 A
    3. 2/3 A
    4. 2 A
    Answer and explanation

    Answer: C (2/3 A)

    4 ∥ 4 = 2 Ω. Total resistance = 2 + 1 = 3 Ω, so I = 2/3 A.

  3. A proton and an α-particle are accelerated from rest through the same potential difference. The ratio of their de Broglie wavelengths λp : λα is

    1. 4 : 1
    2. 1 : 1
    3. 2√2 : 1
    4. 2 : 1
    Answer and explanation

    Answer: C (2√2 : 1)

    λ = h/√(2mqV). λp/λα = √(mα qα / mp qp) = √(4 × 2) = 2√2.

  4. Planck's constant has the same dimensions as

    1. power
    2. energy
    3. angular momentum
    4. linear momentum
    Answer and explanation

    Answer: C (angular momentum)

    h = E/ν has units J s = kg m² s⁻¹, the same as angular momentum (mvr).

Section B

Attempt any 2 of these 3 questions (real paper: any 10 of 15).

  1. A ball is dropped from rest from a height of 20 m (g = 10 m/s²). The time taken to reach the ground is

    1. √2 s
    2. 2 s
    3. 1 s
    4. 4 s
    Answer and explanation

    Answer: B (2 s)

    h = ½gt², so t = √(2h/g) = √(40/10) = 2 s.

  2. A thin convex lens of focal length 20 cm is kept in contact with a thin concave lens of focal length 40 cm. The combination behaves as a

    1. convex lens of focal length 40 cm
    2. convex lens of focal length 13.3 cm
    3. concave lens of focal length 20 cm
    4. concave lens of focal length 40 cm
    Answer and explanation

    Answer: A (convex lens of focal length 40 cm)

    1/F = 1/20 + 1/(−40) = 1/40, so F = +40 cm: a converging lens of focal length 40 cm.

  3. A series LCR circuit with R = 10 Ω is connected to a 100 V (rms) AC source at its resonant frequency. The rms current is

    1. 5 A
    2. 1 A
    3. 10 A
    4. zero
    Answer and explanation

    Answer: C (10 A)

    At resonance XL = XC, so impedance Z = R = 10 Ω and I = 100/10 = 10 A.

Chemistry

Section A

  1. Which of the following contains the largest number of molecules?

    1. 1 g O₂
    2. 1 g N₂
    3. 1 g CO₂
    4. 1 g H₂
    Answer and explanation

    Answer: D (1 g H₂)

    Number of molecules ∝ mass/molar mass. 1/2 (H₂) > 1/28 (N₂) > 1/32 (O₂) > 1/44 (CO₂).

  2. The oxidation state of chromium in K₂Cr₂O₇ is

    1. +3
    2. +12
    3. +6
    4. +7
    Answer and explanation

    Answer: C (+6)

    2(+1) + 2x + 7(−2) = 0, so 2x = 12 and x = +6.

  3. Which of the following gives a positive iodoform test?

    1. Methanol
    2. Benzaldehyde
    3. Ethanol
    4. Propan-1-ol
    Answer and explanation

    Answer: C (Ethanol)

    Iodoform test needs CH₃CO– or CH₃CH(OH)– groups. Ethanol is oxidised by I₂/NaOH to ethanal, which gives CHI₃. The others lack this group.

  4. The ground-state electronic configuration of copper (Z = 29) is

    1. [Ar] 3d¹⁰ 4s²
    2. [Ar] 3d⁹ 4s²
    3. [Ar] 3d¹⁰ 4s¹
    4. [Ar] 3d⁸ 4s² 4p¹
    Answer and explanation

    Answer: C ([Ar] 3d¹⁰ 4s¹)

    A completely filled 3d subshell is extra stable, so one 4s electron moves to 3d: [Ar] 3d¹⁰ 4s¹.

Section B

Attempt any 2 of these 3 questions (real paper: any 10 of 15).

  1. For which of the following processes is ΔS negative?

    1. Freezing of water
    2. Melting of ice
    3. Evaporation of water
    4. Dissolving NaCl in water
    Answer and explanation

    Answer: A (Freezing of water)

    Liquid → solid makes the system more ordered, so entropy decreases.

  2. For the reaction A → products, doubling the concentration of A increases the rate four times. The order with respect to A is

    1. 1
    2. 4
    3. 2
    4. 0
    Answer and explanation

    Answer: C (2)

    Rate = k[A]ⁿ: 2ⁿ = 4, so n = 2.

  3. A solution contains a non-volatile solute with mole fraction 0.2. The relative lowering of vapour pressure of the solvent is

    1. 0.25
    2. 0.8
    3. 1.25
    4. 0.2
    Answer and explanation

    Answer: D (0.2)

    Raoult's law: (p° − p)/p° = x(solute) = 0.2.

Botany

Section A

  1. In C₄ plants, the primary CO₂ acceptor enzyme in mesophyll cells is

    1. RuBisCO
    2. PEP carboxylase
    3. malic enzyme
    4. carbonic anhydrase
    Answer and explanation

    Answer: B (PEP carboxylase)

    PEP carboxylase fixes CO₂ (as HCO₃⁻) on phosphoenolpyruvate in mesophyll cells, forming oxaloacetic acid (C₄).

  2. In angiosperms, the male gametophyte is the

    1. pollen grain
    2. microspore mother cell
    3. stamen
    4. anther
    Answer and explanation

    Answer: A (pollen grain)

    The pollen grain (two- or three-celled at shedding) is the male gametophyte.

  3. Which of the following is a free-living (non-symbiotic) nitrogen-fixing bacterium?

    1. Rhizobium
    2. Glomus
    3. Azotobacter
    4. Frankia
    Answer and explanation

    Answer: C (Azotobacter)

    Azotobacter fixes N₂ while free-living. Rhizobium and Frankia fix nitrogen in root nodules, and Glomus is a mycorrhizal fungus, not a nitrogen fixer.

  4. Out of the 64 codons, how many code for amino acids?

    1. 61
    2. 20
    3. 63
    4. 64
    Answer and explanation

    Answer: A (61)

    Three codons (UAA, UAG, UGA) are stop codons, so 64 − 3 = 61 codons specify amino acids.

Section B

Attempt any 2 of these 3 questions (real paper: any 10 of 15).

  1. In the lac operon of E. coli, the inducer is

    1. glucose
    2. sucrose
    3. lactose (allolactose)
    4. tryptophan
    Answer and explanation

    Answer: C (lactose (allolactose))

    Lactose (as allolactose) binds the repressor and inactivates it, so the structural genes z, y and a are transcribed.

  2. Which of the following is absent in prokaryotic cells?

    1. DNA
    2. Mitochondria
    3. Plasma membrane
    4. Ribosomes
    Answer and explanation

    Answer: B (Mitochondria)

    Prokaryotes lack membrane-bound organelles such as mitochondria; they have 70S ribosomes, a plasma membrane and DNA (nucleoid).

  3. By the 10 per cent law, if producers in a food chain fix 10 000 J, the energy available to tertiary consumers is

    1. 10 J
    2. 1 J
    3. 100 J
    4. 1000 J
    Answer and explanation

    Answer: A (10 J)

    Producers 10 000 → primary consumers 1000 → secondary 100 → tertiary 10 J.

Zoology

Section A

  1. The pacemaker of the human heart is the

    1. AV node
    2. Purkinje fibres
    3. SA node
    4. bundle of His
    Answer and explanation

    Answer: C (SA node)

    The SA node, in the right atrium, generates the most action potentials per minute and sets the heart rhythm.

  2. In early pregnancy the corpus luteum is maintained by

    1. hCG
    2. FSH
    3. oxytocin
    4. relaxin
    Answer and explanation

    Answer: A (hCG)

    hCG from the trophoblast/placenta keeps the corpus luteum secreting progesterone in early pregnancy.

  3. Which of the following pairs is correctly matched?

    1. Klinefelter's syndrome – XO
    2. Down's syndrome – trisomy 21
    3. Turner's syndrome – XXY
    4. Phenylketonuria – X-linked recessive
    Answer and explanation

    Answer: B (Down's syndrome – trisomy 21)

    Down's syndrome is trisomy 21. Turner's is 45, XO; Klinefelter's is 47, XXY; PKU is autosomal recessive.

  4. ADH (vasopressin) increases water reabsorption mainly in the

    1. distal convoluted tubule and collecting duct
    2. proximal convoluted tubule
    3. Bowman's capsule
    4. glomerulus
    Answer and explanation

    Answer: A (distal convoluted tubule and collecting duct)

    ADH increases the water permeability of the DCT and collecting duct, concentrating the urine.

Section B

Attempt any 2 of these 3 questions (real paper: any 10 of 15).

  1. The number of cranial bones in the human skull is

    1. 22
    2. 29
    3. 8
    4. 14
    Answer and explanation

    Answer: C (8)

    The skull has 22 bones: 8 cranial and 14 facial.

  2. Which immunoglobulin crosses the human placenta?

    1. IgM
    2. IgA
    3. IgG
    4. IgE
    Answer and explanation

    Answer: C (IgG)

    IgG is transported across the placenta, giving the foetus passive immunity.

  3. In a population in Hardy–Weinberg equilibrium, 16% of individuals show a recessive trait. The frequency of heterozygotes is

    1. 0.48
    2. 0.24
    3. 0.84
    4. 0.36
    Answer and explanation

    Answer: A (0.48)

    q² = 0.16, so q = 0.4 and p = 0.6. Heterozygotes = 2pq = 2 × 0.6 × 0.4 = 0.48.

Reports this mock is modelled on

How to sit NEET 2021

  1. Work through the mock paper above under exam timing. It follows the reported pattern, but the questions are our own.
  2. Sit the paper under current brochure rules (timers, negatives, NAT/MSQ norms), even if 2021’s interface looked different.
  3. When the clock ends, stop. Review should take at least as long as the attempt.
  4. Fill the error log the same day: section, topic, and miss type (concept, silly, time, or misread).
  5. Next session, repair only logged items. Then pick another year from the decade list.

Other years in this decade

FAQ

Where can I download the official NEET 2021 question paper?

The conducting body did not release it publicly. This page has a clearly labelled mock paper modelled on candidate reports instead.

What does the NEET 2021 paper analysis include?

A year snapshot, what the paper stresses, what to extract into your error log, and how 2021 compares with neighbouring years on this hub.

How should I practise the NEET 2021 previous year paper?

Open the official PDF, sit it timed under current brochure rules, fill an error log the same day, read the paper analysis, then move to another year in the decade list.

Is NEET 2021 still useful if I finished newer papers?

Yes, for theme and weightage mining after your newest papers are logged. Skip deleted syllabus pockets.

Are memory-based NEET 2021 papers reliable?

Treat memory-based sets as interim. Reconcile contested items with official keys or response sheets when the conducting body publishes them.

Where is the NEET syllabus and pattern for this paper?

See the NEET syllabus & pattern page on this hub, and always re-check the latest official brochure before exam day.