NEET 2021 Question PaperPhysics, Chemistry and Biology, with checked answers and solutions
By the RankUp team, founded by Dr. Deepak Sahu (MBBS Gold Medalist, NEET PG AIR 1731) · Updated
173 questions from the NEET 2021 paper, conducted by NTA. Tap an option to check your answer and read why it is right. Each subject has a free PDF with the answer key and explanations.
- Exam
- NEET 2021
- Conducted by
- NTA
- Physics
- 35 questions
- Chemistry
- 42 questions
- Biology
- 96 questions
NEET 2021 Physics questions
35 questions. Tap an option to check your answer.
Q1NEET 2021
A convex lens 'A' of focal length 20 cm and a concave lens 'B' of focal length 5 cm are kept along the same axis with a distance 'd' between them. If a parallel beam of light falling on 'A' leaves 'B' as a parallel beam, then the distance 'd' in cm will be :
Not quite — the answer is B.
For the beam to emerge parallel, the second focal point of the convex lens must coincide with the focal point of the concave lens on the far side. Since the concave lens's focus lies on the incoming side at 5 cm, d = 20 − 5 = 15 cm. Adding the focal lengths (25 cm) would be right only for two convex lenses.
Q2NEET 2021
If force [F], acceleration [A] and time [T] are chosen as the fundamental physical quantities. Find the dimensions of energy.
Not quite — the answer is B.
Energy = force × displacement, and displacement has the dimensions of acceleration × time². Hence [E] = [F][A][T²]. Writing [F][A][T] forgets that distance needs time squared.
Q3NEET 2021
A cup of coffee cools from 90°C to 80°C in t minutes, when the room temperature is 20°C. The time taken by a similar cup of coffee to cool from 80°C to 60°C at a room temperature same at 20°C is :
Not quite — the answer is B.
Using the average form of Newton's law of cooling: 10/t = k(85 − 20) = 65k and 20/t' = k(70 − 20) = 50k. Dividing, t' = (20 × 65)/(10 × 50) t = 2.6t = (13/5)t. The inverse ratio (5/13)t would wrongly suggest the larger, cooler drop takes less time.
Q4NEET 2021
A particle is released from height S from the surface of the Earth. At a certain height its kinetic energy is three times its potential energy. The height from the surface of earth and the speed of the particle at that instant are respectively :
Not quite — the answer is D.
At height h, PE = mgh and KE = mg(S − h). KE = 3PE gives S − h = 3h, so h = S/4. Then v² = 2g(S − h) = 2g(3S/4) = 3gS/2, so v = √(3gS/2); the forms √(3gS)/2 or 3gS/2 are dimensionally or numerically wrong.
Q5NEET 2021
The velocity of a small ball of mass M and density d, when dropped in a container filled with glycerine becomes constant after some time. If the density of glycerine is d/2, then the viscous force acting on the ball will be :
Not quite — the answer is A.
At terminal velocity the net force is zero: weight = buoyant force + viscous force. Ball volume = M/d, so buoyancy = (M/d)(d/2)g = Mg/2, giving viscous force = Mg − Mg/2 = Mg/2. Taking viscous force equal to the full weight Mg ignores buoyancy.
Q6NEET 2021
For a plane electromagnetic wave propagating in x-direction, which one of the following combination gives the correct possible directions for electric field (E) and magnetic field (B) respectively ?
Not quite — the answer is B.
E and B must be perpendicular and E × B must point along +x. For E = −ĵ + k̂ and B = −ĵ − k̂: E·B = 1 − 1 = 0, and E × B = (−ĵ)×(−k̂) + k̂×(−ĵ) = î + î = 2î. The pairs with E and B along the same or opposite lines (such as ĵ + k̂ with −ĵ − k̂) give E × B = 0.
Q7NEET 2021
Column - I gives certain physical terms associated with flow of current through a metallic conductor. Column - II gives some mathematical relations involving electrical quantities. Match Column - I and Column - II with appropriate relations. Column - I | Column - II (a) Drift Velocity | (P) m/(ne²ρ) (b) Electrical Resistivity | (Q) nev_d (c) Relaxation Period | (R) (eE/m)τ (d) Current Density | (S) E/J
Not quite — the answer is A.
Drift velocity v_d = (eE/m)τ; resistivity ρ = E/J; relaxation time τ = m/(ne²ρ); current density J = nev_d. So drift velocity–(eE/m)τ, resistivity–E/J, relaxation period–m/(ne²ρ), current density–nev_d.
Q8NEET 2021
A spring is stretched by 5 cm by a force 10 N. The time period of the oscillations when a mass of 2 kg is suspended by it is :
Not quite — the answer is D.
k = F/x = 10/0.05 = 200 N/m. T = 2π√(m/k) = 2π√(2/200) = 2π × 0.1 = 0.628 s. 6.28 s would result from forgetting to convert 5 cm into metres.
Q9NEET 2021
A parallel plate capacitor has a uniform electric field 'E' in the space between the plates. If the distance between the plates is 'd' and the area of each plate is 'A', the energy stored in the capacitor is : (ε₀ = permittivity of free space)
Not quite — the answer is C.
Energy density in the field is (1/2)ε₀E², and the field fills a volume Ad between the plates. So U = (1/2)ε₀E²Ad. The expression (1/2)ε₀E² alone is only energy per unit volume.
Q10NEET 2021
A radioactive nucleus ᴬZX undergoes spontaneous decay in the sequence ᴬZX → (Z−1)B → (Z−3)C → (Z−2)D, where Z is the atomic number of element X. The possible decay particles in the sequence are :
Not quite — the answer is C.
Z → Z − 1: atomic number falls by 1 with no other change, which is β⁺ emission. Z − 1 → Z − 3: falls by 2, which is α emission. Z − 3 → Z − 2: rises by 1, which is β⁻ emission. So the sequence is β⁺, α, β⁻.
Q11NEET 2021
The escape velocity from the Earth's surface is v. The escape velocity from the surface of another planet having a radius, four times that of Earth and same mass density is :
Not quite — the answer is D.
v_e = √(2GM/R) with M = (4/3)πR³ρ gives v_e = R√(8πGρ/3), so v_e ∝ R at fixed density. Four times the radius gives 4v. Answering 2v uses v_e ∝ √R, which holds only at fixed mass, not fixed density.
Q12NEET 2021
A screw gauge gives the following readings when used to measure the diameter of a wire Main scale reading : 0 mm Circular scale reading : 52 divisions Given that 1 mm on main scale corresponds to 100 divisions on the circular scale. The diameter of the wire from the above data is :
Not quite — the answer is D.
Least count = 1 mm/100 = 0.01 mm. Diameter = 0 + 52 × 0.01 mm = 0.52 mm = 0.052 cm. The trap 0.52 cm forgets the mm-to-cm conversion.
Q13NEET 2021
Water falls from a height of 60 m at the rate of 15 kg/s to operate a turbine. The losses due to frictional force are 10% of the input energy. How much power is generated by the turbine ? (g = 10 m/s²)
Not quite — the answer is B.
Input power = (mass per second) × g × h = 15 × 10 × 60 = 9000 W. With 10% loss, output = 0.9 × 9000 = 8100 W = 8.1 kW.
Q14NEET 2021
A small block slides down on a smooth inclined plane, starting from rest at time t = 0. Let Sₙ be the distance travelled by the block in the interval t = n − 1 to t = n. Then, the ratio Sₙ/Sₙ₊₁ is :
Not quite — the answer is B.
Starting from rest with constant acceleration a, distance in the nth second Sₙ = (a/2)(2n − 1), and Sₙ₊₁ = (a/2)(2n + 1). So Sₙ/Sₙ₊₁ = (2n − 1)/(2n + 1); the reverse ratio is greater than 1, impossible for an accelerating block.
Q15NEET 2021
Polar molecules are the molecules :
Not quite — the answer is D.
In polar molecules such as H₂O and HCl the centres of positive and negative charge do not coincide, so they have a permanent dipole moment even without an external field. Acquiring a dipole only in an applied field describes non-polar molecules (induced dipoles).
Q16NEET 2021
In a potentiometer circuit a cell of EMF 1.5 V gives balance point at 36 cm length of wire. If another cell of EMF 2.5 V replaces the first cell, then at what length of the wire, the balance point occurs ?
Not quite — the answer is A.
With the same driver circuit, the balancing length is proportional to the EMF: l₂ = 36 × (2.5/1.5) = 60 cm. 21.6 cm results from inverting the ratio.
Q17NEET 2021
Two charged spherical conductors of radius R₁ and R₂ are connected by a wire. Then the ratio of surface charge densities of the spheres (σ₁/σ₂) is :
Not quite — the answer is B.
Connected conductors reach a common potential: kQ₁/R₁ = kQ₂/R₂, so Q ∝ R. Since σ = Q/(4πR²) ∝ 1/R, σ₁/σ₂ = R₂/R₁. Charge is proportional to R, but surface density is inversely proportional to R.
Q18NEET 2021
An electromagnetic wave of wavelength 'λ' is incident on a photosensitive surface of negligible work function. If 'm' mass is of photoelectron emitted from the surface has de-Broglie wavelength λd, then :
Not quite — the answer is C.
With negligible work function, hc/λ = K = p²/2m and p = h/λd. So hc/λ = h²/(2mλd²), giving λ = (2mc/h)λd². Check dimensions: mc/h has units of 1/length, so (mc/h)λd² is a length.
Q19NEET 2021
The electron concentration in an n-type semiconductor is the same as hole concentration in a p-type semiconductor. An external field (electric) is applied across each of them. Compare the currents in them.
Not quite — the answer is C.
Current density J = neμE; with equal carrier concentration and the same field, the current depends on mobility. Electrons have higher mobility than holes, so the n-type sample carries more current. Holes do conduct, so p-type current is not zero.
Q20NEET 2021
The number of photons per second on an average emitted by the source of monochromatic light of wavelength 600 nm, when it delivers the power of 3.3 × 10⁻³ watt will be : (h = 6.6 × 10⁻³⁴ Js)
Not quite — the answer is C.
Photon energy E = hc/λ = (6.6 × 10⁻³⁴ × 3 × 10⁸)/(600 × 10⁻⁹) = 3.3 × 10⁻¹⁹ J. Number per second = P/E = (3.3 × 10⁻³)/(3.3 × 10⁻¹⁹) = 10¹⁶.
Q21NEET 2021
If E and G respectively denote energy and gravitational constant, then E/G has the dimensions of :
Not quite — the answer is A.
[E] = ML²T⁻² and [G] = M⁻¹L³T⁻². So E/G = M²L⁻¹T⁰. Forgetting that G carries M⁻¹ would give a single power of mass.
Q22NEET 2021
The effective resistance of a parallel connection that consists of four wires of equal length, equal area of cross-section and same material is 0.25 Ω. What will be the effective resistance if they are connected in series ?
Not quite — the answer is D.
Four identical wires of resistance R in parallel give R/4 = 0.25 Ω, so R = 1 Ω. In series the resistance is 4R = 4 Ω (16 times the parallel value).
Q23NEET 2021
The half-life of a radioactive nuclide is 100 hours. The fraction of original activity that will remain after 150 hours would be :
Not quite — the answer is B.
150 h is 1.5 half-lives, so the fraction of activity remaining is (1/2)^1.5 = 1/(2√2) ≈ 0.354. Linear interpolation between 1/2 and 1/4 is wrong because decay is exponential.
Q24NEET 2021
A nucleus with mass number 240 breaks into two fragments each of mass number 120, the binding energy per nucleon of unfragmented nuclei is 7.6 MeV while that of fragments is 8.5 MeV. The total gain in the Binding Energy in the process is :
Not quite — the answer is D.
Initial binding energy = 240 × 7.6 = 1824 MeV; final = 2 × 120 × 8.5 = 2040 MeV. Gain = 2040 − 1824 = 216 MeV. 0.9 MeV is only the change per nucleon, not the total.
Q25NEET 2021
Two conducting circular loops of radii R₁ and R₂ are placed in the same plane with their centres coinciding. If R₁ >> R₂, the mutual inductance M between them will be directly proportional to :
Not quite — the answer is D.
A current I in the large loop gives B = μ₀I/(2R₁) at its centre, nearly uniform over the small loop. Flux through the small loop = (μ₀I/2R₁)πR₂², so M = μ₀πR₂²/(2R₁) ∝ R₂²/R₁.
Q26NEET 2021
In the product F⃗ = q(v⃗ × B⃗) = q v⃗ × (B î + B ĵ + B₀ k̂) For q = 1 and v⃗ = 2î + 4ĵ + 6k̂ and F⃗ = 4î − 20ĵ + 12k̂ What will be the complete expression for B⃗ ?
Not quite — the answer is B.
With B = Bî + Bĵ + B₀k̂ and v = 2î + 4ĵ + 6k̂: v × B = (4B₀ − 6B)î + (6B − 2B₀)ĵ + (2B − 4B)k̂. Matching the k̂ term, −2B = 12 so B = −6; matching î, 4B₀ + 36 = 4 so B₀ = −8. Check ĵ: −36 + 16 = −20, so B = −6î − 6ĵ − 8k̂.
Q27NEET 2021
A series LCR circuit containing 5.0 H inductor, 80 μF capacitor and 40 Ω resistor is connected to 230 V variable frequency ac source. The angular frequencies of the source at which power transferred to the circuit is half the power at the resonant angular frequency are likely to be :
Not quite — the answer is C.
ω₀ = 1/√(LC) = 1/√(5 × 80 × 10⁻⁶) = 1/0.02 = 50 rad/s. Half-power frequencies are ω₀ ± R/(2L) = 50 ± 40/10 = 50 ± 4, i.e. 46 rad/s and 54 rad/s.
Q28NEET 2021
A car starts from rest and accelerates at 5 m/s². At t = 4 s, a ball is dropped out of a window by a person sitting in the car. What is the velocity and acceleration of the ball at t = 6 s ? (Take g = 10 m/s²)
Not quite — the answer is D.
At t = 4 s the car's speed is 5 × 4 = 20 m/s, which the ball keeps horizontally. After 2 s of free fall its vertical speed is 10 × 2 = 20 m/s, so v = √(20² + 20²) = 20√2 m/s. Once released, only gravity acts, so its acceleration is g = 10 m/s², not the car's 5 m/s².
Q29NEET 2021
Twenty seven drops of same size are charged at 220 V each. They combine to form a bigger drop. Calculate the potential of the bigger drop.
Not quite — the answer is D.
Volume conservation: R = 27^(1/3) r = 3r; charge Q = 27q. V = kQ/R = (27/3)kq/r = 9 × 220 = 1980 V. Multiplying by 3 (660 V) uses the radius ratio instead of n^(2/3).
Q30NEET 2021
A uniform conducting wire of length 12a and resistance 'R' is wound up as a current carrying coil in the shape of, (i) an equilateral triangle of side 'a'. (ii) a square of side 'a'. The magnetic dipole moments of the coil in each case respectively are :
Not quite — the answer is A.
Triangle: each turn uses 3a, so 12a gives 4 turns of area (√3/4)a², and m = 4I(√3/4)a² = √3 Ia². Square: each turn uses 4a, so 3 turns of area a², and m = 3Ia².
Q31NEET 2021
A ball of mass 0.15 kg is dropped from a height 10 m, strikes the ground and rebounds to the same height. The magnitude of impulse imparted to the ball is (g = 10 m/s²) nearly :
Not quite — the answer is B.
Speed just before impact v = √(2gh) = √200 ≈ 14.1 m/s; it rebounds to the same height, so it leaves with 14.1 m/s upward. Impulse = change in momentum = 2mv = 2 × 0.15 × 14.1 ≈ 4.2 kg m/s. 2.1 kg m/s ignores the reversal of direction.
Q32NEET 2021
A step down transformer connected to an ac mains supply of 220 V is made to operate at 11 V, 44 W lamp. Ignoring power losses in the transformer, what is the current in the primary circuit ?
Not quite — the answer is A.
For an ideal transformer input power equals output power, 44 W. Primary current = P/V = 44/220 = 0.2 A. 4 A is the secondary (lamp) current, 44/11.
Q33NEET 2021
A particle moving in a circle of radius R with a uniform speed takes a time T to complete one revolution. If this particle were projected with the same speed at an angle 'θ' to the horizontal, the maximum height attained by it equals 4R. The angle of projection, θ, is then given by :
Not quite — the answer is D.
Speed v = 2πR/T. Maximum height H = v²sin²θ/(2g) = 4R gives sin²θ = 8gR/v² = 8gR·T²/(4π²R²) = 2gT²/(π²R). Hence θ = sin⁻¹(2gT²/π²R)^(1/2).
Q34NEET 2021
A particle of mass 'm' is projected with a velocity v = kVe (k < 1) from the surface of the earth. (Ve = escape velocity) The maximum height above the surface reached by the particle is :
Not quite — the answer is D.
Energy conservation: (1/2)mk²(2GM/R) − GMm/R = −GMm/(R + h). This gives 1/(R + h) = (1 − k²)/R, so R + h = R/(1 − k²) and h = Rk²/(1 − k²). Using the flat-earth formula v²/2g would wrongly give h = k²R.
Q35NEET 2021
From a circular ring of mass 'M' and radius 'R' an arc corresponding to a 90° sector is removed. The moment of inertia of the remaining part of the ring about an axis passing through the centre of the ring and perpendicular to the plane of the ring is 'K' times 'MR²'. Then the value of 'K' is :
Not quite — the answer is A.
Every element of a ring is at distance R from the central perpendicular axis, so I = (mass) × R². Removing a 90° arc leaves 3/4 of the mass, so I = (3/4)MR² and K = 3/4.
Chapter-wise split of NEET 2021 Physics
- Units and Measurements3 Q
- Current Electricity3 Q
- Electrostatic Potential and Capacitance3 Q
- Nuclei3 Q
- Work, Energy and Power2 Q
- Gravitation2 Q
- Dual Nature of Radiation and Matter2 Q
- Moving Charges and Magnetism2 Q
- Alternating Current2 Q
- Motion in a Plane2 Q
- Ray Optics and Optical Instruments1 Q
- Thermal Properties of Matter1 Q
- Mechanical Properties of Fluids1 Q
- Electromagnetic Waves1 Q
- Oscillations1 Q
- Motion in a Straight Line1 Q
- Electric Charges and Fields1 Q
- Semiconductor Electronics: Materials, Devices and Simple Circuits1 Q
- Electromagnetic Induction1 Q
- Laws of Motion1 Q
- System of Particles and Rotational Motion1 Q
NEET 2021 Chemistry questions
32 questions. Tap an option to check your answer.
Q1NEET 2021
Which one among the following is the correct option for right relationship between Cp and Cv for one mole of ideal gas ?
Not quite — the answer is B.
For one mole of an ideal gas, C_p exceeds C_v by the work done in expansion at constant pressure, which is R per kelvin. So Mayer's relation is C_p − C_v = R; a product relation like C_p = RC_v is dimensionally inconsistent.
Q2NEET 2021
The major product formed in dehydrohalogenation reaction of 2-Bromo pentane is Pent-2-ene. This product formation is based on ?
Not quite — the answer is A.
In base-induced dehydrohalogenation, the more substituted (more stable) alkene is the main product, which is Saytzeff's rule. Pent-2-ene is more substituted than pent-1-ene. Hofmann's rule predicts the less substituted alkene and applies to bulky bases or quaternary ammonium bases.
Q3NEET 2021
The compound which shows metamerism is :
Not quite — the answer is D.
Metamerism arises when different alkyl groups are attached to the same polyvalent functional group, e.g. ethers. C₄H₁₀O gives CH₃–O–C₃H₇ and C₂H₅–O–C₂H₅, which are metamers. C₃H₈O has only one ether (CH₃OC₂H₅), so it cannot show metamerism.
Q4NEET 2021
BF₃ is planar and electron deficient compound. Hybridization and number of electrons around the central atom, respectively are :
Not quite — the answer is C.
Boron in BF₃ forms three σ bonds and has no lone pair, so it is sp² hybridised and trigonal planar. It has only 6 electrons in its valence shell, which is why it is electron deficient; 8 would complete the octet.
Q5NEET 2021
The major product of the following chemical reaction is : (CH₃)₂CH–CH=CH₂ + HBr —(C₆H₅CO)₂O₂→ ?
Not quite — the answer is A.
Benzoyl peroxide makes HBr add by a free-radical chain (peroxide or Kharasch effect), giving anti-Markovnikov addition. Br adds to the terminal CH₂ so that the more stable secondary radical forms, giving (CH₃)₂CH–CH₂–CH₂–Br. The Markovnikov product (CH₃)₂CH–CH(Br)–CH₃ would form without peroxide.
Q6NEET 2021
Dihedral angle of least stable conformer of ethane is :
Not quite — the answer is D.
The least stable conformer of ethane is the eclipsed form, where the C–H bonds on adjacent carbons line up and torsional strain is maximum; its dihedral angle is 0°. 60° corresponds to the most stable staggered form.
Q7NEET 2021
The following solutions were prepared by dissolving 10 g of glucose (C₆H₁₂O₆) in 250 ml of water (P₁), 10 g of urea (CH₄N₂O) in 250 ml of water (P₂) and 10 g of sucrose (C₁₂H₂₂O₁₁) in 250 ml of water (P₃). The right option for the decreasing order of osmotic pressure of these solutions is :
Not quite — the answer is A.
π = (w/M)RT/V; with the same mass and volume, π ∝ 1/M. Molar masses: urea 60, glucose 180, sucrose 342 g/mol. So π(urea) > π(glucose) > π(sucrose), i.e. P₂ > P₁ > P₃.
Q8NEET 2021
Zr (Z = 40) and Hf (Z = 72) have similar atomic and ionic radii because of :
Not quite — the answer is C.
Between Zr (4d) and Hf (5d) the fourteen 4f elements are filled; poor shielding by 4f electrons causes the lanthanoid contraction, cancelling the expected size increase. Being in the same group alone would predict Hf to be larger.
Q9NEET 2021
The molar conductance of NaCl, HCl and CH₃COONa at infinite dilution are 126.45, 426.16 and 91.0 S cm² mol⁻¹ respectively. The molar conductance of CH₃COOH at infinite dilution is. Choose the right option for your answer.
Not quite — the answer is B.
Kohlrausch's law: Λ°(CH₃COOH) = Λ°(CH₃COONa) + Λ°(HCl) − Λ°(NaCl) = 91.0 + 426.16 − 126.45 = 390.71 S cm² mol⁻¹. Simply adding all three gives 643.61, which is not the right combination.
Q10NEET 2021
A particular station of All India Radio, New Delhi, broadcasts on a frequency of 1,368 kHz (kilohertz). The wavelength of the electromagnetic radiation emitted by the transmitter is : [speed of light, c = 3.0 × 10⁸ ms⁻¹]
Not quite — the answer is A.
λ = c/ν = (3.0 × 10⁸)/(1368 × 10³) = 219.30 m. 2192 m results from a decimal slip; the value 219.2 m is a rounding error.
Q11NEET 2021
Ethylene diaminetetraacetate (EDTA) ion is :
Not quite — the answer is A.
EDTA⁴⁻ donates through its two amine nitrogen atoms and four carboxylate oxygen atoms, so it is a hexadentate ligand. Ethylenediamine (en), not EDTA, is the bidentate ligand with two N donors.
Q12NEET 2021 · Q53
Noble gases are named because of their inertness towards reactivity. Identify an incorrect statement about them.
Not quite — the answer is B.
Noble gases are monatomic and held only by weak dispersion forces, so their melting and boiling points are very low, not high. They are sparingly soluble in water and have large positive electron gain enthalpy because their shells are full.
Q13NEET 2021
The correct sequence of bond enthalpy of 'C–X' bond is :
Not quite — the answer is B.
As the halogen gets larger (F < Cl < Br < I), the C–X bond becomes longer and overlap poorer, so bond enthalpy decreases: CH₃–F > CH₃–Cl > CH₃–Br > CH₃–I. This is why C–I bonds break most easily.
Q14NEET 2021
The pKb of dimethylamine and pKa of acetic acid are 3.27 and 4.77 respectively at T (K). The correct option for the pH of dimethylammonium acetate solution is :
Not quite — the answer is C.
For a salt of a weak acid and weak base, pH = 7 + (pKa − pKb)/2 = 7 + (4.77 − 3.27)/2 = 7 + 0.75 = 7.75. The solution is slightly basic because dimethylamine (pKb 3.27) is a stronger base than acetic acid is an acid.
Q15NEET 2021
Match List - I with List - II. List - I | List - II (a) PCl₅ | (i) Square pyramidal (b) SF₆ | (ii) Trigonal planar (c) BrF₅ | (iii) Octahedral (d) BF₃ | (iv) Trigonal bipyramidal Choose the correct answer from the options given below.
Not quite — the answer is A.
PCl₅: 5 bond pairs, trigonal bipyramidal. SF₆: 6 bond pairs, octahedral. BrF₅: 5 bond pairs + 1 lone pair, square pyramidal. BF₃: 3 bond pairs, trigonal planar.
Q16NEET 2021
Statement I : Acid strength increases in the order given as HF << HCl << HBr << HI. Statement II : As the size of the elements F, Cl, Br, I increases down the group, the bond strength of HF, HCl, HBr and HI decreases and so the acid strength increases. In the light of the above statements, choose the correct answer from the options given below.
Not quite — the answer is A.
Acid strength of hydrogen halides increases HF < HCl < HBr < HI. This is because the halogen size increases down the group, the H–X bond becomes longer and weaker, and H⁺ is released more easily. Both statements are true.
Q17NEET 2021
Identify the compound that will react with Hinsberg's reagent to give a solid which dissolves in alkali.
Not quite — the answer is C.
A primary amine (CH₃CH₂NH₂) reacts with benzenesulphonyl chloride to give N-ethylbenzenesulphonamide, whose N–H is acidic, so it dissolves in alkali. The secondary amine gives a sulphonamide without N–H (insoluble in alkali), and tertiary amines and nitroalkanes do not react.
Q18NEET 2021
What is the IUPAC name of the organic compound formed in the following chemical reaction ? Acetone —[(i) C₂H₅MgBr, dry Ether; (ii) H₂O, H⁺]→ Product
Not quite — the answer is D.
C₂H₅MgBr adds to the carbonyl carbon of acetone, and hydrolysis gives the tertiary alcohol (CH₃)₂C(OH)CH₂CH₃. Its longest chain has four carbons with OH and CH₃ on C-2: 2-methylbutan-2-ol. 2-methylpropan-2-ol would come from CH₃MgBr.
Q19NEET 2021
Which of the following reactions is the metal displacement reaction ? Choose the right option.
Not quite — the answer is B.
In Cr₂O₃ + 2Al → Al₂O₃ + 2Cr, aluminium displaces chromium metal from its oxide, a metal displacement reaction. Fe + 2HCl displaces hydrogen, not a metal, and the other two are decomposition reactions.
Q20NEET 2021
The incorrect statement among the following is :
Not quite — the answer is B.
Most trivalent lanthanoid ions are coloured in the solid state and in solution because of f–f transitions (La³⁺ and Lu³⁺ are exceptions), so calling them colourless is the incorrect statement. Actinoid contraction from element to element is indeed greater, because 5f electrons shield poorly.
Q21NEET 2021
The RBC deficiency is deficiency disease of :
Not quite — the answer is A.
Vitamin B₁₂ is needed for red blood cell formation; its deficiency causes pernicious anaemia. Vitamin B₁ deficiency causes beriberi and B₂ deficiency causes cheilosis, not an RBC deficiency.
Q22NEET 2021
CH₃CH₂COO⁻Na⁺ —(NaOH, + ?; Heat)→ CH₃CH₃ + Na₂CO₃. Consider the above reaction and identify the missing reagent/chemical.
Not quite — the answer is C.
Heating a sodium carboxylate with soda lime (NaOH + CaO) removes CO₂ as Na₂CO₃ and gives an alkane with one carbon fewer: sodium propanoate → ethane. The missing reagent is CaO; red phosphorus is used with HI or in HVZ halogenation.
Q23NEET 2021
Match List - I with List - II. List - I | List - II (a) [Fe(CN)₆]³⁻ | (i) 5.92 BM (b) [Fe(H₂O)₆]³⁺ | (ii) 0 BM (c) [Fe(CN)₆]⁴⁻ | (iii) 4.90 BM (d) [Fe(H₂O)₆]²⁺ | (iv) 1.73 BM Choose the correct answer from the options given below.
Not quite — the answer is D.
[Fe(CN)₆]³⁻: Fe³⁺ (d⁵) low spin, 1 unpaired electron, 1.73 BM. [Fe(H₂O)₆]³⁺: high spin d⁵, 5 unpaired, 5.92 BM. [Fe(CN)₆]⁴⁻: Fe²⁺ (d⁶) low spin, 0 unpaired, 0 BM. [Fe(H₂O)₆]²⁺: high spin d⁶, 4 unpaired, 4.90 BM.
Q24NEET 2021
From the following pairs of ions which one is not an iso-electronic pair ?
Not quite — the answer is D.
Fe²⁺ has 26 − 2 = 24 electrons, Mn²⁺ has 25 − 2 = 23, so they are not isoelectronic. O²⁻/F⁻ and Na⁺/Mg²⁺ each have 10 electrons, and Mn²⁺/Fe³⁺ each have 23.
Q25NEET 2021
The reagent 'R' in the given sequence of chemical reaction is : 2,4,6-Tribromoaniline —(NaNO₂, HCl, 0–5°C)→ 2,4,6-Tribromobenzenediazonium chloride —R→ 1,3,5-Tribromobenzene
Not quite — the answer is B.
Ethanol (like H₃PO₂) reduces an arenediazonium salt, replacing –N₂⁺Cl⁻ by –H and itself being oxidised to ethanal. This converts 2,4,6-tribromobenzenediazonium chloride into 1,3,5-tribromobenzene. Water would give a phenol and CuCN/KCN a nitrile.
Q26NEET 2021
Which of the following molecules is non-polar in nature ?
Not quite — the answer is C.
SbCl₅ is trigonal bipyramidal with five identical Sb–Cl bonds, so the bond dipoles cancel and the molecule is non-polar. POCl₃ (unequal P=O and P–Cl bonds), CH₂O (trigonal planar with C=O) and bent NO₂ all have net dipoles.
Q27NEET 2021
The correct option for the value of vapour pressure of a solution at 45°C with benzene to octane in molar ratio 3 : 2 is : [At 45°C vapour pressure of benzene is 280 mm Hg and that of octane is 420 mm Hg. Assume Ideal gas]
Not quite — the answer is C.
Mole fractions: benzene 3/5 = 0.6, octane 2/5 = 0.4. By Raoult's law P = 0.6 × 280 + 0.4 × 420 = 168 + 168 = 336 mm Hg. 168 mm Hg is only one component's partial pressure.
Q28NEET 2021
The molar conductivity of 0.007 M acetic acid is 20 S cm² mol⁻¹. What is the dissociation constant of acetic acid ? Choose the correct option. [Λ°(H⁺) = 350 S cm² mol⁻¹, Λ°(CH₃COO⁻) = 50 S cm² mol⁻¹]
Not quite — the answer is C.
Λ°m = 350 + 50 = 400 S cm² mol⁻¹, so α = Λm/Λ°m = 20/400 = 0.05. Ka = cα²/(1 − α) ≈ 0.007 × 0.0025 = 1.75 × 10⁻⁵ mol L⁻¹ (exactly 1.84 × 10⁻⁵ without approximation, still nearest).
Q29NEET 2021
The slope of Arrhenius Plot (ln k v/s 1/T) of first order reaction is −5 × 10³ K. The value of Ea of the reaction is. Choose the correct option for your answer. [Given R = 8.314 JK⁻¹ mol⁻¹]
Not quite — the answer is A.
ln k = ln A − Ea/(RT), so the slope of ln k vs 1/T is −Ea/R. Ea = 5 × 10³ × 8.314 = 41,570 J mol⁻¹ ≈ 41.5 kJ mol⁻¹. Ea is positive since the slope is negative, and 83 kJ is double the correct value.
Q30NEET 2021
Match List - I with List - II. List - I | List - II (a) C₆H₆ —(CO, HCl; Anhyd. AlCl₃/CuCl)→ | (i) Hell-Volhard-Zelinsky reaction (b) R–CO–CH₃ + NaOX → | (ii) Gattermann-Koch reaction (c) R–CH₂–OH + R'COOH —(Conc. H₂SO₄)→ | (iii) Haloform reaction (d) R–CH₂COOH —((i) X₂/Red P; (ii) H₂O)→ | (iv) Esterification Choose the correct answer from the options given below.
Not quite — the answer is D.
Benzene + CO/HCl with AlCl₃/CuCl gives benzaldehyde (Gattermann-Koch). A methyl ketone with NaOX gives haloform (haloform reaction). Alcohol + carboxylic acid with conc. H₂SO₄ gives an ester (esterification). An acid with X₂/red P gives an α-halo acid (Hell-Volhard-Zelinsky).
Q31NEET 2021
The intermediate compound 'X' in the following chemical reaction is : C₆H₅–CH₃ + CrO₂Cl₂ —CS₂→ X —H₃O⁺→ C₆H₅–CHO
Not quite — the answer is A.
In the Etard reaction, chromyl chloride in CS₂ converts the methyl group of toluene into a brown chromium complex, C₆H₅CH(OCrOHCl₂)₂, which is hydrolysed to benzaldehyde. The diacetate C₆H₅CH(OCOCH₃)₂ is the intermediate of the CrO₃/acetic anhydride route, not chromyl chloride.
Q32NEET 2021
For irreversible expansion of an ideal gas under isothermal condition, the correct option is :
Not quite — the answer is C.
For an ideal gas, internal energy depends only on temperature, so ΔU = 0 in any isothermal process. An irreversible process always increases the total entropy of system + surroundings, so ΔS(total) > 0. ΔS(total) = 0 holds only for a reversible process.
Chemistry: not in the current NEET syllabus
These 10 questions are from topics NCERT dropped in its 2023 revision. Shown for completeness; you can skip them for NEET 2027.
10 questions. Tap an option to check your answer.
Q1NEET 2021 · Q52
The correct option for the number of body centred unit cells in all 14 types of Bravais lattice unit cells is :
Not quite — the answer is D.
Body-centred unit cells occur in only three of the 14 Bravais lattices: cubic, tetragonal and orthorhombic. Monoclinic has end-centred but not body-centred, so the count is 3.
Q2NEET 2021 · Q57
The right option for the statement "Tyndall effect is exhibited by", is :
Not quite — the answer is C.
Tyndall effect is the scattering of light by colloidal particles. Starch forms a colloidal (lyophilic) sol, whereas NaCl, glucose and urea form true solutions whose particles are too small to scatter light.
Q3NEET 2021 · Q58
Among the following alkaline earth metal halides, one which is covalent and soluble in organic solvents is :
Not quite — the answer is D.
Be²⁺ is very small and highly polarising, so BeCl₂ has largely covalent character and dissolves in organic solvents. The chlorides of Mg, Ca and Sr are ionic.
Q4NEET 2021 · Q59
Which one of the following methods can be used to obtain highly pure metal which is liquid at room temperature ?
Not quite — the answer is C.
Distillation purifies low-boiling metals such as mercury (liquid at room temperature) and zinc: the metal is vaporised and condensed, leaving impurities behind. Zone refining is for semiconductors like Si and Ge, which are solids.
Q5NEET 2021 · Q61
Which one of the following polymers is prepared by addition polymerisation ?
Not quite — the answer is A.
Teflon is formed by addition polymerisation of tetrafluoroethene (CF₂=CF₂). Nylon-66, Novolac and Dacron are condensation polymers that eliminate small molecules such as water.
Q6NEET 2021 · Q66
The maximum temperature that can be achieved in blast furnace is :
Not quite — the answer is B.
In the lower zone of the blast furnace, coke burns in a blast of preheated air and the temperature reaches about 2200 K, the maximum in the furnace. Around 1200 K and below are typical of the upper reduction zones.
Q7NEET 2021 · Q75
The structures of beryllium chloride in solid state and vapour phase, are :
Not quite — the answer is A.
Solid BeCl₂ has a polymeric chain structure with chlorine bridges. In the vapour phase it exists mainly as a chlorine-bridged dimer, which dissociates to the linear monomer only at very high temperature (about 1200 K).
Q8NEET 2021 · Q76
Given below are two statements : Statement I : Aspirin and Paracetamol belong to the class of narcotic analgesics. Statement II : Morphine and Heroin are non-narcotic analgesics. In the light of the above statements, choose the correct answer from the options given below.
Not quite — the answer is B.
Aspirin and paracetamol are non-narcotic analgesics, while morphine and heroin are narcotic analgesics. Each statement swaps the classes, so both are false.
Q9NEET 2021 · Q85
Tritium, a radioactive isotope of hydrogen, emits which of the following particles ?
Not quite — the answer is A.
Tritium (³H) is radioactive and decays by emitting low-energy β⁻ particles, becoming ³He (half-life about 12.3 years). It does not emit alpha particles or neutrons.
Q10NEET 2021 · Q92
Choose the correct option for the total pressure (in atm.) in a mixture of 4 g O₂ and 2 g H₂ confined in a total volume of one litre at 0°C is : [Given R = 0.082 L atm mol⁻¹ K⁻¹, T = 273 K]
Not quite — the answer is C.
Moles: O₂ = 4/32 = 0.125 and H₂ = 2/2 = 1, total 1.125 mol. P = nRT/V = 1.125 × 0.082 × 273/1 = 25.18 atm. 2.518 is a decimal slip.
Chapter-wise split of NEET 2021 Chemistry
- Chemical Bonding and Molecular Structure3 Q
- Hydrocarbons3 Q
- Aldehydes, Ketones and Carboxylic Acids3 Q
- Thermodynamics2 Q
- Haloalkanes and Haloarenes2 Q
- Solutions2 Q
- The d- and f-Block Elements2 Q
- Electrochemistry2 Q
- Coordination Compounds2 Q
- Equilibrium2 Q
- Amines2 Q
- Organic Chemistry: Some Basic Principles and Techniques1 Q
- Structure of Atom1 Q
- Redox Reactions1 Q
- Biomolecules1 Q
- Classification of Elements and Periodicity in Properties1 Q
- Chemical Kinetics1 Q
NEET 2021 Biology questions
79 questions. Tap an option to check your answer.
Q1NEET 2021
In the equation GPP − R = NPP R represents :
Not quite — the answer is D.
Net primary productivity is what remains of gross primary productivity after the producers' own respiration losses are subtracted, so R stands for respiration. Radiant energy is the input that drives GPP, not something subtracted from it.
Q2NEET 2021
Inspite of interspecific competition in nature, which mechanism the competing species might have evolved for their survival ?
Not quite — the answer is A.
Competing species can coexist by resource partitioning, using the same resource in different ways, places or times, as MacArthur showed for warblers feeding in different parts of the same tree. Competitive release is the expansion of a species once its competitor is removed, not a coexistence mechanism.
Q3NEET 2021
Amensalism can be represented as :
Not quite — the answer is A.
In amensalism one species is harmed while the other is neither benefited nor harmed, giving the (−, 0) pattern. The (+, 0) pattern is commensalism and (+, +) is mutualism.
Q4NEET 2021
Match List - I with List - II. List - I | List - II (a) Cells with active cell division capacity | (i) Vascular tissues (b) Tissue having all cells similar in structure and function | (ii) Meristematic tissue (c) Tissue having different types of cells | (iii) Sclereids (d) Dead cells with highly thickened walls and narrow lumen | (iv) Simple tissue Select the correct answer from the options given below.
Not quite — the answer is A.
Actively dividing cells make up meristematic tissue, a tissue of one cell type is a simple tissue, a tissue made of different cell types (xylem, phloem) is complex vascular tissue, and dead cells with very thick walls and a narrow lumen are sclereids. Hence (a)-(ii), (b)-(iv), (c)-(i), (d)-(iii).
Q5NEET 2021
The production of gametes by the parents, formation of zygotes, the F₁ and F₂ plants, can be understood from a diagram called :
Not quite — the answer is C.
The Punnett square, devised by Reginald C. Punnett, is the checkerboard diagram that shows gametes of both parents and the zygote combinations of the F₁ and F₂ generations. The other names are not real genetic terms.
Q6NEET 2021
DNA strands on a gel stained with ethidium bromide when viewed under UV radiation, appear as :
Not quite — the answer is B.
Ethidium bromide intercalates into DNA and fluoresces under UV light, so the separated DNA fragments are seen as bright orange bands. They are not visible as bands without the stain and UV exposure.
Q7NEET 2021
Gemmae are present in :
Not quite — the answer is D.
Gemmae are green, multicellular asexual buds formed in gemma cups on the thalli of some liverworts such as Marchantia. Mosses reproduce vegetatively by fragmentation and budding of the secondary protonema, not by gemmae in cups.
Q8NEET 2021
Plants follow different pathways in response to environment or phases of life to form different kinds of structures. This ability is called :
Not quite — the answer is C.
The ability of plants to follow different developmental pathways in response to environment or phase of life, as in heterophylly of cotton or buttercup, is called plasticity. Flexibility and elasticity are not the botanical terms used for this.
Q9NEET 2021
Which of the following is an incorrect statement ?
Not quite — the answer is A.
Mature sieve tube elements lose their nucleus and are controlled by the companion cells, so saying they have a conspicuous nucleus is incorrect. Microbodies occur in both plant and animal cells, the perinuclear space separates the two nuclear membranes, and nuclear pores allow two-way traffic of RNA and proteins.
Q10NEET 2021
A typical angiosperm embryo sac at maturity is :
Not quite — the answer is A.
The mature embryo sac has 8 nuclei but only 7 cells: three antipodals, two synergids, one egg cell and one large central cell holding two polar nuclei. The two polar nuclei sharing one cell is why the cell count is one less than the nuclear count.
Q11NEET 2021
The plant hormone used to destroy weeds in a field is :
Not quite — the answer is C.
2,4-D is a synthetic auxin widely used as a herbicide to kill broad-leaved dicot weeds, leaving monocot crops unharmed. IAA and IBA are natural auxins and NAA is used mainly for rooting and preventing fruit drop.
Q12NEET 2021
Which of the following algae produce Carrageen ?
Not quite — the answer is C.
Carrageen is a hydrocolloid obtained commercially from red algae (Rhodophyceae). Brown algae yield algin instead.
Q13NEET 2021
Which of the following stages of meiosis involves division of centromere ?
Not quite — the answer is C.
In meiosis the centromere splits only at anaphase II, letting the sister chromatids move to opposite poles. At anaphase I the homologous chromosomes separate while each centromere stays intact.
Q14NEET 2021
Which of the following plants is monoecious ?
Not quite — the answer is B.
Chara is monoecious: the male globule and the female oogonium develop on the same plant. Papaya, Marchantia polymorpha and Cycas circinalis bear male and female structures on separate plants, so they are dioecious.
Q15NEET 2021
When the centromere is situated in the middle of two equal arms of chromosomes, the chromosome is referred as :
Not quite — the answer is A.
A chromosome whose centromere lies in the middle, giving two equal arms, is metacentric. A sub-metacentric centromere lies slightly away from the middle, giving one shorter and one longer arm.
Q16NEET 2021
Which of the following is not an application of PCR (Polymerase Chain Reaction) ?
Not quite — the answer is C.
PCR amplifies nucleic acid sequences, which is used in molecular diagnosis, gene amplification and detecting gene mutations. It does not act on proteins, so it cannot purify an isolated protein.
Q17NEET 2021
Genera like Selaginella and Salvinia produce two kinds of spores. Such plants are known as :
Not quite — the answer is D.
Selaginella and Salvinia produce two kinds of spores, small microspores and large megaspores, so they are heterosporous. Homosporous plants produce only one kind of spore.
Q18NEET 2021
Complete the flow chart on central dogma. (a) ↻ DNA —(b)→ mRNA —(c)→ (d)
Not quite — the answer is C.
In the central dogma DNA copies itself by replication, is transcribed into mRNA, and mRNA is translated into protein. Transduction is transfer of DNA by viruses and is not a step of the central dogma.
Q19NEET 2021
Which of the following statements is not correct ?
Not quite — the answer is B.
In the sea the standing biomass of phytoplankton is smaller than that of the fishes feeding on them, so the pyramid of biomass is generally inverted, not upright. The pyramid of energy is always upright and the grassland pyramid of numbers is upright, so those statements are correct.
Q20NEET 2021
Which of the following algae contains mannitol as reserve food material ?
Not quite — the answer is A.
Brown algae store food as laminarin or mannitol, and Ectocarpus is a brown alga. Gracilaria is a red alga storing floridean starch, while Volvox and Ulothrix are green algae storing starch.
Q21NEET 2021
During the purification process for recombinant DNA technology, addition of chilled ethanol precipitates out :
Not quite — the answer is B.
After the cell is lysed and RNA, proteins and other molecules are removed with enzymes, adding chilled ethanol makes the purified DNA come out of solution as fine threads. RNA is removed earlier by ribonuclease, not precipitated at this step.
Q22NEET 2021
The factor that leads to Founder effect in a population is :
Not quite — the answer is D.
When a small group breaks away and its allele frequencies change by chance, the new population ends up with a different gene pool; this chance change is genetic drift, and the founder effect is a case of it. Natural selection changes allele frequencies because of fitness differences, not by chance.
Q23NEET 2021
Diadelphous stamens are found in :
Not quite — the answer is C.
In pea the ten stamens form two bundles (nine fused plus one free), so they are diadelphous. China rose has monadelphous stamens (one bundle) and citrus has polyadelphous stamens (many bundles).
Q24NEET 2021
Which of the following are not secondary metabolites in plants ?
Not quite — the answer is B.
Amino acids and glucose are primary metabolites used in basic metabolism like respiration and protein synthesis. Morphine and codeine (alkaloids), vinblastin and curcumin (drugs) and rubber and gums are secondary metabolites.
Q25NEET 2021
Match List - I with List - II. List - I | List - II (a) Cristae | (i) Primary constriction in chromosome (b) Thylakoids | (ii) Disc-shaped sacs in Golgi apparatus (c) Centromere | (iii) Infoldings in mitochondria (d) Cisternae | (iv) Flattened membranous sacs in stroma of plastids Choose the correct answer from the options given below.
Not quite — the answer is C.
Cristae are infoldings of the inner mitochondrial membrane, thylakoids are flattened membranous sacs in the stroma of plastids, the centromere is the primary constriction of a chromosome, and cisternae are the disc-shaped sacs of the Golgi apparatus. Hence (a)-(iii), (b)-(iv), (c)-(i), (d)-(ii).
Q26NEET 2021
When gene targetting involving gene amplification is attempted in an individual's tissue to treat disease, it is known as :
Not quite — the answer is B.
Introducing or targeting genes in a person's cells or tissues to correct a genetic defect and treat disease is gene therapy. Molecular diagnosis only detects a disease, and biopiracy is the unauthorised use of bio-resources.
Q27NEET 2021
The term used for transfer of pollen grains from anthers of one plant to stigma of a different plant which, during pollination, brings genetically different types of pollen grains to stigma, is :
Not quite — the answer is A.
Xenogamy is transfer of pollen from the anther of one plant to the stigma of a different plant, so it brings genetically different pollen. Geitonogamy is transfer between flowers of the same plant and is genetically like self-pollination.
Q28NEET 2021
Which of the following is a correct sequence of steps in a PCR (Polymerase Chain Reaction) ?
Not quite — the answer is A.
Each PCR cycle first denatures the double-stranded DNA by heat, then lets the primers anneal to the single strands, and finally extends the primers using a thermostable DNA polymerase. Extension cannot come before annealing because the polymerase needs a primer to start.
Q29NEET 2021
The first stable product of CO₂ fixation in sorghum is :
Not quite — the answer is B.
Sorghum is a C₄ plant, and in C₄ plants PEP carboxylase fixes CO₂ into the four-carbon oxaloacetic acid as the first stable product. Phosphoglyceric acid is the first stable product only in C₃ plants.
Q30NEET 2021
Which of the following statements is incorrect ?
Not quite — the answer is D.
Cyclic photophosphorylation uses only PS I, with electrons cycling back to it so that only ATP is made, so the statement that it involves both photosystems is incorrect. Non-cyclic photophosphorylation makes both ATP and NADPH + H⁺, and stroma lamellae carry only PS I and lack NADP reductase.
Q31NEET 2021
Identify the correct statement.
Not quite — the answer is B.
In bacteria, RNA polymerase associates transiently with the rho factor to terminate transcription. Capping adds methyl guanosine triphosphate to the 5′ end, the template strand (not the coding strand) is copied, and split genes are typical of eukaryotes.
Q32NEET 2021
In the exponential growth equation Nt = N₀eʳᵗ, e represents :
Not quite — the answer is C.
In the exponential growth equation Nt = N₀eʳᵗ, e is the base of natural logarithms, about 2.71828. The other phrases are not standard names of a logarithm base.
Q33NEET 2021
What is the role of RNA polymerase III in the process of transcription in eukaryotes ?
Not quite — the answer is B.
In eukaryotes RNA polymerase III transcribes tRNA, 5S rRNA and snRNAs. RNA polymerase I makes the 28S, 18S and 5.8S rRNAs and RNA polymerase II makes hnRNA, the precursor of mRNA.
Q34NEET 2021
Plasmid pBR322 has PstI restriction enzyme site within gene ampᴿ that confers ampicillin resistance. If this enzyme is used for inserting a gene for β-galactoside production and the recombinant plasmid is inserted in an E.coli strain
Not quite — the answer is A.
PstI cuts inside the ampicillin resistance gene, so inserting a foreign gene there disrupts it by insertional inactivation and the recombinant plasmid can no longer make the host resistant to ampicillin. The transformed cells therefore cannot both resist ampicillin and express the new gene.
Q35NEET 2021
Match List - I with List - II. List - I | List - II (a) S phase | (i) Proteins are synthesized (b) G₂ phase | (ii) Inactive phase (c) Quiescent stage | (iii) Interval between mitosis and initiation of DNA replication (d) G₁ phase | (iv) DNA replication Choose the correct answer from the options given below.
Not quite — the answer is C.
S phase is when DNA replicates, G₂ is when proteins needed for mitosis are made, the quiescent stage (G₀) is an inactive phase, and G₁ is the interval between mitosis and the start of DNA replication. Hence (a)-(iv), (b)-(i), (c)-(ii), (d)-(iii).
Q36NEET 2021
Which of the following statements is correct ?
Not quite — the answer is B.
Fusion of the protoplasm of two motile or non-motile gametes is plasmogamy, which is correct. Fusion of two nuclei (not two cells) is karyogamy, organisms on dead matter are saprophytes, and nitrogen-fixing cells of cyanobacteria are heterocysts, not sheath cells.
Q37NEET 2021
Which of the following statements is incorrect ?
Not quite — the answer is B.
In the electron transport chain one NADH + H⁺ yields 3 ATP and one FADH₂ yields 2 ATP, so the statement has the numbers swapped and is incorrect. Oxygen acts only at the end as the final electron acceptor, and ATP is made by complex V (ATP synthase) using the proton gradient.
Q38NEET 2021
In some members of which of the following pairs of families, pollen grains retain their viability for months after release ?
Not quite — the answer is D.
Pollen of some members of Rosaceae, Leguminosae and Solanaceae stays viable for months. In Poaceae such as rice and wheat pollen loses viability within about 30 minutes, so any pair containing Poaceae is wrong.
Q39NEET 2021
DNA fingerprinting involves identifying differences in some specific regions in DNA sequence, called as :
Not quite — the answer is B.
DNA fingerprinting looks for differences in regions of repetitive DNA, where short stretches are repeated many times and the number of repeats differs between people. Satellite DNA is one type of repetitive DNA, so repetitive DNA is the broader, textbook answer.
Q40NEET 2021
Match List - I with List - II. List - I | List - II (a) Protein | (i) C = C double bonds (b) Unsaturated fatty acid | (ii) Phosphodiester bonds (c) Nucleic acid | (iii) Glycosidic bonds (d) Polysaccharide | (iv) Peptide bonds Choose the correct answer from the options given below.
Not quite — the answer is A.
Amino acids in proteins are linked by peptide bonds, unsaturated fatty acids have C = C double bonds, nucleotides in nucleic acids are joined by phosphodiester bonds, and sugars in polysaccharides by glycosidic bonds. Hence (a)-(iv), (b)-(i), (c)-(ii), (d)-(iii).
Q41NEET 2021
Which one of the following organisms bears hollow and pneumatic long bones ?
Not quite — the answer is A.
Hollow, air-filled (pneumatic) long bones are a feature of birds, and Neophron is a bird (vulture). Hemidactylus is a lizard, while Macropus (kangaroo) and Ornithorhynchus (platypus) are mammals with solid bones.
Q42NEET 2021
Chronic auto immune disorder affecting neuro muscular junction leading to fatigue, weakening and paralysis of skeletal muscle is called as :
Not quite — the answer is C.
Myasthenia gravis is an autoimmune disorder of the neuromuscular junction causing fatigue, weakening and paralysis of skeletal muscle. Muscular dystrophy is a genetic degeneration of muscle, and arthritis and gout affect joints.
Q43NEET 2021
Which one of the following is an example of Hormone releasing IUD ?
Not quite — the answer is B.
LNG-20 releases a progestogen (levonorgestrel), so it is a hormone-releasing IUD like Progestasert. CuT, Cu7 and Multiload 375 are copper-releasing IUDs.
Q44NEET 2021
Select the favourable conditions required for the formation of oxyhaemoglobin at the alveoli.
Not quite — the answer is A.
At the alveoli, high pO₂, low pCO₂, fewer H⁺ ions (higher pH) and lower temperature all favour binding of oxygen to haemoglobin. The opposite set of conditions, found in tissues, favours release of oxygen.
Q45NEET 2021
The organelles that are included in the endomembrane system are :
Not quite — the answer is B.
The endomembrane system is the group of organelles that work in coordination: endoplasmic reticulum, Golgi complex, lysosomes and vacuoles. Mitochondria, chloroplasts and peroxisomes are not part of it, and ribosomes have no membrane.
Q46NEET 2021
Match List - I with List - II. List - I | List - II (a) Metamerism | (i) Coelenterata (b) Canal system | (ii) Ctenophora (c) Comb plates | (iii) Annelida (d) Cnidoblasts | (iv) Porifera Choose the correct answer from the options given below.
Not quite — the answer is C.
Metamerism is typical of Annelida, the canal system of Porifera, comb plates of Ctenophora, and cnidoblasts of Coelenterata. Hence (a)-(iii), (b)-(iv), (c)-(ii), (d)-(i).
Q47NEET 2021
A specific recognition sequence identified by endonucleases to make cuts at specific positions within the DNA is :
Not quite — the answer is C.
Restriction endonucleases recognise palindromic nucleotide sequences, which read the same on both strands in the 5′→3′ direction, and cut at specific positions within them. Okazaki fragments and poly-A tails are unrelated to restriction sites.
Q48NEET 2021
Which of the following RNAs is not required for the synthesis of protein ?
Not quite — the answer is D.
mRNA carries the code, tRNA brings amino acids and rRNA forms the ribosome, so all three are needed to make protein. siRNA works in RNA interference to silence genes, not in protein synthesis.
Q49NEET 2021
The partial pressures (in mm Hg) of oxygen (O₂) and carbon dioxide (CO₂) at alveoli (the site of diffusion) are :
Not quite — the answer is A.
Alveolar air has pO₂ of 104 mm Hg and pCO₂ of 40 mm Hg. The values 159 and 0.3 are for atmospheric air, and 40 and 45 are for deoxygenated blood.
Q50NEET 2021
Which of the following statements wrongly represents the nature of smooth muscle ?
Not quite — the answer is C.
Intercalated discs are found in cardiac muscle, where they let the cells contract as a unit, so attributing them to smooth muscle is wrong. Smooth muscle is non-striated, involuntary and found in the walls of blood vessels and other hollow organs.
Q51NEET 2021
Match the following : List - I | List - II (a) Physalia | (i) Pearl oyster (b) Limulus | (ii) Portuguese Man of War (c) Ancylostoma | (iii) Living fossil (d) Pinctada | (iv) Hookworm Choose the correct answer from the options given below.
Not quite — the answer is C.
Physalia is the Portuguese man of war, Limulus (king crab) is a living fossil, Ancylostoma is the hookworm, and Pinctada is the pearl oyster. Hence (a)-(ii), (b)-(iii), (c)-(iv), (d)-(i).
Q52NEET 2021
Veneral diseases can spread through : (a) Using sterile needles (b) Transfusion of blood from infected person (c) Infected mother to foetus (d) Kissing (e) Inheritance Choose the correct answer from the options given below.
Not quite — the answer is C.
Sexually transmitted infections can spread through transfusion of infected blood and from an infected mother to the foetus. Sterile needles carry no infection, and kissing and inheritance are not routes of spread, so only (b) and (c) apply.
Q53NEET 2021
With regard to insulin choose correct options. (a) C-peptide is not present in mature insulin. (b) The insulin produced by rDNA technology has C-peptide. (c) The pro-insulin has C-peptide. (d) A-peptide and B-peptide of insulin are interconnected by disulphide bridges. Choose the correct answer from the options given below.
Not quite — the answer is C.
Pro-insulin carries an extra C-peptide that is removed to give mature insulin, whose A and B chains are joined by disulphide bridges. Eli Lilly's rDNA insulin was made by producing the A and B chains separately and joining them, so it has no C-peptide; hence (a), (c) and (d).
Q54NEET 2021
The fruit fly has 8 chromosomes (2n) in each cell. During interphase of Mitosis if the number of chromosomes at G₁ phase is 8, what would be the number of chromosomes after S phase ?
Not quite — the answer is A.
In S phase the DNA content doubles but the chromosome number does not change, because each chromosome simply comes to have two sister chromatids. So a cell with 8 chromosomes in G₁ still has 8 after S phase; 16 is the count of chromatids, not chromosomes.
Q55NEET 2021
Which is the "Only enzyme" that has "Capability" to catalyse Initiation, Elongation and Termination in the process of transcription in prokaryotes ?
Not quite — the answer is B.
In bacteria a single DNA-dependent RNA polymerase catalyses initiation (with the sigma factor), elongation and termination (with the rho factor) of transcription. DNA-dependent DNA polymerase acts in replication, not transcription.
Q56NEET 2021
In a cross between a male and female, both heterozygous for sickle cell anaemia gene, what percentage of the progeny will be diseased ?
Not quite — the answer is C.
Sickle cell anaemia is autosomal recessive, so Hbᴬ Hbˢ × Hbᴬ Hbˢ gives 1 Hbᴬ Hbᴬ : 2 Hbᴬ Hbˢ : 1 Hbˢ Hbˢ. Only the Hbˢ Hbˢ quarter is diseased, i.e. 25%; the 50% heterozygotes are carriers, not patients.
Q57NEET 2021
Which stage of meiotic prophase shows terminalisation of chiasmata as its distinctive feature ?
Not quite — the answer is C.
Terminalisation of chiasmata, the movement of chiasmata toward the chromosome ends, is the distinctive feature of diakinesis, the last stage of prophase I. Crossing over takes place in pachytene and synapsis in zygotene.
Q58NEET 2021
Read the following statements. (a) Metagenesis is observed in Helminths. (b) Echinoderms are triploblastic and coelomate animals. (c) Round worms have organ-system level of body organization. (d) Comb plates present in ctenophores help in digestion. (e) Water vascular system is characteristic of Echinoderms. Choose the correct answer from the options given below.
Not quite — the answer is D.
Echinoderms are triploblastic coelomates, roundworms have organ-system level organisation, and the water vascular system is characteristic of echinoderms, so (b), (c) and (e) are correct. Metagenesis occurs in cnidarians, not helminths, and comb plates of ctenophores help in locomotion, not digestion.
Q59NEET 2021
During the process of gene amplification using PCR, if very high temperature is not maintained in the beginning, then which of the following steps of PCR will be affected first ?
Not quite — the answer is C.
The first step of PCR, denaturation, needs a very high temperature (about 94 °C) to separate the two DNA strands, so it is affected first if that temperature is not reached. Ligation is not a PCR step at all.
Q60NEET 2021
Identify the incorrect pair.
Not quite — the answer is D.
Ricin, like abrin, is a toxin, so pairing it with drugs is incorrect. Codeine is an alkaloid, abrin a toxin and concanavalin A a lectin, so those pairs are correct.
Q61NEET 2021
Persons with 'AB' blood group are called as "Universal recipients". This is due to :
Not quite — the answer is D.
People with AB blood have both A and B antigens on their RBCs and therefore make neither anti-A nor anti-B antibodies in plasma, so donor RBCs of any group are not attacked. The antigens are present, not absent, on their RBCs.
Q62NEET 2021
Which one of the following belongs to the family Muscidae ?
Not quite — the answer is D.
The housefly, Musca domestica, belongs to the family Muscidae of order Diptera. Grasshopper and cockroach belong to other insect orders and the firefly is a beetle.
Q63NEET 2021
The centriole undergoes duplication during :
Not quite — the answer is A.
In animal cells, as DNA replicates in the nucleus during S phase, the centriole duplicates in the cytoplasm. By prophase the duplicated centrioles are already moving to the poles.
Q64NEET 2021
Receptors for sperm binding in mammals are present on :
Not quite — the answer is D.
The sperm binds to receptors on the zona pellucida of the ovum, and this binding sets off changes in the zona that block entry of more sperm. The corona radiata is the outer cell layer that the sperm must pass through first.
Q65NEET 2021
Which enzyme is responsible for the conversion of inactive fibrinogens to fibrins ?
Not quite — the answer is A.
Thrombin converts soluble inactive fibrinogen into fibrin threads that form the clot. Thrombokinase acts one step earlier, converting prothrombin into thrombin.
Q66NEET 2021
Match List - I with List - II. List - I | List - II (a) Aspergillus niger | (i) Acetic Acid (b) Acetobacter aceti | (ii) Lactic Acid (c) Clostridium butylicum | (iii) Citric Acid (d) Lactobacillus | (iv) Butyric Acid Choose the correct answer from the options given below.
Not quite — the answer is A.
Aspergillus niger produces citric acid, Acetobacter aceti acetic acid, Clostridium butylicum butyric acid, and Lactobacillus lactic acid. Hence (a)-(iii), (b)-(i), (c)-(iv), (d)-(ii).
Q67NEET 2021
Erythropoietin hormone which stimulates R.B.C. formation is produced by :
Not quite — the answer is D.
The juxtaglomerular cells of the kidney produce erythropoietin, which stimulates RBC formation in the bone marrow. The bone marrow is where RBCs are made, not where the hormone is produced.
Q68NEET 2021
Match List - I with List - II. List - I | List - II (a) Vaults | (i) Entry of sperm through Cervix is blocked (b) IUDs | (ii) Removal of Vas deferens (c) Vasectomy | (iii) Phagocytosis of sperms within the Uterus (d) Tubectomy | (iv) Removal of fallopian tube Choose the correct answer from the options given below.
Not quite — the answer is B.
Vaults are barriers that block sperm entry through the cervix, IUDs increase phagocytosis of sperms in the uterus, vasectomy removes a part of the vas deferens, and tubectomy removes a part of the fallopian tube. Hence (a)-(i), (b)-(iii), (c)-(ii), (d)-(iv).
Q69NEET 2021
If Adenine makes 30% of the DNA molecule, what will be the percentage of Thymine, Guanine and Cytosine in it ?
Not quite — the answer is C.
By Chargaff's rule A = T and G = C, so if A is 30% then T is also 30%. The remaining 40% is shared equally, giving G = 20% and C = 20%.
Q70NEET 2021
Identify the types of cell junctions that help to stop the leakage of the substances across a tissue and facilitation of communication with neighbouring cells via rapid transfer of ions and molecules.
Not quite — the answer is B.
Tight junctions seal neighbouring cells together and stop substances leaking across a tissue, while gap junctions connect the cytoplasm of adjoining cells for rapid transfer of ions and small molecules. Adhering junctions only cement cells together.
Q71NEET 2021
Which one of the following statements about Histones is wrong ?
Not quite — the answer is B.
Histones are rich in the basic amino acids lysine and arginine, so they carry positive side-chain charges and are basic, not slightly acidic. Eight histone molecules form the histone octamer of the nucleosome.
Q72NEET 2021
Which of these is not an important component of initiation of parturition in humans ?
Not quite — the answer is D.
Parturition is triggered by foetal and placental signals that raise the estrogen to progesterone ratio, release oxytocin and cause prostaglandin synthesis, producing strong uterine contractions. Prolactin acts on milk production and is not part of the trigger for birth.
Q73NEET 2021
Match List - I with List - II. List - I | List - II (a) Filariasis | (i) Haemophilus influenzae (b) Amoebiasis | (ii) Trichophyton (c) Pneumonia | (iii) Wuchereria bancrofti (d) Ringworm | (iv) Entamoeba histolytica Choose the correct answer from the options given below.
Not quite — the answer is B.
Filariasis is caused by Wuchereria bancrofti, amoebiasis by Entamoeba histolytica, pneumonia by Haemophilus influenzae (and Streptococcus pneumoniae), and ringworm by Trichophyton. Hence (a)-(iii), (b)-(iv), (c)-(i), (d)-(ii).
Q74NEET 2021
Statement I : The codon 'AUG' codes for methionine and phenylalanine. Statement II : 'AAA' and 'AAG' both codons code for the amino acid lysine. In the light of the above statements, choose the correct answer from the options given below.
Not quite — the answer is D.
AUG codes only for methionine (it is also the start codon); phenylalanine is coded by UUU and UUC, so Statement I is false. AAA and AAG both code for lysine, showing degeneracy of the code, so Statement II is true.
Q75NEET 2021
Match List - I with List - II. List - I | List - II (a) Scapula | (i) Cartilaginous joints (b) Cranium | (ii) Flat bone (c) Sternum | (iii) Fibrous joints (d) Vertebral column | (iv) Triangular flat bone Choose the correct answer from the options given below.
Not quite — the answer is D.
The scapula is a large triangular flat bone, the cranial bones are joined by fibrous (immovable) joints, the sternum is a flat bone, and vertebrae are joined by cartilaginous joints. Hence (a)-(iv), (b)-(iii), (c)-(ii), (d)-(i).
Q76NEET 2021
The Adenosine deaminase deficiency results into :
Not quite — the answer is A.
Adenosine deaminase is needed for the immune system to work, and its deficiency causes severe combined immunodeficiency; it was the first disease treated by gene therapy. Parkinson's and Addison's diseases have no link with this enzyme.
Q77NEET 2021
Match List - I with List - II. List - I | List - II (a) Adaptive radiation | (i) Selection of resistant varieties due to excessive use of herbicides and pesticides (b) Convergent evolution | (ii) Bones of forelimbs in Man and Whale (c) Divergent evolution | (iii) Wings of Butterfly and Bird (d) Evolution by anthropogenic action | (iv) Darwin Finches Choose the correct answer from the options given below.
Not quite — the answer is A.
Darwin's finches show adaptive radiation, wings of butterfly and bird are analogous organs showing convergent evolution, forelimbs of man and whale are homologous organs showing divergent evolution, and resistance after heavy herbicide and pesticide use is evolution by anthropogenic action. Hence (a)-(iv), (b)-(iii), (c)-(ii), (d)-(i).
Q78NEET 2021
Following are the statements with reference to 'lipids'. (a) Lipids having only single bonds are called unsaturated fatty acids. (b) Lecithin is a phospholipid. (c) Trihydroxy propane is glycerol. (d) Palmitic acid has 20 carbon atoms including carboxyl carbon. (e) Arachidonic acid has 16 carbon atoms. Choose the correct answer from the options given below.
Not quite — the answer is C.
Lecithin is a phospholipid and glycerol is trihydroxy propane, so (b) and (c) are true. Fatty acids with only single bonds are saturated, palmitic acid has 16 carbons and arachidonic acid has 20, so (a), (d) and (e) are false.
Q79NEET 2021
During muscular contraction which of the following events occur ? (a) 'H' zone disappears (b) 'A' band widens (c) 'I' band reduces in width (d) Myosine hydrolyzes ATP, releasing the ADP and Pi (e) Z-lines attached to actins are pulled inwards Choose the correct answer from the options given below.
Not quite — the answer is A.
During contraction myosin heads hydrolyse ATP, releasing ADP and Pi, and pull the actin filaments so the Z-lines move inward, the I band shortens and the H zone disappears; so (a), (c), (d) and (e) occur. The A band keeps its length, so its widening does not occur.
Biology: not in the current NEET syllabus
These 17 questions are from topics NCERT dropped in its 2023 revision. Shown for completeness; you can skip them for NEET 2027.
17 questions. Tap an option to check your answer.
Q1NEET 2021
Match List - I with List - II. List - I | List - II (a) Lenticels | (i) Phellogen (b) Cork cambium | (ii) Suberin deposition (c) Secondary cortex | (iii) Exchange of gases (d) Cork | (iv) Phelloderm Choose the correct answer from the options given below.
Not quite — the answer is B.
Lenticels are openings in the bark for gaseous exchange, cork cambium is phellogen, secondary cortex is phelloderm, and cork cells have suberin deposited in their walls. Hence (a)-(iii), (b)-(i), (c)-(iv), (d)-(ii).
Q2NEET 2021
The site of perception of light in plants during photoperiodism is :
Not quite — the answer is D.
The photoperiodic stimulus is perceived by the leaves, which then send a signal to the shoot apex where flowers form. The shoot apex is where flowering happens, not where light duration is sensed.
Q3NEET 2021
The amount of nutrients, such as carbon, nitrogen, phosphorus and calcium present in the soil at any given time, is referred as :
Not quite — the answer is C.
The amount of nutrients such as carbon, nitrogen, phosphorus and calcium present in the soil at a given time is the standing state. Standing crop is the mass of living material present at each trophic level, not soil nutrients.
Q4NEET 2021
Select the correct pair.
Not quite — the answer is C.
Medullary ray cells lying next to the intrafascicular cambium become meristematic and form the interfascicular cambium, completing the cambial ring. Large empty colourless cells of grass epidermis are bulliform cells, the thick-walled cells around dicot leaf bundles form the bundle sheath, and loose cells forming the lens-shaped bark opening are complementary cells of a lenticel.
Q5NEET 2021 · Q113
Mutations in plant cells can be induced by :
Not quite — the answer is C.
Mutations in plants can be induced by chemicals or by radiation such as gamma rays, which is used in mutation breeding. Kinetin and zeatin are cytokinins, not mutagens, and infrared rays are not used for this.
Q6NEET 2021 · Q114
Match List - I with List - II. List - I | List - II (a) Protoplast fusion | (i) Totipotency (b) Plant tissue culture | (ii) Pomato (c) Meristem culture | (iii) Somaclones (d) Micropropagation | (iv) Virus free plants Choose the correct answer from the options given below.
Not quite — the answer is B.
Protoplast fusion of potato and tomato gave the pomato, plant tissue culture relies on totipotency, meristem culture gives virus-free plants, and micropropagation produces genetically identical somaclones. Hence (a)-(ii), (b)-(i), (c)-(iv), (d)-(iii).
Q7NEET 2021
Which of the following characteristics is incorrect with respect to cockroach ?
Not quite — the answer is A.
In cockroach a ring of 6–8 gastric caeca lies at the junction of the foregut and midgut, not midgut and hindgut, so that statement is incorrect. The junction of midgut and hindgut carries the Malpighian tubules instead.
Q8NEET 2021 · Q127
Match List - I with List - II. List - I | List - II (a) Cohesion | (i) More attraction in liquid phase (b) Adhesion | (ii) Mutual attraction among water molecules (c) Surface tension | (iii) Water loss in liquid phase (d) Guttation | (iv) Attraction towards polar surfaces Choose the correct answer from the options given below.
Not quite — the answer is A.
Cohesion is the mutual attraction among water molecules, adhesion is attraction of water to polar surfaces, surface tension arises because water molecules are attracted more to each other in the liquid phase than to the gas phase, and guttation is loss of water in liquid form. Hence (a)-(ii), (b)-(iv), (c)-(i), (d)-(iii).
Q9NEET 2021 · Q147
Match Column - I with Column - II. Column - I | Column - II (a) Nitrococcus | (i) Denitrification (b) Rhizobium | (ii) Conversion of ammonia to nitrite (c) Thiobacillus | (iii) Conversion of nitrite to nitrate (d) Nitrobacter | (iv) Conversion of atmospheric nitrogen to ammonia Choose the correct answer from options given below.
Not quite — the answer is A.
Nitrococcus oxidises ammonia to nitrite, Rhizobium fixes atmospheric nitrogen into ammonia, Thiobacillus carries out denitrification, and Nitrobacter oxidises nitrite to nitrate. Hence (a)-(ii), (b)-(iv), (c)-(i), (d)-(iii).
Q10NEET 2021
Match List - I with List - II. List - I | List - II (a) Allen's Rule | (i) Kangaroo rat (b) Physiological adaptation | (ii) Desert lizard (c) Behavioural adaptation | (iii) Marine fish at depth (d) Biochemical adaptation | (iv) Polar seal Choose the correct answer from the options given below.
Not quite — the answer is C.
Polar seals with short limbs illustrate Allen's rule, the kangaroo rat's water conservation is a physiological adaptation, the desert lizard's basking and burrowing is behavioural, and deep-sea fish with special enzymes show biochemical adaptation. Hence (a)-(iv), (b)-(i), (c)-(ii), (d)-(iii).
Q11NEET 2021 · Q156
Sphincter of oddi is present at :
Not quite — the answer is B.
The sphincter of Oddi guards the opening of the common hepato-pancreatic duct into the duodenum. The ileo-caecal junction has the ileo-caecal valve and the gastro-oesophageal junction the cardiac sphincter.
Q12NEET 2021
Assertion (A) : A person goes to high altitude and experiences 'altitude sickness' with symptoms like breathing difficulty and heart palpitations. Reason (R) : Due to low atmospheric pressure at high altitude, the body does not get sufficient oxygen. In the light of the above statements, choose the correct answer from the options given below.
Not quite — the answer is A.
At high altitude the low atmospheric pressure means less oxygen enters the body, which causes altitude sickness with breathlessness and palpitations. So both the Assertion and the Reason are true, and the Reason explains the Assertion.
Q13NEET 2021
Following are the statements about prostomium of earthworm. (a) It serves as a covering for mouth. (b) It helps to open cracks in the soil into which it can crawl. (c) It is one of the sensory structures. (d) It is the first body segment. Choose the correct answer from the options given below.
Not quite — the answer is A.
The prostomium is a lobe that covers the mouth, works as a wedge to open cracks in the soil, and is sensory, so (a), (b) and (c) are correct. It is not the first body segment; the first segment is the peristomium, which bears the mouth.
Q14NEET 2021 · Q164
Succus entericus is referred to as :
Not quite — the answer is B.
Succus entericus is the intestinal juice, formed by secretions of the brush border cells and goblet cells of the small intestine. Chyme is the acidic food mass leaving the stomach, not a secretion.
Q15NEET 2021 · Q165
Which of the following is not an objective of Biofortification in crops ?
Not quite — the answer is B.
Biofortification aims to raise nutritional quality: protein content and quality, oil quality, vitamin content and micronutrient and mineral content. Disease resistance is a goal of plant breeding in general, not of biofortification.
Q16NEET 2021 · Q174
Dobson units are used to measure thickness of :
Not quite — the answer is C.
The thickness of the ozone layer, from ground to top of the atmosphere, is measured in Dobson units. CFCs are the chemicals that deplete ozone, not what Dobson units measure.
Q17NEET 2021 · Q192
Which of the following is not a step in Multiple Ovulation Embryo Transfer Technology (MOET) ?
Not quite — the answer is A.
In MOET the cow is given a hormone with FSH-like activity, not LH-like activity, to induce superovulation, so that step is wrong. The cow then yields 6–8 eggs, is mated or artificially inseminated, and embryos at the 8–32 cell stage are transferred to surrogate mothers.
Chapter-wise split of NEET 2021 Biology
- Molecular Basis of Inheritance9 Q
- Biotechnology: Principles and Processes6 Q
- Plant Kingdom5 Q
- Cell Cycle and Cell Division5 Q
- Cell: The Unit of Life4 Q
- Biotechnology and Its Applications4 Q
- Biomolecules4 Q
- Animal Kingdom4 Q
- Organisms and Populations3 Q
- Sexual Reproduction in Flowering Plants3 Q
- Locomotion and Movement3 Q
- Reproductive Health3 Q
- Ecosystem2 Q
- Principles of Inheritance and Variation2 Q
- Plant Growth and Development2 Q
- Evolution2 Q
- Photosynthesis in Higher Plants2 Q
- Breathing and Exchange of Gases2 Q
- Structural Organisation in Animals2 Q
- Body Fluids and Circulation2 Q
- Human Reproduction2 Q
- Anatomy of Flowering Plants1 Q
- Morphology of Flowering Plants1 Q
- Biological Classification1 Q
- Respiration in Plants1 Q
- The Living World1 Q
- Microbes in Human Welfare1 Q
- Chemical Coordination and Integration1 Q
- Human Health and Disease1 Q
About this paper
How many questions from NEET 2021 are on this page?
173 questions (Physics 35, Chemistry 42, Biology 96). Questions that need a diagram we could not reproduce, or whose wording in the source was unclear, are left out.
Are these the original questions?
Yes. The questions and options are as set in the NEET 2021 paper, conducted by NTA. The answer to every question was checked by the RankUp team, and the explanations are RankUp's own.
Is NEET 2021 useful for NEET 2027?
Yes. The NEET syllabus is built on the same NCERT books. 27 questions here are on topics NCERT has since dropped; they are listed separately so you can skip them.
More NEET and AIPMT papers
Practise thousands more questions chapter-wise in the RankUp app.
- NEET 2020
- NEET 2019
- NEET 2018
- NEET 2017
- NEET 2017 (Gujarati paper)
- NEET 2016 Phase 2
- NEET 2016 Phase 1
- AIPMT 2015
- AIPMT 2014
- NEET 2013
- AIPMT 2012 Mains
- AIPMT 2012 Prelims
- AIPMT 2011 Mains
- AIPMT 2011 Prelims
- AIPMT 2010 Mains
- AIPMT 2010 Prelims
- AIPMT 2009 Prelims
- AIPMT 2008 Prelims
- AIPMT 2007 Prelims
- AIPMT 2006 Prelims
- AIPMT 2005 Prelims
- All NEET PYQs
