AIPMT 2012 Prelims Question PaperPhysics, Chemistry and Biology, with checked answers and solutions
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171 questions from the AIPMT 2012 Prelims paper, conducted by CBSE. 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.
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AIPMT 2012 Prelims Physics questions
37 questions. Tap an option to check your answer.
Q1AIPMT 2012 Prelims
In a CE transistor amplifier, the audio signal voltage across the collector resistance of 2 kΩ is 2 V. If the base resistance is 1 kΩ and the current amplification of the transistor is 100, the input signal voltage is
Not quite — the answer is A.
Voltage gain of a CE amplifier = β(R_C/R_B) = 100 × (2 kΩ/1 kΩ) = 200. Input voltage = output/gain = 2 V/200 = 0.01 V = 10 mV. Taking 0.1 V comes from using only the resistance ratio or only β instead of their product.
Q2AIPMT 2012 Prelims
A coil of resistance 400 Ω is placed in a magnetic field. If the magnetic flux φ (Wb) linked with the coil varies with time t (s) as φ = 50t² + 4, the current in the coil at t = 2 s is
Not quite — the answer is B.
Induced emf e = dφ/dt = 100t, which is 200 V at t = 2 s. Current = e/R = 200/400 = 0.5 A. The constant 4 in φ does not contribute to the emf.
Q3AIPMT 2012 Prelims
A solid cylinder of mass 3 kg is rolling on a horizontal surface with velocity 4 m s⁻¹. It collides with a horizontal spring of force constant 200 N m⁻¹. The maximum compression produced in the spring will be
Not quite — the answer is C.
A rolling solid cylinder has KE = ½mv² + ½(½mR²)(v/R)² = ¾mv² = ¾ × 3 × 16 = 36 J. Setting ½kx² = 36 gives x² = 72/200 = 0.36, so x = 0.6 m. Ignoring rotational KE gives 24 J and x ≈ 0.49 m, which leads to the 0.5 m trap.
Q4AIPMT 2012 Prelims
An electric dipole of moment p is placed in an electric field of intensity E. The dipole acquires a position such that the axis of the dipole makes an angle θ with the direction of the field. Assuming that the potential energy of the dipole to be zero when θ = 90°, the torque and the potential energy of the dipole will respectively be
Not quite — the answer is B.
Torque on a dipole is τ = pE sin θ, and with U taken as zero at θ = 90°, the potential energy is U = −pE cos θ. The forms with 2pE cos θ wrongly double the energy, and pE cos θ is not the torque.
Q5AIPMT 2012 Prelims
The horizontal range and the maximum height of a projectile are equal. The angle of projection of the projectile is
Not quite — the answer is C.
Range R = u² sin 2θ/g = 2u² sin θ cos θ/g and maximum height H = u² sin²θ/(2g). Setting R = H gives 2 cos θ = sin θ/2, i.e. tan θ = 4, so θ = tan⁻¹ 4. An angle of 45° gives maximum range, not R = H.
Q6AIPMT 2012 Prelims
If the nuclear radius of ²⁷Al is 3.6 fermi, the approximate nuclear radius of ⁶⁴Cu in fermi is
Not quite — the answer is D.
Nuclear radius R ∝ A^(1/3), so R_Cu = 3.6 × (64/27)^(1/3) = 3.6 × 4/3 = 4.8 fermi. A heavier nucleus must have a larger radius, which rules out the smaller values.
Q7AIPMT 2012 Prelims
Two similar coils of radius R are lying concentrically with their planes at right angles to each other. The currents flowing in them are I and 2I, respectively. The resultant magnetic field induction at the centre will be
Not quite — the answer is B.
The coils give fields μ₀I/(2R) and μ₀(2I)/(2R) = μ₀I/R at the centre, and these are perpendicular because the coil planes are perpendicular. Resultant B = √[(μ₀I/2R)² + (μ₀I/R)²] = √5 μ₀I/(2R). Simply adding them (3μ₀I/2R) ignores that the fields are at right angles.
Q8AIPMT 2012 Prelims
When a biconvex lens of glass having refractive index 1.47 is dipped in a liquid, it acts as a plane sheet of glass. This implies that the liquid must have refractive index
Not quite — the answer is B.
By the lens maker's formula 1/f = (μ_g/μ_l − 1)(1/R₁ − 1/R₂). The lens behaves like a plane sheet (no power) only when μ_g/μ_l = 1, i.e. the liquid has the same refractive index as glass, 1.47. A liquid of smaller index would leave it a converging lens.
Q9AIPMT 2012 Prelims
A particle has initial velocity (2î + 3ĵ) and acceleration (0.3î + 0.2ĵ). The magnitude of velocity after 10 seconds will be
Not quite — the answer is C.
v = u + at = (2 + 0.3 × 10)î + (3 + 0.2 × 10)ĵ = 5î + 5ĵ. Magnitude = √(25 + 25) = 5√2 units. Adding the components as scalars (5 + 5 or 9) is the trap.
Q10AIPMT 2012 Prelims
The height at which the weight of a body becomes 1/16th of its weight on the surface of earth (radius R) is
Not quite — the answer is D.
g_h = g/(1 + h/R)². For g_h = g/16, 1 + h/R = 4, so h = 3R. 4R is the distance from the centre of the earth, not the height above the surface.
Q11AIPMT 2012 Prelims
Four point charges −Q, −q, 2q and 2Q are placed, one at each corner of a square. The relation between Q and q for which the potential at the centre of the square is zero is
Not quite — the answer is B.
All four charges are at the same distance from the centre, so the potential is proportional to the sum of charges: −Q − q + 2q + 2Q = Q + q. For zero potential, Q = −q. Q = q would make the sum 2q, not zero.
Q12AIPMT 2012 Prelims
When a string is divided into three segments of length l₁, l₂ and l₃, the fundamental frequencies of these three segments are ν₁, ν₂ and ν₃ respectively. The original fundamental frequency (ν) of the string is
Not quite — the answer is D.
For the same string (same tension and linear density) the fundamental frequency ν = v/(2l) is inversely proportional to length. Since l = l₁ + l₂ + l₃, 1/ν = 1/ν₁ + 1/ν₂ + 1/ν₃. Adding frequencies directly would wrongly treat ν as proportional to length.
Q13AIPMT 2012 Prelims
A ring is made of a wire having a resistance R₀ = 12 Ω. Points A and B on the ring divide it into two arcs of lengths l₁ and l₂. At which points A and B should a current carrying conductor be connected so that the resistance R of the sub circuit between these points is equal to 8/3 Ω?
Not quite — the answer is A.
The two arcs have resistances R₁ and R₂ with R₁ + R₂ = 12 Ω, and they are in parallel between A and B: R₁R₂/12 = 8/3, so R₁R₂ = 32. Then R₁ = 4 Ω and R₂ = 8 Ω, and since resistance is proportional to length, l₁/l₂ = 1/2.
Q14AIPMT 2012 Prelims
A geostationary satellite is orbiting the earth at a height of 5R above the surface of the earth, R being the radius of the earth. The time period of another satellite in hours at a height of 2R from the surface of the earth is
Not quite — the answer is D.
Orbit radii are 6R (geostationary, T = 24 h) and 3R (height 2R). By Kepler's law T ∝ r^(3/2): T = 24 × (3R/6R)^(3/2) = 24/(2√2) = 6√2 h. Using heights (5R and 2R) instead of orbital radii gives a wrong value.
Q15AIPMT 2012 Prelims
If the radius of a star is R and it acts as a black body, what would be the temperature of the star, in which the rate of energy production is Q? (σ stands for Stefan's constant)
Not quite — the answer is A.
For a black body, power radiated = σT⁴ × area = 4πR²σT⁴. In steady state this equals the energy production rate Q, so T = (Q/(4πR²σ))^(1/4). The expression without the fourth root gives T⁴, not T.
Q16AIPMT 2012 Prelims
When a mass is rotating in a plane about a fixed point, its angular momentum is directed along:
Not quite — the answer is B.
Angular momentum L = r × p, and both r and p lie in the plane of rotation, so L is perpendicular to that plane. The tangent is the direction of linear momentum, and the radius is the direction of r.
Q17AIPMT 2012 Prelims
Two sources of sound placed close to each other are emitting progressive waves given by y₁ = 4 sin 600πt and y₂ = 5 sin 608πt. An observer located near these two sources of sound will hear
Not quite — the answer is A.
ω₁ = 600π gives f₁ = 300 Hz and ω₂ = 608π gives f₂ = 304 Hz, so beat frequency = 4 per second. Intensity ratio I_max/I_min = (A₁ + A₂)²/(A₁ − A₂)² = 9²/1² = 81 : 1. 25 : 16 is just the ratio of individual intensities, and 8 beats comes from using ω/2π wrongly.
Q18AIPMT 2012 Prelims
A car of mass 1000 kg negotiates a banked curve of radius 90 m on a frictionless road. If the banking angle is 45°, the speed of the car is
Not quite — the answer is C.
On a frictionless banked road, tan θ = v²/(rg). With θ = 45°, v = √(rg) = √(90 × 10) = 30 m s⁻¹ (g = 10 m s⁻²). The mass of the car does not enter the result.
Q19AIPMT 2012 Prelims
The magnifying power of a telescope is 9. When it is adjusted for parallel rays the distance between the objective and eyepiece is 20 cm. The focal length of lenses are
Not quite — the answer is D.
For normal adjustment, magnifying power = f₀/fₑ = 9 and tube length = f₀ + fₑ = 20 cm. Solving, fₑ = 2 cm and f₀ = 18 cm. 15 cm and 5 cm add to 20 cm but give a magnification of only 3.
Q20AIPMT 2012 Prelims
What is the flux through a cube of side a if a point charge of q is at one of its corners?
Not quite — the answer is C.
A charge at a corner can be enclosed symmetrically by 8 identical cubes, so each cube receives 1/8 of the total flux q/ε₀, i.e. q/(8ε₀). q/ε₀ would apply only if the charge were inside the cube.
Q21AIPMT 2012 Prelims
An α-particle moves in a circular path of radius 0.83 cm in the presence of a magnetic field of 0.25 Wb/m². The de Broglie wavelength associated with the particle will be
Not quite — the answer is A.
In a magnetic field, momentum p = qBr with q = 2e for an α-particle. λ = h/(2eBr) = 6.63 × 10⁻³⁴/(2 × 1.6 × 10⁻¹⁹ × 0.25 × 0.83 × 10⁻²) ≈ 1.0 × 10⁻¹² m = 0.01 Å. Taking the charge as e instead of 2e doubles the wavelength.
Q22AIPMT 2012 Prelims
A spherical planet has a mass Mp and diameter Dp. A particle of mass m falling freely near the surface of this planet will experience an acceleration due to gravity, equal to
Not quite — the answer is B.
g = GM/R² and R = Dₚ/2, so g = GMₚ/(Dₚ/2)² = 4GMₚ/Dₚ². Acceleration does not depend on the particle's mass m, so expressions containing m are forces, not accelerations.
Q23AIPMT 2012 Prelims
A 200 W sodium street lamp emits yellow light of wavelength 0.6 µm. Assuming it to be 25% efficient in converting electrical energy to light, the number of photons of yellow light it emits per second is
Not quite — the answer is B.
Light power = 25% of 200 W = 50 W. Energy per photon = hc/λ = (6.63 × 10⁻³⁴ × 3 × 10⁸)/(0.6 × 10⁻⁶) ≈ 3.3 × 10⁻¹⁹ J. Number per second = 50/3.3 × 10⁻¹⁹ ≈ 1.5 × 10²⁰. Using the full 200 W gives about 6 × 10²⁰, ignoring the efficiency.
Q24AIPMT 2012 Prelims
The potential energy of a particle in a force field is U = A/r² − B/r, where A and B are positive constants and r is the distance of particle from the centre of the field. For stable equilibrium the distance of the particle is
Not quite — the answer is C.
Equilibrium needs dU/dr = −2A/r³ + B/r² = 0, giving r = 2A/B. At this r, d²U/dr² = 6A/r⁴ − 2B/r³ = B⁴/(8A³) > 0, so U is a minimum and the equilibrium is stable. A/B is where U itself is zero, not where the force is zero.
Q25AIPMT 2012 Prelims
An electron of a stationary hydrogen atom passes from the fifth energy level to the ground level. The velocity that the atom acquired as a result of photon emission will be (m is the mass of the electron, R the Rydberg constant and h Planck's constant)
Not quite — the answer is B.
The photon energy for n = 5 → 1 is E = hcR(1 − 1/25) = (24/25)hcR. Its momentum p = E/c = (24/25)hR, and the atom recoils with equal momentum, so v = p/m = 24hR/(25m). The inverted forms have wrong dimensions for velocity.
Q26AIPMT 2012 Prelims
Monochromatic radiation emitted when an electron in hydrogen atom jumps from first excited to the ground state irradiates a photosensitive material. The stopping potential is measured to be 3.57 V. The threshold frequency of the material is
Not quite — the answer is D.
The n = 2 → 1 transition in hydrogen emits a 10.2 eV photon. Work function = 10.2 − 3.57 = 6.63 eV = 6.63 × 1.6 × 10⁻¹⁹ J. Threshold frequency ν₀ = φ/h = (6.63 × 1.6 × 10⁻¹⁹)/(6.63 × 10⁻³⁴) = 1.6 × 10¹⁵ Hz. Using the full 10.2 eV gives about 2.5 × 10¹⁵ Hz, which is the photon frequency, not the threshold.
Q27AIPMT 2012 Prelims
A mixture consists of two radioactive materials A₁ and A₂ with half lives of 20 s and 10 s respectively. Initially the mixture has 40 g of A₁ and 160 g of A₂. The amount of the two in the mixture will become equal after
Not quite — the answer is A.
After t seconds, A₁ = 40(½)^(t/20) and A₂ = 160(½)^(t/10). Equating: 4 = 2^(t/10 − t/20) = 2^(t/20), so t/20 = 2 and t = 40 s. Check: both become 10 g at 40 s.
Q28AIPMT 2012 Prelims
If voltage across a bulb rated 220 V–100 W drops by 2.5% of its rated value, the percentage of the rated value by which the power would decrease is
Not quite — the answer is D.
For a fixed resistance, P = V²/R, so ΔP/P ≈ 2ΔV/V = 2 × 2.5% = 5%. (Exactly, (0.975)² = 0.951, a 4.9% drop.) 2.5% wrongly assumes power proportional to voltage.
Q29AIPMT 2012 Prelims
C and Si both have same lattice structure, having 4 bonding electrons in each. However, C is insulator where as Si is intrinsic semiconductor. This is because
Not quite — the answer is D.
Carbon's four bonding electrons are in the second shell (n = 2) and silicon's in the third (n = 3). The more tightly bound carbon electrons give a much larger band gap (about 5.5 eV vs 1.1 eV), so diamond is an insulator. A partly filled band at absolute zero would make carbon a conductor, not an insulator.
Q30AIPMT 2012 Prelims
Two persons of masses 55 kg and 65 kg respectively, are at the opposite ends of a boat. The length of the boat is 3.0 m and weighs 100 kg. The 55 kg man walks up to the 65 kg man and sits with him. If the boat is in still water the centre of mass of the system shifts by
Not quite — the answer is D.
The man, the other man and the boat form an isolated system with no external horizontal force (still water, friction-free), so the centre of mass of the system cannot move. The boat moves back as the man walks, but the common centre of mass shifts by zero.
Q31AIPMT 2012 Prelims
The motion of a particle along a straight line is described by equation x = 8 + 12t − t³, where x is in metre and t in second. The retardation of the particle when its velocity becomes zero is
Not quite — the answer is A.
v = dx/dt = 12 − 3t², which is zero at t = 2 s. a = dv/dt = −6t = −12 m s⁻² at t = 2 s, so the retardation is 12 m s⁻². Zero is wrong because velocity being zero does not make acceleration zero.
Q32AIPMT 2012 Prelims
A millivoltmeter of 25 millivolt range is to be converted into an ammeter of 25 ampere range. The value (in ohm) of necessary shunt will be
Not quite — the answer is B.
The meter gives full deflection at 25 mV across it; with the shunt carrying almost all 25 A, the shunt resistance is S ≈ V/I = 25 × 10⁻³/25 = 10⁻³ Ω = 0.001 Ω. 0.01 Ω would pass only 2.5 A at 25 mV.
Q33AIPMT 2012 Prelims
The damping force on an oscillator is directly proportional to the velocity. The units of the constant of proportionality are
Not quite — the answer is D.
F = bv, so b = F/v with units (kg m s⁻²)/(m s⁻¹) = kg s⁻¹. kg m s⁻² is the unit of force itself, not of the constant.
Q34AIPMT 2012 Prelims
A ray of light is incident at an angle of incidence i on one face of a prism of angle A (assumed to be small) and emerges normally from the opposite face. If the refractive index of the prism is μ, the angle of incidence i is nearly equal to
Not quite — the answer is B.
Normal emergence means r₂ = 0, so r₁ = A − r₂ = A. Snell's law at the first face: sin i = μ sin A. For small angles, i ≈ μA. A/μ would come from inverting Snell's law.
Q35AIPMT 2012 Prelims
Electron in hydrogen atom first jumps from third excited state to second excited state and then from second excited to the first excited state. The ratio of the wavelengths λ₁ : λ₂ emitted in the two cases is
Not quite — the answer is A.
Third excited state n = 4 → second excited n = 3: 1/λ₁ = R(1/9 − 1/16) = 7R/144. Second excited n = 3 → first excited n = 2: 1/λ₂ = R(1/4 − 1/9) = 5R/36 = 20R/144. Ratio λ₁/λ₂ = 20/7. Taking excited state numbers as n values directly gives a wrong ratio.
Q36AIPMT 2012 Prelims
The electric field associated with an e.m. wave in vacuum is given by E⃗ = î 40 cos(kz − 6 × 10⁸ t), where E, z and t are in volt/m, metre and seconds respectively. The value of wave vector k is
Not quite — the answer is B.
From E = E₀ cos(kz − ωt), ω = 6 × 10⁸ rad s⁻¹. In vacuum c = ω/k, so k = 6 × 10⁸/(3 × 10⁸) = 2 m⁻¹. 0.5 m⁻¹ comes from inverting the ratio.
Q37AIPMT 2012 Prelims
In an electrical circuit R, L, C and an a.c. voltage source are all connected in series. When L is removed from the circuit, the phase difference between the voltage and the current in the circuit is π/3. If instead, C is removed from the circuit, the phase difference is again π/3. The power factor of the circuit is
Not quite — the answer is D.
Removing L: tan(π/3) = X_C/R; removing C: tan(π/3) = X_L/R. So X_L = X_C = √3R and with all three present the circuit is at resonance: Z = R, power factor cos φ = 1. 1/2 is the power factor of each reduced circuit, not of the full RLC circuit.
Physics: not in the current NEET syllabus
These 2 questions are from topics NCERT dropped in its 2023 revision. Shown for completeness; you can skip them for NEET 2027.
2 questions. Tap an option to check your answer.
Q1AIPMT 2012 Prelims
A compass needle which is allowed to move in a horizontal plane is taken to a geomagnetic pole. It:
Not quite — the answer is C.
At a geomagnetic pole the earth's field is vertical, so its horizontal component is zero. A needle free to move only in a horizontal plane experiences no directing torque and stays in any position it is placed. It does not lock into north-south because there is no horizontal field to align it.
Q2AIPMT 2012 Prelims
An alternating electric field, of frequency ν, is applied across the dees (radius = R) of a cyclotron that is being used to accelerate protons (mass = m). The operating magnetic field (B) used in the cyclotron and the kinetic energy (K) of the proton beam, produced by it, are given by
Not quite — the answer is D.
The dee voltage frequency must equal the cyclotron frequency ν = eB/(2πm), so B = 2πmν/e. At the dee radius R, v = eBR/m = 2πνR, so K = ½mv² = ½m(2πνR)² = 2π²mν²R². B = mν/e misses the 2π factor between ν and angular frequency.
Chapter-wise split of AIPMT 2012 Prelims Physics
- System of Particles and Rotational Motion3 Q
- Ray Optics and Optical Instruments3 Q
- Gravitation3 Q
- Dual Nature of Radiation and Matter3 Q
- Semiconductor Electronics: Materials, Devices and Simple Circuits2 Q
- Electrostatic Potential and Capacitance2 Q
- Motion in a Plane2 Q
- Nuclei2 Q
- Moving Charges and Magnetism2 Q
- Waves2 Q
- Current Electricity2 Q
- Atoms2 Q
- Electromagnetic Induction1 Q
- Thermal Properties of Matter1 Q
- Laws of Motion1 Q
- Electric Charges and Fields1 Q
- Work, Energy and Power1 Q
- Motion in a Straight Line1 Q
- Units and Measurements1 Q
- Electromagnetic Waves1 Q
- Alternating Current1 Q
AIPMT 2012 Prelims Chemistry questions
35 questions. Tap an option to check your answer.
Q1AIPMT 2012 Prelims
CH₃CHO and C₆H₅CH₂CHO can be distinguished chemically by
Not quite — the answer is C.
CH₃CHO contains a CH₃CO– group and gives a yellow iodoform precipitate with I₂/NaOH, while C₆H₅CH₂CHO has no methyl ketone/aldehyde group and does not. Both are aldehydes with α-hydrogen, so both reduce Tollens' reagent and (being aliphatic-type aldehydes) Fehling's and Benedict's solutions, which therefore cannot distinguish them.
Q2AIPMT 2012 Prelims
pA and pB are the vapour pressures of pure liquid components A and B, respectively, of an ideal binary solution. If xA represents the mole fraction of component A, the total pressure of the solution will be
Not quite — the answer is A.
By Raoult's law, p = pA·xA + pB·xB with xB = 1 − xA, so p = pB + xA(pA − pB). The expression starting with pA would require the mole fraction of B to multiply (pB − pA).
Q3AIPMT 2012 Prelims
Equimolar solutions of the following substances were prepared separately. Which one of these will record the highest pH value?
Not quite — the answer is B.
BaCl₂ is a salt of a strong acid and a strong base, so it does not hydrolyse and its solution is neutral (pH ≈ 7). BeCl₂ and AlCl₃ hydrolyse strongly to give acidic solutions, and LiCl is very slightly acidic due to the small, polarising Li⁺. So BaCl₂ has the highest pH.
Q4AIPMT 2012 Prelims
In the following reaction: (CH₃)₃C–CH=CH₂ —(H₂O/H⁺)→ A (major product) + B (minor product) The major product is
Not quite — the answer is B.
Protonation of the alkene gives the secondary carbocation (CH₃)₃C–C⁺H–CH₃, which undergoes a 1,2-methyl shift to the more stable tertiary carbocation (CH₃)₂C⁺–CH(CH₃)₂. Water attacks this to give 2,3-dimethylbutan-2-ol, (CH₃)₂C(OH)–CH(CH₃)₂. The unrearranged alcohol (CH₃)₃C–CH(OH)–CH₃ is the minor product.
Q5AIPMT 2012 Prelims
The enthalpy of fusion of water is 1.435 kcal/mol. The molar entropy change for the melting of ice at 0°C is
Not quite — the answer is D.
ΔS_fus = ΔH_fus/T = 1435 cal mol⁻¹/273 K = 5.26 cal mol⁻¹ K⁻¹. 0.526 results from a misplaced decimal and 10.52 from doubling.
Q6AIPMT 2012 Prelims
Limiting molar conductivity of NH₄OH, i.e. Λ°m(NH₄OH), is equal to
Not quite — the answer is A.
By Kohlrausch's law, Λ°m(NH₄OH) = λ°(NH₄⁺) + λ°(OH⁻) = [λ°(NH₄⁺) + λ°(Cl⁻)] + [λ°(Na⁺) + λ°(OH⁻)] − [λ°(Na⁺) + λ°(Cl⁻)] = Λ°m(NH₄Cl) + Λ°m(NaOH) − Λ°m(NaCl). The combination subtracting NaOH would cancel the OH⁻ contribution instead.
Q7AIPMT 2012 Prelims
Buffer solutions have constant acidity and alkalinity because:
Not quite — the answer is B.
A buffer contains a weak acid with its conjugate base (or a weak base with its conjugate acid). Added H⁺ or OH⁻ is consumed to form the weakly ionised acid or base, so [H⁺] changes very little. A buffer's pH is not fixed absolutely (it depends on the ratio of components), and it does not hold a large excess of H⁺ or OH⁻.
Q8AIPMT 2012 Prelims
Which one of the following pairs is isostructural (i.e. having the same shape and hybridization)?
Not quite — the answer is A.
In BF₄⁻ and NH₄⁺ the central atom has four bond pairs and no lone pair: sp³, tetrahedral. BCl₃ is trigonal planar while BrCl₃ is T-shaped; NH₃ is pyramidal while NO₃⁻ is trigonal planar; NF₃ is pyramidal while BF₃ is planar.
Q9AIPMT 2012 Prelims
pH of a saturated solution of Ba(OH)₂ is 12. The value of solubility product (Ksp) of Ba(OH)₂ is
Not quite — the answer is C.
pH 12 means pOH = 2 and [OH⁻] = 10⁻² M, so [Ba²⁺] = 5 × 10⁻³ M. Ksp = [Ba²⁺][OH⁻]² = 5 × 10⁻³ × (10⁻²)² = 5 × 10⁻⁷. Writing 4s³ with s = 10⁻² wrongly treats [OH⁻] as the solubility, giving 4 × 10⁻⁶.
Q10AIPMT 2012 Prelims
Deficiency of vitamin B₁ causes the disease
Not quite — the answer is C.
Thiamine (vitamin B₁) deficiency causes beri-beri. Cheilosis is caused by riboflavin (B₂) deficiency, convulsions by pyridoxine (B₆) deficiency and sterility by vitamin E deficiency.
Q11AIPMT 2012 Prelims
Acetone is treated with excess of ethanol in the presence of hydrochloric acid. The product obtained is:
Not quite — the answer is A.
In dry HCl, acetone adds one ethanol to give a hemiketal, which with excess ethanol loses water and adds a second ethanol to give the ketal 2,2-diethoxypropane, (CH₃)₂C(OC₂H₅)₂. The hemiketal (CH₃)₂C(OH)(OC₂H₅) is only the intermediate, and no C–C bond forming product like a higher ketone is formed.
Q12AIPMT 2012 Prelims
Which one of the following statements is incorrect about enzyme catalysis?
Not quite — the answer is A.
Enzymes show maximum (not least) activity at their optimum temperature, so that statement is incorrect. The other statements are true: most enzymes are proteins, their action is highly specific, and heat or UV radiation denatures them.
Q13AIPMT 2012 Prelims
In which of the following compounds, nitrogen exhibits highest oxidation state?
Not quite — the answer is D.
Oxidation states of N: NH₂OH −1, N₂H₄ −2, NH₃ −3, and in N₃H (hydrazoic acid) 3x + 1 = 0, so x = −1/3. The highest (least negative) is −1/3 in N₃H. NH₂OH at −1 is the nearest trap.
Q14AIPMT 2012 Prelims
Bond order of 1.5 is shown by:
Not quite — the answer is C.
By MO theory, O₂⁻ has 10 bonding and 7 antibonding electrons (valence), bond order = (10 − 7)/2 = 1.5. O₂ is 2, O₂⁺ is 2.5 and O₂²⁻ is 1.
Q15AIPMT 2012 Prelims
Maximum number of electrons in a subshell with l = 3 and n = 4 is:
Not quite — the answer is B.
l = 3 is an f subshell, with 2l + 1 = 7 orbitals, each holding 2 electrons: 14 electrons. The value n = 4 only fixes the shell (4f) and does not change the subshell capacity; 10 is the capacity of a d subshell (l = 2).
Q16AIPMT 2012 Prelims
The correct set of four quantum numbers for the valence electron of rubidium atom (Z = 37) is
Not quite — the answer is D.
Rb (Z = 37) is [Kr] 5s¹, so the valence electron has n = 5, l = 0 (s), m = 0 and s = +½. Sets with l = 1 describe a 5p electron, and n = 6 is the wrong shell.
Q17AIPMT 2012 Prelims
In a reaction, A + B → Product, rate is doubled when the concentration of B is doubled, and rate increases by a factor of 8 when the concentrations of both the reactants (A and B) are doubled. Rate law for the reaction can be written as
Not quite — the answer is A.
Let rate = k[A]^x[B]^y. Doubling [B] doubles the rate, so y = 1. Doubling both gives 2^(x+1) = 8, so x = 2. Rate = k[A]²[B]. k[A][B]² would also give 8 for doubling both, but it would quadruple, not double, the rate on doubling [B].
Q18AIPMT 2012 Prelims
Which one of the following sets of monosaccharides forms sucrose?
Not quite — the answer is C.
Sucrose is formed by a glycosidic link between C1 of α-D-glucopyranose and C2 of β-D-fructofuranose. Fructose occurs as the five-membered furanose ring in sucrose, not as fructopyranose, and galactose is a component of lactose.
Q19AIPMT 2012 Prelims
In the following sequence of reactions CH₃–Br —(KCN)→ A —(H₃O⁺)→ B —(LiAlH₄, ether)→ C, the end product (C) is
Not quite — the answer is A.
CH₃Br + KCN gives CH₃CN; acid hydrolysis converts it to CH₃COOH; LiAlH₄ then reduces the acid to CH₃CH₂OH, ethyl alcohol, as the end product. Acetaldehyde is not isolated because LiAlH₄ reduces carboxylic acids all the way to primary alcohols.
Q20AIPMT 2012 Prelims
Which of the following acids does not exhibit optical isomerism?
Not quite — the answer is B.
Maleic acid (cis-HOOC–CH=CH–COOH) is planar with no chiral carbon, so it shows geometrical but not optical isomerism. Lactic acid, tartaric acid and α-amino acids (except glycine) have chiral carbons.
Q21AIPMT 2012 Prelims
Which nomenclature is not according to IUPAC system?
Not quite — the answer is B.
Br–CH₂–CH=CH₂ must be numbered to give the double bond the lowest locant, so its IUPAC name is 3-bromoprop-1-ene, not 1-bromoprop-2-ene. The other names are correct: 5-oxohexanoic acid, 4-bromo-2,4-dimethylhexane (locants 2,4,4 beat 3,3,5) and (2-methylpentan-3-yl)benzene.
Q22AIPMT 2012 Prelims
The pair of species with the same bond order is
Not quite — the answer is B.
O₂²⁻ (18 electrons) has bond order 1 and B₂ (10 electrons) also has bond order 1. N₂ = 3 vs O₂ = 2; O₂⁺ = 2.5 vs NO⁺ = 3; NO = 2.5 vs CO = 3.
Q23AIPMT 2012 Prelims
The correct order of decreasing acid strength of trichloroacetic acid (A), trifluoroacetic acid (B), acetic acid (C) and formic acid (D) is:
Not quite — the answer is B.
Electron-withdrawing (−I) groups stabilise the carboxylate ion. F is more electronegative than Cl, so CF₃COOH > CCl₃COOH; HCOOH is stronger than CH₃COOH because CH₃ is electron-releasing. Order: trifluoroacetic > trichloroacetic > formic > acetic.
Q24AIPMT 2012 Prelims
Which of the following species contains three bond pairs and one lone pair around the central atom?
Not quite — the answer is A.
P in PCl₃ has 5 valence electrons: three form bonds with Cl and two remain as one lone pair (pyramidal). H₂O and NH₂⁻ each have two bond pairs and two lone pairs, and BF₃ has three bond pairs and no lone pair.
Q25AIPMT 2012 Prelims
Among the following compounds the one that is most reactive towards electrophilic nitration is:
Not quite — the answer is D.
The –CH₃ group of toluene donates electron density to the ring (+I and hyperconjugation), activating it for electrophilic nitration, so toluene reacts faster than benzene. –COOH and –NO₂ withdraw electrons and deactivate the ring.
Q26AIPMT 2012 Prelims
Identify the wrong statement in the following:
Not quite — the answer is B.
In an isoelectronic series, a larger positive charge pulls the same number of electrons more strongly and gives a smaller radius; so a smaller positive charge gives a larger, not smaller, radius. The other statements are correct: radius decreases across a period, increases down a group, and increases with greater negative charge.
Q27AIPMT 2012 Prelims
In a zero-order reaction for every 10° rise of temperature, the rate is doubled. If the temperature is increased from 10°C to 100°C, the rate of the reaction will become:
Not quite — the answer is C.
From 10 °C to 100 °C is a 90° rise, i.e. nine 10° steps. Rate becomes 2⁹ = 512 times. 256 (2⁸) comes from miscounting the steps. The zero order of the reaction does not affect the temperature factor.
Q28AIPMT 2012 Prelims
Which of the statements is not true?
Not quite — the answer is C.
Na₂Cr₂O₇ is hygroscopic, so K₂Cr₂O₇, which is not, is preferred as a primary standard in volumetric analysis; the statement favouring sodium dichromate is false. The others are true: raising pH converts orange Cr₂O₇²⁻ to yellow CrO₄²⁻, and H₂S is oxidised to colloidal sulphur, giving a milky appearance.
Q29AIPMT 2012 Prelims
In which of the following reactions, standard reaction entropy change (ΔS°) is positive and standard Gibbs energy change (ΔG°) decreases sharply with increasing temperature?
Not quite — the answer is B.
In C(graphite) + ½O₂(g) → CO(g), gaseous moles increase from ½ to 1, so ΔS° is clearly positive and ΔG° = ΔH° − TΔS° falls steeply as T rises. Forming CO₂ from C keeps gas moles unchanged (ΔS° ≈ 0), while CO → CO₂ and Mg → MgO decrease gas moles (ΔS° < 0).
Q30AIPMT 2012 Prelims · Q29
Which of the following statements is not valid for oxoacids of phosphorus?
Not quite — the answer is C.
Hypophosphorous acid, H₃PO₂, has two P–H bonds and only one P–OH group, so it is monoprotic (monobasic), not diprotic. All phosphorus oxoacids do contain tetrahedral four-coordinated P with at least one P=O and one P–OH, and H₃PO₄ is used to make triple superphosphate.
Q31AIPMT 2012 Prelims
Predict the products in the given reaction: m-Chlorobenzaldehyde (m-Cl–C₆H₄–CHO) —(50% KOH)→ ?
Not quite — the answer is D.
m-Chlorobenzaldehyde has no α-hydrogen, so with concentrated (50%) KOH it undergoes the Cannizzaro reaction: one molecule is reduced to m-chlorobenzyl alcohol and another oxidised to m-chlorobenzoate. The aryl C–Cl bond is not hydrolysed under these conditions, so products with –OH replacing Cl are wrong.
Q32AIPMT 2012 Prelims
Which one of the following is an outer orbital complex and exhibits paramagnetic behaviour?
Not quite — the answer is B.
Ni²⁺ is d⁸; in an octahedral complex the two remaining inner d orbitals are not vacant, so it uses 4s4p³4d² (sp³d², outer orbital) and keeps two unpaired electrons, making it paramagnetic. [Co(NH₃)₆]³⁺ is inner orbital and diamagnetic, [Zn(NH₃)₆]²⁺ is outer orbital but diamagnetic (d¹⁰), and [Cr(NH₃)₆]³⁺ is inner orbital (d²sp³).
Q33AIPMT 2012 Prelims
Standard enthalpy of vapourisation ΔvapH° for water at 100°C is 40.66 kJ mol⁻¹. The internal energy of vapourisation of water at 100°C (in kJ mol⁻¹) is
Not quite — the answer is B.
For H₂O(l) → H₂O(g), Δn_g = 1. ΔU = ΔH − Δn_gRT = 40.66 − (8.314 × 10⁻³ × 373) = 40.66 − 3.10 = 37.56 kJ mol⁻¹. 43.76 comes from adding RT instead of subtracting it.
Q34AIPMT 2012 Prelims · Q45
When Cl₂ gas reacts with hot and concentrated sodium hydroxide solution, the oxidation number of chlorine changes from
Not quite — the answer is C.
With hot concentrated NaOH, chlorine disproportionates: 3Cl₂ + 6NaOH → 5NaCl + NaClO₃ + 3H₂O. Chlorine goes from 0 to −1 in chloride and 0 to +5 in chlorate. The change 0 to +1 (hypochlorite) occurs with cold dilute NaOH.
Q35AIPMT 2012 Prelims · Q49
Sulphur trioxide can be obtained by which of the following reactions?
Not quite — the answer is C.
Iron(III) sulphate decomposes on heating: Fe₂(SO₄)₃ → Fe₂O₃ + 3SO₃. Sulphur with hot concentrated H₂SO₄ gives SO₂, H₂SO₄ with PCl₅ gives chlorosulphonic acid/sulphuryl chloride, and CaSO₄ with carbon is reduced to CaS or SO₂, not SO₃.
Chemistry: not in the current NEET syllabus
These 12 questions are from topics NCERT dropped in its 2023 revision. Shown for completeness; you can skip them for NEET 2027.
12 questions. Tap an option to check your answer.
Q1AIPMT 2012 Prelims · Q3
Which one of the following is not a condensation polymer?
Not quite — the answer is A.
Neoprene is an addition polymer formed by free-radical polymerisation of chloroprene, with no small molecule eliminated. Melamine–formaldehyde resin, glyptal and dacron are all formed by condensation with loss of water.
Q2AIPMT 2012 Prelims · Q4
A metal crystallizes with a face-centered cubic lattice. The edge of the unit cell is 408 pm. The diameter of the metal atom is
Not quite — the answer is B.
In an fcc lattice atoms touch along the face diagonal: 4r = √2 a, so the diameter 2r = a/√2 = 408/1.414 ≈ 288 pm. 204 pm is just half the edge length, which is valid for simple cubic contact only along the edge.
Q3AIPMT 2012 Prelims · Q9
Which one of the following is a mineral of iron?
Not quite — the answer is A.
Magnetite, Fe₃O₄, is an iron ore. Malachite is a copper ore (CuCO₃·Cu(OH)₂), cassiterite is tin ore (SnO₂) and pyrolusite is manganese ore (MnO₂).
Q4AIPMT 2012 Prelims · Q10
In Freundlich Adsorption isotherm, the value of 1/n is:
Not quite — the answer is B.
In the Freundlich isotherm x/m = kp^(1/n), the exponent 1/n lies between 0 and 1, reflecting that adsorption rises less than proportionally with pressure. 1/n = 1 is only the limiting low-pressure case and is not specific to either physisorption or chemisorption.
Q5AIPMT 2012 Prelims · Q11
Identify the alloy containing a non-metal as a constituent in it.
Not quite — the answer is C.
Steel is an alloy of iron with carbon, a non-metal. Bronze (Cu–Sn), invar (Fe–Ni) and bell metal (Cu–Sn) contain only metals.
Q6AIPMT 2012 Prelims · Q16
The protecting power of lyophilic colloidal sol is expressed in terms of
Not quite — the answer is C.
The protective power of a lyophilic colloid is expressed by its gold number: the milligrams of it needed to prevent coagulation of 10 mL of gold sol by 1 mL of 10% NaCl. Coagulation value refers to electrolytes coagulating a sol, not to protection.
Q7AIPMT 2012 Prelims · Q28
Which one of the following statements regarding photochemical smog is not correct?
Not quite — the answer is A.
Photochemical smog contains ozone, PAN and aldehydes and causes irritation of the eyes and throat, so the statement saying it does not is incorrect. It is oxidising, forms through sunlight-driven reactions of NOx and hydrocarbons, and CO does not play a role in its formation.
Q8AIPMT 2012 Prelims · Q34
In the extraction of copper from its sulphide ore, the metal is finally obtained by the reduction of cuprous oxide with:
Not quite — the answer is B.
In the Bessemer converter, part of Cu₂S is oxidised to Cu₂O, which then reacts with remaining Cu₂S (self-reduction): 2Cu₂O + Cu₂S → 6Cu + SO₂. SO₂ is a product, not the reducing agent, and CO is not used for copper from sulphide ores.
Q9AIPMT 2012 Prelims · Q36
Aluminium is extracted from alumina (Al₂O₃) by electrolysis of a molten mixture of
Not quite — the answer is D.
In the Hall–Héroult process, alumina is electrolysed in molten cryolite (Na₃AlF₆) with fluorspar (CaF₂) added to lower the melting point and raise conductivity. KF, HF and NaAlF₄ are not used.
Q10AIPMT 2012 Prelims · Q38
Which of the following statements is false?
Not quite — the answer is C.
Nylon-66 is a polyamide fibre with strong hydrogen bonding between chains, not an elastomer (rubber-like polymer). The other statements are correct: starch and cellulose are glucose polymers, rayon (artificial silk) is regenerated cellulose, and natural rubber is a polymer of isoprene.
Q11AIPMT 2012 Prelims · Q39
The number of octahedral void(s) per atom present in a cubic close-packed structure is
Not quite — the answer is B.
A ccp (fcc) unit cell has 4 atoms and 4 octahedral voids (1 at the body centre + 12 edge centres × ¼), so there is 1 octahedral void per atom. 2 is the number of tetrahedral voids per atom.
Q12AIPMT 2012 Prelims · Q47
Which one of the alkali metals forms only the normal oxide, M₂O, on heating in air?
Not quite — the answer is D.
Lithium, the smallest alkali metal ion, forms only the normal oxide Li₂O on burning in air. Sodium forms mainly the peroxide Na₂O₂, while potassium and rubidium form superoxides MO₂.
Chapter-wise split of AIPMT 2012 Prelims Chemistry
- Aldehydes, Ketones and Carboxylic Acids5 Q
- Chemical Bonding and Molecular Structure4 Q
- Equilibrium3 Q
- Thermodynamics3 Q
- Biomolecules3 Q
- Alcohols, Phenols and Ethers2 Q
- Structure of Atom2 Q
- Chemical Kinetics2 Q
- Solutions1 Q
- Electrochemistry1 Q
- Redox Reactions1 Q
- Organic Chemistry: Some Basic Principles and Techniques1 Q
- Hydrocarbons1 Q
- Classification of Elements and Periodicity in Properties1 Q
- The d- and f-Block Elements1 Q
- Coordination Compounds1 Q
AIPMT 2012 Prelims Biology questions
76 questions. Tap an option to check your answer.
Q1AIPMT 2012 Prelims
Removal of introns and joining of exons in a defined order during transcription is called
Not quite — the answer is A.
Splicing is the removal of introns from the primary transcript (hnRNA) and joining of exons in a defined order. Slicing is a distractor that sounds similar but is not the term for this process.
Q2AIPMT 2012 Prelims
Common cold differs from pneumonia in that
Not quite — the answer is A.
Pneumonia, caused by bacteria such as Streptococcus pneumoniae, infects the alveoli of the lungs, whereas the common cold (rhinovirus) affects the nose and respiratory passages but not the lungs. The common cold is an infectious viral disease, not a nutritional deficiency, and it is not caused by Haemophilus.
Q3AIPMT 2012 Prelims
Which one of the following is not a property of cancerous cells whereas the remaining three are?
Not quite — the answer is A.
Cancer cells have lost contact inhibition, so they keep dividing even when touching neighbouring cells. Uncontrolled division, spreading from the site of origin (metastasis) and competing with normal cells for nutrients are all true of cancer cells.
Q4AIPMT 2012 Prelims
How many plants in the list given below have composite fruits that develop from an inflorescence? Walnut, poppy, radish, fig, pineapple, apple, tomato, mulberry.
Not quite — the answer is A.
Composite (multiple) fruits develop from a whole inflorescence: fig (syconus), pineapple (sorosis) and mulberry (sorosis), which makes three. Walnut, poppy, radish, apple and tomato develop from a single flower.
Q5AIPMT 2012 Prelims
An organic substance that can withstand environmental extremes and cannot be degraded by any enzyme is
Not quite — the answer is C.
Sporopollenin in the exine of pollen grains is one of the most resistant organic materials; it withstands high temperatures and strong acids and alkalis, and no known enzyme degrades it. Lignin and cellulose are both broken down by microbial enzymes.
Q6AIPMT 2012 Prelims
Both, autogamy and geitonogamy are prevented in
Not quite — the answer is B.
Papaya is dioecious (male and female flowers on separate plants), so neither autogamy nor geitonogamy is possible. Maize, castor and cucumber are monoecious, which prevents autogamy but still allows geitonogamy.
Q7AIPMT 2012 Prelims
Water containing cavities in vascular bundles are found in
Not quite — the answer is C.
In monocot stems such as maize, the protoxylem breaks down to leave water-containing cavities (lysigenous cavities) in each vascular bundle. Sunflower is a dicot, and Pinus and Cycas are gymnosperms that do not show this feature.
Q8AIPMT 2012 Prelims
Which one of the following is a case of wrong matching ?
Not quite — the answer is C.
A vector DNA (such as a plasmid) carries the foreign gene into the host cell and lets it replicate; it is not a site of tRNA synthesis. Callus, somatic hybridisation and micropropagation are all correctly described.
Q9AIPMT 2012 Prelims
Which one of the structures given below correctly represents the structural formula of the basic amino acid?
Not quite — the answer is B.
Lysine, H₂N–CH(COOH)–(CH₂)₄–NH₂, carries an extra amino group in its side chain, which makes it a basic amino acid. The structure with an extra –COOH in the side chain is glutamic acid (acidic), the one with –CH₂OH is serine (neutral), and HOCH₂–CH₂–CH₂–NH₂ is not an amino acid at all.
Q10AIPMT 2012 Prelims
A patient brought to a hospital with myocardial infarction is normally immediately given
Not quite — the answer is C.
Streptokinase, produced by Streptococcus and modified by genetic engineering, is a clot buster that dissolves blood clots in the coronary arteries of myocardial infarction patients. Statins lower blood cholesterol and cyclosporin A is an immunosuppressant used in organ transplants.
Q11AIPMT 2012 Prelims
Ribosomal RNA is actively synthesized in
Not quite — the answer is C.
The nucleolus is the site of active ribosomal RNA synthesis. Ribosomes are made of rRNA but do not synthesise it, and lysosomes are digestive vesicles.
Q12AIPMT 2012 Prelims
Which one of the following does not differ in E. coli and Chlamydomonas?
Not quite — the answer is A.
Both the prokaryote E. coli and the eukaryotic alga Chlamydomonas have a similar lipid–protein plasma membrane. Their ribosomes (70S versus 80S cytoplasmic), chromosome organisation (naked circular DNA versus chromatin) and cell wall chemistry (peptidoglycan versus cellulose) all differ.
Q13AIPMT 2012 Prelims
Which one is the most abundant protein in the animal world ?
Not quite — the answer is D.
Collagen is the most abundant protein in the animal world. RuBisCO is the most abundant protein in the whole biosphere, but it is a plant protein; haemoglobin, insulin and trypsin are far less abundant.
Q14AIPMT 2012 Prelims
Consumption of which one of the following foods can prevent the kind of blindness associated with vitamin 'A' deficiency?
Not quite — the answer is D.
Golden rice is genetically engineered to make β-carotene (provitamin A), so eating it helps prevent the night blindness caused by vitamin A deficiency. Bt-brinjal is pest resistant and Flavr Savr tomato has delayed ripening.
Q15AIPMT 2012 Prelims
Which one of the following options gives one correct example each of convergent evolution and divergent evolution?
Not quite — the answer is B.
Eyes of octopus and mammals are analogous structures that evolved independently (convergent evolution), while the forelimb bones of vertebrates are homologous structures from a common ancestor (divergent evolution). Thorns of Bougainvillea and tendrils of Cucurbita are homologous, not convergent, and wings of butterflies and birds are analogous, not divergent.
Q16AIPMT 2012 Prelims
The gynoecium consists of many free pistils in flowers of
Not quite — the answer is A.
Michelia has a multicarpellary apocarpous gynoecium, with many free pistils on an elongated thalamus. Papaver, tomato and Aloe have syncarpous ovaries with fused carpels.
Q17AIPMT 2012 Prelims
Evolution of different species in a given area starting from a point and spreading to other geographical areas is known as
Not quite — the answer is B.
Adaptive radiation is the evolution of different species from a single ancestral point, radiating into other geographical areas and habitats, as in Darwin's finches. Divergent evolution describes homologous structures in general, not this pattern of spread.
Q18AIPMT 2012 Prelims
A single strand of nucleic acid tagged with a radioactive molecule is called
Not quite — the answer is A.
A probe is a single-stranded DNA or RNA tagged with a radioactive (or fluorescent) molecule that hybridises with its complementary sequence and is detected by autoradiography. Vectors and plasmids carry genes into hosts, and selectable markers identify transformants.
Q19AIPMT 2012 Prelims
Measuring Biochemical Oxygen Demand (BOD) is a method used for
Not quite — the answer is B.
BOD is the amount of oxygen consumed if all the organic matter in one litre of water were oxidised by bacteria, so it measures the organic matter in sewage. It has nothing to do with RBC oxygen carrying, engines, or curd making, which is in any case done by Lactobacillus and not yeast.
Q20AIPMT 2012 Prelims
Yeast is used in the production of
Not quite — the answer is D.
Saccharomyces cerevisiae (baker's/brewer's yeast) is used to make bread by fermenting dough and to brew beer. Cheese and butter depend on bacteria, citric acid comes from Aspergillus, and lactic acid from Lactobacillus.
Q21AIPMT 2012 Prelims
Maximum nutritional diversity is found in the group
Not quite — the answer is D.
Monera (bacteria) show the widest range of nutrition: photoautotrophs, chemoautotrophs and many kinds of heterotrophs (saprophytes, parasites, symbionts). Plantae are mostly autotrophic and Fungi and Animalia are heterotrophic.
Q22AIPMT 2012 Prelims
Which one of the following is common to multicellular fungi, filamentous algae and protonema of mosses ?
Not quite — the answer is A.
Multicellular fungi, filamentous algae and the filamentous protonema of mosses all multiply vegetatively by fragmentation. They differ in life cycle and nutrition, and fungi are not members of kingdom Plantae.
Q23AIPMT 2012 Prelims
In which one of the following options the two examples are correctly matched with their particular type of immunity?
Not quite — the answer is B.
Polymorphonuclear leukocytes (neutrophils) and monocytes are cellular barriers of innate immunity. Mucus coating is a physical barrier, HCl, saliva and tears are physiological barriers, and anti-tetanus and anti-snake venom injections give passive, not active, immunity.
Q24AIPMT 2012 Prelims
Which one of the following pairs of hormones are the examples of those that can easily pass through the cell membrane of the target cell and bind to a receptor inside it (mostly in the nucleus)?
Not quite — the answer is A.
Cortisol and testosterone are lipid-soluble steroid hormones that pass through the cell membrane and bind to intracellular (mostly nuclear) receptors. Insulin, glucagon, somatostatin and oxytocin are peptide hormones that bind to membrane receptors; thyroxine enters the cell but insulin does not.
Q25AIPMT 2012 Prelims
Closed vascular bundles lack
Not quite — the answer is D.
A closed vascular bundle has no cambium between xylem and phloem, so it cannot form secondary tissue (as in monocots). Pith, ground tissue and conjunctive tissue are not parts of the bundle itself.
Q26AIPMT 2012 Prelims
Which one of the following is a correct statement ?
Not quite — the answer is A.
Heterospory in some pteridophytes such as Selaginella and Salvinia, with the megaspore retained on the parent, is a precursor to the seed habit. Protonema and leafy stages belong to moss gametophytes, antheridiophores and archegoniophores occur in Marchantia (a liverwort), and the female gametophyte of gymnosperms is retained within the ovule, not free-living.
Q27AIPMT 2012 Prelims
Widal test is carried out to test
Not quite — the answer is A.
The Widal test detects antibodies against Salmonella typhi and confirms typhoid fever. Malaria is diagnosed from blood smears, diabetes by blood sugar, and HIV by ELISA.
Q28AIPMT 2012 Prelims
The maximum amount of electrolytes and water (70 – 80 percent) from the glomerular filtrate is reabsorbed in which part of the nephron ?
Not quite — the answer is D.
The proximal convoluted tubule reabsorbs nearly 70–80 percent of the electrolytes and water from the glomerular filtrate. The loop of Henle and the distal tubule handle much smaller amounts.
Q29AIPMT 2012 Prelims
The Test-tube Baby Programme employs which one of the following techniques ?
Not quite — the answer is A.
In the test-tube baby programme, ova are fertilised in vitro and the zygote or early embryo is transferred into the fallopian tube (ZIFT). GIFT transfers unfertilised gametes and IUI places semen in the uterus, so neither involves fertilisation in a test tube.
Q30AIPMT 2012 Prelims
Identify the possible link "A" in the following food chain: Plant → insect → frog → "A" → Eagle
Not quite — the answer is D.
A cobra eats frogs and is in turn eaten by an eagle, so it fits between them. A parrot and a rabbit are herbivores that do not eat frogs, and a wolf is not normally preyed on by an eagle.
Q31AIPMT 2012 Prelims
The human hind brain comprises three parts, one of which is
Not quite — the answer is D.
The hindbrain consists of the pons, cerebellum and medulla oblongata. The hypothalamus is part of the forebrain (diencephalon), the corpus callosum connects the cerebral hemispheres, and the spinal cord is not part of the brain.
Q32AIPMT 2012 Prelims
PCR and Restriction Fragment Length Polymorphism are the methods for
Not quite — the answer is A.
DNA (genetic) fingerprinting uses PCR to amplify DNA and RFLP (restriction digestion and hybridisation with probes) to compare banding patterns between individuals. These methods are not used to study enzymes or to transform cells.
Q33AIPMT 2012 Prelims
Which one of the following areas in India, is a hotspot of biodiversity ?
Not quite — the answer is A.
The Western Ghats (with Sri Lanka) is one of the global biodiversity hotspots in India, alongside the Himalaya and Indo-Burma. The Eastern Ghats, Gangetic plain and Sunderbans are not hotspots.
Q34AIPMT 2012 Prelims
Phyllode is present in
Not quite — the answer is D.
In Australian Acacia the petiole becomes flat, green and leaf-like (a phyllode) and takes over photosynthesis. Opuntia has a phylloclade (flattened stem), Asparagus has cladodes, and Euphorbia has a fleshy stem.
Q35AIPMT 2012 Prelims
The highest number of species in the world is represented by
Not quite — the answer is B.
Of the groups listed, fungi have by far the most described species; they are the largest group after insects in the global species count. Algae, mosses and lichens each have far fewer species.
Q36AIPMT 2012 Prelims
Motile zygote of Plasmodium occurs in
Not quite — the answer is B.
Gametes of Plasmodium fuse in the gut of the female Anopheles mosquito to form a motile zygote (ookinete), which then forms an oocyst on the gut wall. Sporozoites are found in the salivary glands, while the liver and RBCs host the asexual stages in humans.
Q37AIPMT 2012 Prelims
Select the correct statement regarding the specific disorder of muscular or skeletal system
Not quite — the answer is C.
Osteoporosis is an age-related loss of bone mass that raises the chance of fractures. Gout is caused by uric acid crystals (not calcium) in joints, muscular dystrophy is a genetic degeneration of muscle, and myasthenia gravis is an autoimmune disorder of the neuromuscular junction.
Q38AIPMT 2012 Prelims
Vexillary aestivation is characteristic of the family
Not quite — the answer is B.
Vexillary (papilionaceous) aestivation, with a large standard petal overlapping two wings that overlap the keel, is characteristic of Fabaceae such as pea and bean. Brassicaceae, Asteraceae and Solanaceae show other types.
Q39AIPMT 2012 Prelims
Which one of the following is an example of carrying out biological control of pests/diseases using microbes ?
Not quite — the answer is B.
Trichoderma is a free-living fungus used as a biocontrol agent against several plant pathogens, so it is microbial biocontrol. A ladybird beetle is an insect, not a microbe; nucleopolyhedrovirus is used against insect pests, not white rust; and Bt-cotton is a transgenic crop, not biocontrol.
Q40AIPMT 2012 Prelims
The extinct human who lived 1,00,000 to 40,000 years ago, in Europe, Asia and parts of Africa, with short stature, heavy eye brows, retreating foreheads, large jaws with heavy teeth, stocky bodies, a lumbering gait and stooped posture was
Not quite — the answer is C.
The Neanderthal man lived about 1,00,000 to 40,000 years ago in Europe, Asia and parts of Africa, with short stocky bodies, heavy brow ridges, retreating foreheads and large jaws. Cro-Magnon was a later modern human, and Ramapithecus and Homo habilis are much older.
Q41AIPMT 2012 Prelims
A normal-visioned man whose father was colour-blind, marries a woman whose father was also colour-blind. They have their first child as a daughter. What are the chances that this child would be colour-blind ?
Not quite — the answer is C.
The man has normal vision, so his X chromosome carries the normal allele; every daughter receives this X from him. The woman, whose father was colour-blind, is a carrier, but the daughter can be at most a carrier, so her chance of being colour-blind is zero.
Q42AIPMT 2012 Prelims
Even in absence of pollinating agents seed-setting is assured in
Not quite — the answer is B.
Commelina produces cleistogamous flowers that never open and self-pollinate, so seed set is assured even without pollinators. Salvia needs insects, fig depends on fig wasps, and Zostera is water-pollinated.
Q43AIPMT 2012 Prelims
What was the most significant trend in the evolution of modern man (Homo sapiens) from his ancestors?
Not quite — the answer is D.
The most significant trend in human evolution was the increase in cranial capacity (brain size), from about 650–800 cc in Homo habilis to about 1400 cc in Homo sapiens. Upright posture and binocular vision appeared earlier and are shared with other hominids or primates.
Q44AIPMT 2012 Prelims
The most abundant prokaryotes helpful to humans in making curd from milk and in production of antibiotics are the ones categorised as
Not quite — the answer is A.
Heterotrophic bacteria are the most abundant bacteria in nature; Lactobacillus turns milk into curd and Streptomyces produces antibiotics. Cyanobacteria and chemosynthetic autotrophs make their own food, and archaebacteria live in extreme habitats.
Q45AIPMT 2012 Prelims
A person entering an empty room suddenly finds a snake right in front on opening the door. Which one of the following is likely to happen in his neuro-hormonal control system ?
Not quite — the answer is B.
In a fright response the sympathetic nervous system stimulates the adrenal medulla to release epinephrine and norepinephrine (fight-or-flight). These hormones come from the medulla, not the adrenal cortex, and the parasympathetic division is not activated in an emergency.
Q46AIPMT 2012 Prelims
Which one single organism or the pair of organisms is correctly assigned to its or their named taxonomic group?
Not quite — the answer is D.
Yeast used in bread and beer is a fungus (Saccharomyces). Nostoc and Anabaena are Monera, Paramecium and Plasmodium are Protista while Penicillium is a fungus, and a lichen is an alga plus a fungus, not a protozoan.
Q47AIPMT 2012 Prelims
In a normal pregnant woman, the amount of total gonadotropin activity was assessed. The result expected was
Not quite — the answer is A.
During pregnancy the placenta secretes large amounts of hCG, which maintains the corpus luteum so that it keeps secreting oestrogen and progesterone. FSH and LH are suppressed in pregnancy and in any case act on the ovary, not the uterus.
Q48AIPMT 2012 Prelims
The Leydig cells as found in the human body are the secretory source of
Not quite — the answer is A.
Leydig (interstitial) cells lying between the seminiferous tubules secrete androgens, mainly testosterone. Progesterone comes from the corpus luteum, intestinal mucus from goblet cells, and glucagon from α-cells of the pancreas.
Q49AIPMT 2012 Prelims
Which one of the following is not a part of a transcription unit in DNA ?
Not quite — the answer is B.
A transcription unit consists of a promoter, a structural gene and a terminator. An inducer (such as lactose in the lac operon) is a small molecule that regulates expression; it is not a stretch of DNA.
Q50AIPMT 2012 Prelims
Cycas and Adiantum resemble each other in having
Not quite — the answer is C.
Cycas (a gymnosperm) and Adiantum (a fern) both have motile, multiflagellate male gametes. Adiantum has no seeds, neither has vessels, and the fern lacks cambium.
Q51AIPMT 2012 Prelims
A certain road accident patient with unknown blood group needs immediate blood transfusion. His one doctor friend at once offers his blood. What was the blood group of the donor ?
Not quite — the answer is D.
Blood group O has no A or B antigens on its RBCs, so it can be given to a patient of any ABO group; O is the universal donor. Group AB is the universal recipient, not donor.
Q52AIPMT 2012 Prelims
Compared to those of humans, the erythrocytes in frog are
Not quite — the answer is C.
Frog erythrocytes are nucleated and contain haemoglobin, unlike the enucleate RBCs of mammals. They are also larger, not smaller, than human RBCs.
Q53AIPMT 2012 Prelims
A nitrogen-fixing microbe associated with Azolla in rice fields is
Not quite — the answer is C.
The cyanobacterium Anabaena azollae lives in the leaf cavities of the water fern Azolla and fixes nitrogen, so Azolla is used as a biofertiliser in rice fields. Frankia forms nodules on non-legumes like Alnus, and Spirulina is grown as single-cell protein.
Q54AIPMT 2012 Prelims
What is correct to say about the hormone action in humans ?
Not quite — the answer is D.
FSH is a glycoprotein hormone, so in females it first binds to specific receptors on the membrane of ovarian cells. FSH stimulates follicle growth and oestrogen secretion but not progesterone, glucagon comes from α-cells (not β-cells), and thymosin secretion falls with age.
Q55AIPMT 2012 Prelims
Cymose inflorescence is present in
Not quite — the answer is B.
Solanum (Solanaceae) bears a cymose inflorescence, where the main axis ends in a flower. Brassica, Sesbania and Trifolium have racemose inflorescences with indefinite growth of the main axis.
Q56AIPMT 2012 Prelims
Which one of the following is correctly matched ?
Not quite — the answer is B.
Onion is a bulb, an underground stem with fleshy scale leaves. Ginger is a rhizome, yeast reproduces by budding, and Chlamydomonas forms zoospores; conidia are formed by Penicillium.
Q57AIPMT 2012 Prelims
What is true about ribosomes ?
Not quite — the answer is C.
Ribosomes are made of ribosomal RNA and proteins. Prokaryotic ribosomes are 70S (not 80S), ribosomes occur in both prokaryotes and eukaryotes, and they are not introns.
Q58AIPMT 2012 Prelims
A process that makes important difference between C₃ and C₄ plants is
Not quite — the answer is A.
Photorespiration occurs in C₃ plants, where RuBisCO also acts as an oxygenase, but is almost absent in C₄ plants because CO₂ is concentrated around RuBisCO in the bundle sheath. Both types carry out photosynthesis, transpiration and glycolysis.
Q59AIPMT 2012 Prelims
Placentation in tomato and lemon is
Not quite — the answer is A.
Tomato and lemon have axile placentation: a multilocular ovary with ovules attached to the central axis. Parietal placentation is seen in mustard, free central in Dianthus and marginal in pea.
Q60AIPMT 2012 Prelims
Select the correct statement from the following regarding cell membrane
Not quite — the answer is A.
The fluid mosaic model of the cell membrane was proposed by Singer and Nicolson in 1972. Na⁺ and K⁺ are moved by active transport (Na⁺/K⁺ pump), proteins form about half (not 60–70%) of the human RBC membrane, and lipid polar heads face outwards with the tails inside.
Q61AIPMT 2012 Prelims
For transformation, micro-particles coated with DNA to be bombarded with gene gun are made up of
Not quite — the answer is A.
In biolistics (gene gun), DNA is coated onto high-velocity microparticles of gold or tungsten and fired into plant cells. Silver, platinum, zinc and silicon are not used.
Q62AIPMT 2012 Prelims
Which one is a true statement regarding DNA polymerase used in PCR ?
Not quite — the answer is A.
The DNA polymerase used in PCR is Taq polymerase from the bacterium Thermus aquaticus, which stays active at the high temperatures used to denature DNA. It is isolated from a bacterium, not a virus, and it does not ligate DNA or act as a selectable marker.
Q63AIPMT 2012 Prelims
The upright pyramid of number is absent in
Not quite — the answer is C.
In a forest, a few large trees support many herbivores (insects, birds), so the pyramid of numbers is inverted or spindle-shaped rather than upright. Grassland, pond and lake ecosystems have upright pyramids of numbers.
Q64AIPMT 2012 Prelims
Signals for parturition originate from
Not quite — the answer is B.
The signals for parturition come from the fully developed foetus and the placenta; they cause mild uterine contractions (the foetal ejection reflex), which then trigger oxytocin release from the maternal pituitary. Oxytocin is a response to the signal, not its origin.
Q65AIPMT 2012 Prelims
The common bottle cork is a product of
Not quite — the answer is C.
Commercial bottle cork is phellem (cork) produced by the phellogen (cork cambium) of the cork oak, Quercus suber. Vascular cambium produces secondary xylem and phloem, and dermatogen forms the epidermis.
Q66AIPMT 2012 Prelims
Nuclear membrane is absent in
Not quite — the answer is A.
Nostoc is a cyanobacterium, a prokaryote without a nuclear membrane. Penicillium and Agaricus (fungi) and Volvox (green alga) are eukaryotes with a true nucleus.
Q67AIPMT 2012 Prelims
The cyanobacteria are also referred to as
Not quite — the answer is A.
Cyanobacteria are also called blue-green algae because of their pigments and photosynthesis like algae, though they are prokaryotes. Golden algae are chrysophytes and slime moulds are protists.
Q68AIPMT 2012 Prelims
Which one of the following microbes forms symbiotic association with plants and helps them in their nutrition ?
Not quite — the answer is D.
Glomus is a fungus that forms mycorrhiza with plant roots and helps absorb phosphorus from the soil. Azotobacter is a free-living nitrogen fixer and Trichoderma is a free-living biocontrol fungus, not a symbiont.
Q69AIPMT 2012 Prelims
Which one of the following is not a functional unit of an ecosystem?
Not quite — the answer is A.
Stratification is the vertical layering of species, a structural feature of an ecosystem. Productivity, decomposition, energy flow and nutrient cycling are the functional aspects.
Q70AIPMT 2012 Prelims
During gamete formation, the enzyme recombinase participates during
Not quite — the answer is D.
Recombinase catalyses crossing over between non-sister chromatids of homologous chromosomes during pachytene of prophase I of meiosis. There is no crossing over in metaphase I or in meiosis II.
Q71AIPMT 2012 Prelims
Removal of RNA polymerase III from nucleoplasm will affect the synthesis of
Not quite — the answer is B.
In eukaryotes, RNA polymerase III transcribes tRNA, 5S rRNA and snRNAs, so removing it stops tRNA synthesis. RNA polymerase I makes most rRNA, and RNA polymerase II makes hnRNA (the precursor of mRNA).
Q72AIPMT 2012 Prelims
In which one of the following, the genus name, its two characters and its phylum are not correctly matched, whereas the remaining three are correct ?
Not quite — the answer is B.
Pila (apple snail) is a mollusc with a radula, but its body is unsegmented, so the pair given for it is wrong. Periplaneta (jointed appendages, chitinous exoskeleton), Asterias (spiny skin, water vascular system) and Sycon (pores, canal system) are correctly matched.
Q73AIPMT 2012 Prelims
Cirrhosis of liver is caused by the chronic intake of
Not quite — the answer is C.
Chronic heavy intake of alcohol damages liver cells and leads to cirrhosis. Cocaine, opium and chewing tobacco cause other harmful effects but are not the classic cause of cirrhosis.
Q74AIPMT 2012 Prelims
Monascus purpureus is a yeast used commercially in the production of
Not quite — the answer is A.
The yeast Monascus purpureus produces statins, which lower blood cholesterol by competitively inhibiting the enzyme that synthesises cholesterol. Streptokinase comes from Streptococcus, citric acid from Aspergillus niger and ethanol from Saccharomyces.
Q75AIPMT 2012 Prelims
The coconut water and the edible part of coconut are equivalent to
Not quite — the answer is B.
Coconut water is free-nuclear endosperm and the white edible kernel is cellular endosperm. The embryo is small, and the fibrous husk and hard shell are the mesocarp and endocarp.
Q76AIPMT 2012 Prelims
Companion cells are closely associated with
Not quite — the answer is B.
Companion cells are connected to sieve tube elements by pit fields and help maintain their pressure gradient. Guard cells surround stomata, and vessel elements belong to xylem.
Biology: not in the current NEET syllabus
These 9 questions are from topics NCERT dropped in its 2023 revision. Shown for completeness; you can skip them for NEET 2027.
9 questions. Tap an option to check your answer.
Q1AIPMT 2012 Prelims
Pheretima and its close relatives derive nourishment from
Not quite — the answer is C.
Pheretima (earthworm) is a detritivore that feeds on decaying fallen leaves and organic matter mixed with soil. It does not eat fresh leaves, sugarcane roots or soil insects.
Q2AIPMT 2012 Prelims · Q74
In an area where DDT had been used extensively, the population of birds declined significantly because
Not quite — the answer is A.
DDT accumulates through biomagnification in fish-eating birds and disturbs their calcium metabolism, so egg shells become thin and break before hatching; many eggs laid therefore did not hatch. Birds did not stop laying eggs altogether.
Q3AIPMT 2012 Prelims
Best defined function of Manganese in green plants is
Not quite — the answer is B.
Manganese is part of the water-splitting (oxygen-evolving) complex of photosystem II and is essential for photolysis of water. It does not have a primary role in water absorption, the Calvin cycle or nitrogen fixation (which needs molybdenum).
Q4AIPMT 2012 Prelims · Q83
Which one of the following is a wrong statement?
Not quite — the answer is D.
Phosphorus is a constituent of cell membranes (phospholipids), all nucleic acids and certain proteins, not all proteins, so the statement given is wrong. Nitrosomonas and Nitrobacter are chemoautotrophs, Anabaena and Nostoc fix nitrogen when free-living, and Rhizobium lives as an aerobe when free-living.
Q5AIPMT 2012 Prelims · Q89
Which one of the following is a wrong statement ?
Not quite — the answer is C.
Ozone in the upper atmosphere (stratosphere) absorbs ultraviolet radiation and protects living organisms, so calling it harmful is wrong. Eutrophication and the greenhouse effect are natural phenomena (accelerated by humans), and most forest loss has been in the tropics.
Q6AIPMT 2012 Prelims · Q112
Which part would be most suitable for raising virus-free plants for micropropagation ?
Not quite — the answer is D.
The apical and axillary meristems are free of viruses even in an infected plant, so meristem culture is used to raise virus-free plants. Nodes, bark and vascular tissue can carry the virus.
Q7AIPMT 2012 Prelims
Select the correct statement from the ones given below with respect to Periplaneta americana
Not quite — the answer is C.
Male cockroaches bear a pair of short, thread-like anal styles, which females lack. The nerve cord is ventral, food is also ground in the gizzard, and there are about 100–150 thin Malpighian tubules, not 16.
Q8AIPMT 2012 Prelims
Which one of the following is not a gaseous biogeochemical cycle in ecosystem ?
Not quite — the answer is C.
The phosphorus cycle is a sedimentary cycle with the rock reservoir and no significant gaseous phase. Carbon, nitrogen and sulphur cycles all have important atmospheric (gaseous) reservoirs.
Q9AIPMT 2012 Prelims · Q139
Anxiety and eating spicy food together in an otherwise normal human, may lead to
Not quite — the answer is B.
Anxiety and spicy food together can cause indigestion (dyspepsia), a feeling of fullness due to inadequate enzyme secretion and overeating or spicy food. Jaundice is a liver disorder, and vomiting and diarrhoea are not the usual result.
Chapter-wise split of AIPMT 2012 Prelims Biology
- Morphology of Flowering Plants7 Q
- Microbes in Human Welfare7 Q
- Human Health and Disease6 Q
- Biological Classification5 Q
- Molecular Basis of Inheritance4 Q
- Sexual Reproduction in Flowering Plants4 Q
- Anatomy of Flowering Plants4 Q
- Biotechnology: Principles and Processes4 Q
- Cell: The Unit of Life4 Q
- Evolution4 Q
- Plant Kingdom3 Q
- Chemical Coordination and Integration3 Q
- Ecosystem3 Q
- Human Reproduction3 Q
- Biomolecules2 Q
- Biodiversity and Conservation2 Q
- Body Fluids and Circulation2 Q
- Biotechnology and Its Applications1 Q
- Excretory Products and Their Elimination1 Q
- Reproductive Health1 Q
- Neural Control and Coordination1 Q
- Locomotion and Movement1 Q
- Principles of Inheritance and Variation1 Q
- Photosynthesis in Higher Plants1 Q
- Cell Cycle and Cell Division1 Q
- Animal Kingdom1 Q
About this paper
How many questions from AIPMT 2012 Prelims are on this page?
171 questions (Physics 39, Chemistry 47, Biology 85). 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 AIPMT 2012 Prelims paper, conducted by CBSE. The answer to every question was checked by the RankUp team, and the explanations are RankUp's own.
Is AIPMT 2012 Prelims useful for NEET 2027?
Yes. The NEET syllabus is built on the same NCERT books. 23 questions here are on topics NCERT has since dropped; they are listed separately so you can skip them.
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