Quick key All 180 answers 001 B
002 B
003 B
004 C
005 C
006 B
007 C
008 B
009 B
010 C
011 C
012 B
013 B
014 B
015 D
016 B
017 B
018 C
019 B
020 B
021 B
022 B
023 B
024 B
025 A
026 B
027 B
028 C
029 B
030 C
031 B
032 C
033 C
034 C
035 B
036 B
037 D
038 B
039 B
040 B
041 B
042 B
043 C
044 C
045 B
046 C
047 B
048 D
049 C
050 B
051 B
052 C
053 B
054 B
055 B
056 C
057 C
058 B
059 B
060 B
061 C
062 C
063 B
064 A
065 C
066 D
067 C
068 B
069 C
070 B
071 B
072 B
073 B
074 B
075 C
076 B
077 B
078 A
079 B
080 C
081 B
082 B
083 B
084 B
085 C
086 A
087 B
088 B
089 B
090 B
091 B
092 D
093 B
094 B
095 B
096 B
097 B
098 B
099 C
100 B
101 B
102 D
103 B
104 B
105 A
106 B
107 C
108 B
109 C
110 B
111 A
112 B
113 B
114 B
115 B
116 C
117 A
118 C
119 B
120 B
121 A
122 B
123 B
124 C
125 A
126 A
127 B
128 C
129 B
130 D
131 B
132 B
133 B
134 D
135 C
136 A
137 B
138 C
139 B
140 C
141 B
142 B
143 B
144 C
145 B
146 C
147 B
148 B
149 B
150 B
151 C
152 B
153 C
154 B
155 B
156 B
157 B
158 B
159 A
160 B
161 B
162 D
163 B
164 C
165 A
166 B
167 B
168 B
169 C
170 B
171 B
172 D
173 B
174 A
175 B
176 B
177 B
178 B
179 C
180 B
Physics Section A · worked reasoning Q001 (B) Torque and work
Both torque and work have dimensions [ML²T⁻²].
Units & Dimensions
Q002 (B) 3
Leading zeros are not significant; the trailing zero after the decimal is. So 2, 5, 0 = 3.
Errors & Significant Figures
Q003 (B) 1 : 3 : 5
sₙ = (a/2)(2n − 1) gives 1 : 3 : 5.
Kinematics
Q004 (C) 35 m
s₄ = (g/2)(2×4 − 1) = 5 × 7 = 35 m.
Kinematics
Q005 (C) 6 N s
Impulse = Δp = m(v − (−v)) = 0.15 × 40 = 6 N s.
Laws of Motion
Q006 (B) 4 N
a = 10/5 = 2 m s⁻²; T accelerates the 2 kg block ⇒ T = 2 × 2 = 4 N.
Laws of Motion
Q007 (C) 4000 N
F = KE/d = (½ × 0.01 × 400²)/0.2 = 800/0.2 = 4000 N.
Work, Energy & Power
Q008 (B) 2 rad s⁻²
α = τ/I = 4/2 = 2 rad s⁻².
Rotational Motion
Q009 (B) √(2/5) R
I = (2/5)MR² = MK² ⇒ K = √(2/5) R.
Rotational Motion
Q010 (C) Angular velocity increases
I decreases and L = Iω is conserved, so ω increases.
Rotational Motion
Q011 (C) 22.4 km s⁻¹
v_e = R√(8πGρ/3) ∝ R at constant density, so it doubles.
Gravitation
Q012 (B) Angular momentum
The gravitational force is central, so torque about the sun is zero and L stays constant.
Gravitation
Q013 (B) ½ × stress × strain
Energy density = ½ × stress × strain = ½ × Y × strain².
Elasticity
Q014 (B) Four times
v_t ∝ r², so doubling r makes it four times.
Fluids
Q015 (D) 16 times
Stefan's law: E ∝ T⁴, so 2⁴ = 16 times.
Thermal Properties
Q016 (B) nRT ln(V₂/V₁)
For isothermal work, W = ∫P dV = nRT ln(V₂/V₁).
Thermodynamics
Q017 (B) Zero
Internal energy is a state function; over a complete cycle ΔU = 0 and Q = W.
Thermodynamics
Q018 (C) Absolute temperature
Average KE = (3/2)kT, independent of the nature of the gas.
Kinetic Theory
Q019 (B) Decreases
Effective g becomes (g + a), and T = 2π√(l/g_eff) decreases.
Oscillations
Q020 (B) At the extreme positions
a = −ω²x is largest in magnitude where |x| = A.
Oscillations
Q021 (B) 4
Beat frequency = |f₁ − f₂| = 4 Hz.
Waves
Q022 (B) Twice
n ∝ √T, so a fourfold tension doubles the frequency.
Waves
Q023 (B) K times smaller
F_medium = F_vacuum/K.
Electrostatics
Q024 (B) Zero
Potential difference is zero along an equipotential surface, so W = qΔV = 0.
Electrostatics
Q025 (A) 1 μF
1/C = 3/3 ⇒ C = 1 μF.
Capacitors
Q026 (B) Decreases
More charge carriers are thermally generated, so resistivity falls.
Current Electricity
Q027 (B) 0.8 A
E_eq = 2 V, r_eq = 0.5 Ω ⇒ I = 2/(2 + 0.5) = 0.8 A.
Current Electricity
Q028 (C) 4R
Volume constant: R ∝ l², so R' = 4R.
Current Electricity
Q029 (B) Zero force
F = qvB sinθ = 0 when θ = 0°.
Moving Charges & Magnetism
Q030 (C) Independent of speed
T = 2πm/qB contains no velocity term.
Moving Charges & Magnetism
Q031 (B) Parallel to B
τ = NIAB sinθ where θ is between the normal and B; maximum when the plane contains B.
Moving Charges & Magnetism
Q032 (C) Is inversely proportional to absolute temperature
χ = C/T for paramagnets.
Magnetism & Matter
Q033 (C) Energy
The induced effect opposes the change, so work must be done — energy is conserved.
Electromagnetic Induction
Q034 (C) 10 V
ε = M dI/dt = 0.5 × 20 = 10 V.
Electromagnetic Induction
Q035 (B) 2.83 A
I_rms = I₀/√2 = 4/1.414 = 2.83 A.
Alternating Current
Q036 (B) Zero
Current lags voltage by 90°, so cosφ = 0 and average power is zero.
Alternating Current
Q037 (D) Radio waves
Radio waves occupy the long-wavelength, low-frequency end of the spectrum.
Electromagnetic Waves
Q038 (B) Real, inverted and of the same size
For u = 2f, v = 2f and m = −1.
Ray Optics
Q039 (B) 9 cm
Apparent depth = real depth/μ = 12 × 3/4 = 9 cm.
Ray Optics
Q040 (B) Coherent with a constant phase difference
A constant phase relationship is essential for a stable fringe pattern.
Wave Optics
Q041 (B) 2λ/a
The first minima lie at sinθ = ±λ/a, so the full angular width is 2λ/a.
Wave Optics
Q042 (B) 620 nm
λ₀ = 1240/φ(eV) nm = 1240/2 = 620 nm.
Dual Nature of Matter
Q043 (C) 1/8
N = N₀(1/2)³ = N₀/8.
Nuclei
Q044 (C) 4.77 Å
rₙ = 0.53 n² Å = 0.53 × 9 = 4.77 Å.
Atoms
Q045 (B) Reverse bias beyond the breakdown voltage
In the Zener breakdown region the voltage stays constant while current varies.
Semiconductors
Chemistry Section B · worked reasoning Q046 (C) 2.0
Each molecule has 4 O atoms ⇒ 0.5 × 4 = 2 mol of oxygen atoms.
Some Basic Concepts
Q047 (B) 1.33 mol
H₂ is limiting: 2 mol H₂ × (2 NH₃/3 H₂) = 1.33 mol.
Some Basic Concepts
Q048 (D) 4.761 Å
rₙ = 0.529 n² Å = 0.529 × 9 = 4.761 Å.
Structure of Atom
Q049 (C) n = 3, l = 3, m = +1
l can take values 0 to (n − 1), so l = 3 is impossible when n = 3.
Structure of Atom
Q050 (B) Cl
Small size and high electron–electron repulsion in F make Cl's value the most negative.
Classification & Periodicity
Q051 (B) Group 15, period 3
Five valence electrons in the third shell ⇒ group 15, period 3.
Classification & Periodicity
Q052 (C) T-shaped
sp³d with three bond pairs and two lone pairs in equatorial positions gives a T-shape.
Chemical Bonding
Q053 (B) Intermolecular hydrogen bonding
Strong H-bonding between HF molecules requires extra energy to break.
Chemical Bonding
Q054 (B) sp² hybridised
Each carbon forms three sigma bonds and one pi bond ⇒ sp².
Chemical Bonding
Q055 (B) BF₃ > NH₃ > H₂O
BF₃ 120°, NH₃ 107°, H₂O 104.5° — lone pairs progressively compress the angle.
Chemical Bonding
Q056 (C) Zero
By convention ΔfH° of an element in its reference state is zero.
Thermodynamics
Q057 (C) Temperature
Intensive properties do not depend on the amount of substance.
Thermodynamics
Q058 (B) Shifts the equilibrium forward
Le Chatelier: the system shifts towards the side with fewer gaseous moles.
Equilibrium
Q059 (B) Common ion effect
Added Cl⁻ suppresses the dissociation equilibrium of AgCl.
Equilibrium
Q060 (B) HPO₄²⁻
A conjugate base is formed by removing one proton.
Equilibrium
Q061 (C) Disproportionation
Chlorine goes from 0 to −1 and to +1 simultaneously.
Redox Reactions
Q062 (C) –NO₂
The nitro group withdraws electrons by both –I and –R effects.
Organic Chemistry – Basic Principles
Q063 (B) 3
n-Pentane, isopentane and neopentane.
Organic Chemistry – Basic Principles
Q064 (A) Simple distillation
Simple distillation suffices when boiling points differ appreciably and neither decomposes.
Organic Chemistry – Basic Principles
Q065 (C) n-Butane
Two ethyl units couple to give a symmetrical alkane with four carbons.
Hydrocarbons
Q066 (D) But-1-yne
Only terminal alkynes have an acidic sp C–H hydrogen.
Hydrocarbons
Q067 (C) Nitrobenzene
The strongly deactivating nitro group also forms a complex with AlCl₃.
Hydrocarbons
Q068 (B) Mole fraction of solute
Raoult's law for a non-volatile solute: (P° − P)/P° = x₂.
Solutions
Q069 (C) Calcium chloride
π = iCRT and CaCl₂ has the highest van't Hoff factor, i = 3.
Solutions
Q070 (B) Can displace hydrogen from dilute acids
Metals with negative standard reduction potentials are stronger reducing agents than H₂.
Electrochemistry
Q071 (B) The number of ions per unit volume decreases
Conductivity is measured per unit volume, which now contains fewer ions.
Electrochemistry
Q072 (B) Order can be zero or fractional
Order is experimental and may be fractional or zero; molecularity is a whole number ≥ 1.
Chemical Kinetics
Q073 (B) A straight line with negative slope
[A] = [A]₀ − kt, a straight line of slope −k.
Chemical Kinetics
Q074 (B) Providing an alternative path of lower activation energy
The catalyst lowers Ea; ΔH and K remain unchanged.
Chemical Kinetics
Q075 (C) +6
x + 4(−2) = −2 ⇒ x = +6.
d- and f-Block Elements
Q076 (B) Cr²⁺
Cr²⁺ readily loses an electron to attain the stable half-filled t₂g³ configuration of Cr³⁺.
d- and f-Block Elements
Q077 (B) Hard and chemically inert with high melting points
Small atoms trapped in the lattice make the compounds hard, high melting and inert.
d- and f-Block Elements
Q078 (A) [Pt(NH₃)₂Cl₂]
The square planar MA₂B₂ complex exists as cis (cisplatin) and trans forms.
Coordination Compounds
Q079 (B) Square planar and diamagnetic
Strong-field CN⁻ pairs the 3d⁸ electrons, giving dsp² square planar with no unpaired electrons.
Coordination Compounds
Q080 (C) Hexadentate ligand
EDTA binds through two nitrogen and four oxygen donor atoms.
Coordination Compounds
Q081 (B) But-2-ene
Saytzeff's rule favours the more substituted, more stable alkene.
Haloalkanes & Haloarenes
Q082 (B) The C–Cl bond has partial double bond character due to resonance
Resonance shortens and strengthens the C–Cl bond, making displacement difficult.
Haloalkanes & Haloarenes
Q083 (B) 3° > 2° > 1°
The reaction is E1 and follows carbocation stability.
Alcohols, Phenols & Ethers
Q084 (B) Methyl bromide and sodium tert-butoxide
The SN2 step needs an unhindered primary halide, so the bulky group must come from the alkoxide.
Alcohols, Phenols & Ethers
Q085 (C) Methanal
Only aldehydes without an α-hydrogen disproportionate in concentrated alkali.
Aldehydes, Ketones & Carboxylic Acids
Q086 (A) Aldehydes and ketones
Aldehydes reduce Tollens' reagent to give a silver mirror; ketones do not.
Aldehydes, Ketones & Carboxylic Acids
Q087 (B) α-carbon
Carboxylic acids with an α-hydrogen are halogenated at the α-position using X₂/red P.
Aldehydes, Ketones & Carboxylic Acids
Q088 (B) Distinguish primary, secondary and tertiary amines
Benzenesulphonyl chloride gives an alkali-soluble product with 1°, an insoluble one with 2°, and no reaction with 3° amines.
Amines
Q089 (B) Benzenediazonium chloride
Diazotisation must be carried out at low temperature to keep the diazonium salt stable.
Amines
Q090 (B) Hydrogen bonds
Hydrogen bonds between backbone C=O and N–H groups hold the α-helix and β-sheet.
Biomolecules
Botany Section C · worked reasoning Q091 (B) Contrasting characters arranged in couplets
Each step of a key offers a couplet of contrasting statements, one of which is accepted.
The Living World
Q092 (D) Habitat and geographical range
The criteria were cell structure, thallus organisation, nutrition, reproduction and phylogeny.
Biological Classification
Q093 (B) Archaebacteria
Archaebacteria have a distinctive cell wall that allows them to live in extreme habitats.
Biological Classification
Q094 (B) Consist of free RNA without a protein coat
T. O. Diener discovered viroids as free RNA of low molecular weight causing potato spindle tuber disease.
Biological Classification
Q095 (B) Live on land but need water for sexual reproduction
Their motile antherozoids require a film of water to reach the archegonium.
Plant Kingdom
Q096 (B) Nitrogen-fixing cyanobacteria
Coralloid roots harbour nitrogen-fixing cyanobacteria such as Anabaena.
Plant Kingdom
Q097 (B) Rhizophora
Mangrove plants develop negatively geotropic breathing roots in marshy soil.
Morphology of Flowering Plants
Q098 (B) The main axis continuing to grow with flowers borne laterally in acropetal order
In racemose types the growth of the main axis is indefinite.
Morphology of Flowering Plants
Q099 (C) Drupe
Drupes develop from monocarpellary superior ovaries with a stony endocarp.
Morphology of Flowering Plants
Q100 (B) Alternating formation of spring wood and autumn wood
Seasonal variation in cambial activity gives light spring wood and dark autumn wood.
Anatomy of Flowering Plants
Q101 (B) Dumb-bell shaped
Monocot grasses have dumb-bell shaped guard cells; dicots have bean-shaped ones.
Anatomy of Flowering Plants
Q102 (D) Xylem parenchyma
Xylem parenchyma is the only living component; it stores food and helps in radial conduction.
Anatomy of Flowering Plants
Q103 (B) Singer and Nicolson
Singer and Nicolson (1972) described lipids as a fluid bilayer with proteins floating in it.
Cell: The Unit of Life
Q104 (B) Ribosomal RNA synthesis
The nucleolus is a non-membrane-bound region actively synthesising rRNA.
Cell: The Unit of Life
Q105 (A) Stacks of thylakoids
Each granum is a stack of disc-shaped thylakoids where light reactions occur.
Cell: The Unit of Life
Q106 (B) A zwitterion
Both the amino and carboxyl groups are ionised, giving a dipolar zwitterion.
Biomolecules
Q107 (C) Phosphate group
Nucleoside = base + sugar; nucleotide = base + sugar + phosphate.
Biomolecules
Q108 (B) S phase
DNA content doubles during the synthesis phase while chromosome number stays the same.
Cell Cycle & Cell Division
Q109 (C) Anaphase
Sister chromatids separate and are pulled poleward in anaphase.
Cell Cycle & Cell Division
Q110 (B) Water
Hill showed isolated chloroplasts evolve O₂ in the presence of an electron acceptor, without CO₂.
Photosynthesis
Q111 (A) A proton gradient across the thylakoid membrane
Protons accumulate in the thylakoid lumen and flow out through ATP synthase.
Photosynthesis
Q112 (B) The rate is determined by the factor present in the smallest amount
The pace of the process is set by the factor nearest its minimum value.
Photosynthesis
Q113 (B) A lower CO₂ compensation point and no photorespiration
The C₄ pump concentrates CO₂ in bundle sheath cells, so photorespiration is negligible.
Photosynthesis
Q114 (B) Cytoplasm
The EMP pathway is entirely cytoplasmic and yields a net gain of 2 ATP.
Respiration in Plants
Q115 (B) Mitochondrial matrix
Pyruvate dehydrogenase acts in the matrix, releasing CO₂ and reducing NAD⁺.
Respiration in Plants
Q116 (C) Cytokinin
Cytokinins promote cell division and delay ageing of leaves.
Plant Growth & Development
Q117 (A) Ethylene
Ethylene, a gaseous hormone, hastens ripening, senescence and abscission.
Plant Growth & Development
Q118 (C) Sporopollenin
Sporopollenin resists high temperature and enzymes, so pollen fossilises well.
Sexual Reproduction in Flowering Plants
Q119 (B) Geitonogamy
Geitonogamy is functionally cross pollination but genetically similar to autogamy.
Sexual Reproduction in Flowering Plants
Q120 (B) Self-incompatibility
Self-incompatibility prevents pollen from germinating on the stigma of the same flower.
Sexual Reproduction in Flowering Plants
Q121 (A) Perisperm
Black pepper and beet retain perisperm in the mature seed.
Sexual Reproduction in Flowering Plants
Q122 (B) 1 : 2 : 1
Incomplete dominance makes the genotypic and phenotypic ratios identical.
Principles of Inheritance
Q123 (B) Morgan in Drosophila
Morgan found that genes on the same chromosome do not assort independently.
Principles of Inheritance
Q124 (C) X-linked recessive
A carrier female transmits the trait to half her sons.
Principles of Inheritance
Q125 (A) A and B only
Offspring receive I^A or I^B from one parent and i from the other, giving group A or B.
Principles of Inheritance
Q126 (A) 10 bp and 3.4 nm
Each turn spans 3.4 nm and contains about 10 base pairs 0.34 nm apart.
Molecular Basis of Inheritance
Q127 (B) A promoter, structural gene and terminator
The promoter and terminator flank the structural gene and define the unit.
Molecular Basis of Inheritance
Q128 (C) It is overlapping
The code is non-overlapping; each base belongs to only one codon.
Molecular Basis of Inheritance
Q129 (B) Repetitive satellite DNA (VNTR)
Variable number tandem repeats show high degrees of polymorphism between individuals.
Molecular Basis of Inheritance
Q130 (D) Body weight of an individual
Populations have statistical attributes; body weight is an individual character.
Organisms & Populations
Q131 (B) Intrinsic rate of natural increase
r is the difference between per capita birth and death rates.
Organisms & Populations
Q132 (B) Fragmentation, leaching, catabolism, humification, mineralisation
Detritivores fragment the detritus first; humus is finally mineralised to release nutrients.
Ecosystem
Q133 (B) Lichens
Lichens secrete acids that weather the rock and build the first soil.
Ecosystem
Q134 (D) Ex situ conservation
The fourth member of the quartet is co-extinction, not conservation.
Biodiversity & Conservation
Q135 (C) 8.1%
India is one of the twelve mega-diversity countries with about 8.1% of global species.
Biodiversity & Conservation
Zoology Section D · worked reasoning Q136 (A) Porifera
Flagellated collar cells line the spongocoel and generate the water current in sponges.
Animal Kingdom
Q137 (B) Cnidarians
Cnidoblasts on the tentacles of cnidarians contain stinging nematocysts.
Animal Kingdom
Q138 (C) Annelida
The annelid body is divided into similar segments both externally and internally.
Animal Kingdom
Q139 (B) An air bladder
Without a swim bladder, Chondrichthyes would sink if they stopped swimming.
Animal Kingdom
Q140 (C) Cardiac muscle
These communication junctions let cardiac fibres contract as a single unit.
Structural Organisation in Animals
Q141 (B) Biting and chewing type
The cockroach has a labrum, mandibles, maxillae, labium and hypopharynx for chewing.
Structural Organisation in Animals
Q142 (B) The diaphragm contracts and thoracic volume increases
Contraction of the diaphragm and external intercostals enlarges the thorax and lowers intrapulmonary pressure.
Breathing & Exchange of Gases
Q143 (B) Damage to alveolar walls reducing the respiratory surface
Cigarette smoking is a major cause; alveolar walls break down and gas exchange area falls.
Breathing & Exchange of Gases
Q144 (C) 104 mm Hg
Alveolar pO₂ is 104 mm Hg against 40 mm Hg in deoxygenated blood, driving diffusion.
Breathing & Exchange of Gases
Q145 (B) Ventricular depolarisation
The P wave is atrial depolarisation, QRS ventricular depolarisation and T ventricular repolarisation.
Body Fluids & Circulation
Q146 (C) All blood groups
Group O red cells carry neither A nor B antigen, so O is the universal donor.
Body Fluids & Circulation
Q147 (B) Lacking RBCs and large plasma proteins
Lymph is a colourless fluid with lymphocytes but no erythrocytes or large proteins.
Body Fluids & Circulation
Q148 (B) 125 mL per minute
125 mL per minute amounts to about 180 litres of filtrate per day.
Excretory Products
Q149 (B) Juxtaglomerular apparatus
A fall in glomerular blood flow stimulates the JGA to release renin.
Excretory Products
Q150 (B) The loop of Henle and vasa recta
Their parallel, oppositely flowing arrangement maintains the medullary osmotic gradient.
Excretory Products
Q151 (C) A band
The A band, corresponding to the myosin filament, retains its length.
Locomotion & Movement
Q152 (B) An autoimmune disorder affecting the neuromuscular junction
Autoantibodies block neuromuscular transmission, causing fatigue and muscle weakness.
Locomotion & Movement
Q153 (C) Ball and socket joint
The shoulder joint permits movement in all planes.
Locomotion & Movement
Q154 (B) Release of neurotransmitter by fusion of synaptic vesicles with the presynaptic membrane
Ca²⁺ influx triggers exocytosis of the transmitter into the synaptic cleft.
Neural Control & Coordination
Q155 (B) Dura mater, arachnoid, pia mater
The tough dura lies outermost and the delicate pia adheres to the brain surface.
Neural Control & Coordination
Q156 (B) Rod cells
Rods contain rhodopsin, a derivative of vitamin A, and function in dim light.
Neural Control & Coordination
Q157 (B) Iodine
Without iodine the thyroid cannot make T₃ and T₄, and the gland enlarges.
Chemical Coordination
Q158 (B) Binding to membrane receptors and generating second messengers such as cAMP
Their receptors are on the cell surface; steroid hormones instead enter the cell.
Chemical Coordination
Q159 (A) Differentiation of T lymphocytes
The thymus secretes thymosin, promoting cell-mediated immunity and antibody production.
Chemical Coordination
Q160 (B) Spermiogenesis
Spermiation is the later release of sperms from the Sertoli cells into the lumen.
Human Reproduction
Q161 (B) A surge of LH
The LH surge around day 14 causes rupture of the Graafian follicle.
Human Reproduction
Q162 (D) Follicle stimulating hormone
FSH is a gonadotropin from the anterior pituitary.
Human Reproduction
Q163 (B) Trophoblast
The outer trophoblast layer makes contact with the endometrium during implantation.
Human Reproduction
Q164 (C) Determining the sex of the foetus
The statutory ban aims to prevent female foeticide.
Reproductive Health
Q165 (A) Six months after parturition
Ovulation and the menstrual cycle usually do not occur during intense lactation up to six months.
Reproductive Health
Q166 (B) A non-steroidal oral pill taken once a week
Developed at CDRI Lucknow, it has few side effects and high contraceptive value.
Reproductive Health
Q167 (B) Chemical evolution of life
Electric discharge in a reducing atmosphere of CH₄, NH₃, H₂ and water vapour produced amino acids.
Evolution
Q168 (B) Adaptive radiation
From one seed-eating ancestor many beak forms evolved to exploit different niches.
Evolution
Q169 (C) Reptiles and birds
It had feathers and a beak like a bird but teeth and a long tail like a reptile.
Evolution
Q170 (B) Homology and divergent evolution
The same basic anatomical plan is adapted to different functions.
Evolution
Q171 (B) Contaminated water, vegetables and soil carrying eggs
Eggs passed in faeces contaminate soil and water and are ingested.
Human Health & Disease
Q172 (D) Antibody production against a specific antigen
Antigen-specific antibody responses belong to acquired immunity.
Human Health & Disease
Q173 (B) IgA
Colostrum secreted during the first days of lactation is rich in IgA.
Human Health & Disease
Q174 (A) Metastasis
Metastasis is the most feared property of malignant tumours.
Human Health & Disease
Q175 (B) Cannabis sativa
Flower tops, leaves and resin of Cannabis sativa yield marijuana, hashish and ganja.
Human Health & Disease
Q176 (B) Anode, because DNA is negatively charged
The phosphate backbone makes DNA negatively charged.
Biotechnology – Principles
Q177 (B) Ethidium bromide and exposure to UV radiation
Bright orange bands appear under UV light after ethidium bromide staining.
Biotechnology – Principles
Q178 (B) Sparged stirred tank bioreactor
Sparging supplies air without shearing, giving better oxygen transfer than a simple stirrer.
Biotechnology – Principles
Q179 (C) Provitamin A (β-carotene)
It was engineered to combat vitamin A deficiency.
Biotechnology – Applications
Q180 (B) Producing A and B chains separately in E. coli and joining them by disulphide bonds
The two chains were produced separately and then combined to form functional human insulin.
Biotechnology – Applications
Set 2 answer key · Re-work every wrong answer · End of key