## Gate life science previous year question paper 2021

Gate life science previous year question paper:- GATE 2023 exam will be conducted in online mode from February 4, 5, 11 and 12. To analysis the question of Gate life science question paper from 2007 to 2022. In Below there are last 16 years of gate life science previous year question paper available in PDF.

1. The movie was funny and I _.

(A) could help laughing.
(B) couldn’t help laughed.
(C) couldn’t help laughing.
(D) could help laughed.

(A) 0.75
(B) 1.25
(C) 2.25
(D) 3.25

3. Both the numerator and the denominator of 3/4 are increased by a positive integer, 𝑥, and those of 15/17 are decreased by the same integer. This operation results in the same value for both the fractions. What is the value of 𝑥?
(A) 1
(B) 2
(C) 3
(D) 4

Q.4 A survey of 450 students about their subjects of interest resulted in the
following outcome.

• 150 students are interested in Mathematics.
• 200 students are interested in Physics.
• 175 students are interested in Chemistry.
• 50 students are interested in Mathematics and Physics.
• 60 students are interested in Physics and Chemistry.
• 40 students are interested in Mathematics and Chemistry.
• 30 students are interested in Mathematics, Physics and Chemistry.
• Remaining students are interested in Humanities.

Based on the above information, the number of students interested in
Humanities is
(A) 10
(B) 30
(C) 40
(D) 45

Q.5 For the picture shown above, which one of the following is the correct picture
representing reflection with respect to the mirror shown as the dotted line?

## Q. 6 – Q. 10 Carry TWO marks each.

6. In the last few years, several new shopping malls were opened in the city. The total number of visitors in the malls is impressive. However, the total revenue generated through sales in the shops in these malls is generally low.

Which one of the following is the CORRECT logical inference based on the
information in the above passage?

(A) Fewer people are visiting the malls but spending more.
(B) More people are visiting the malls but not spending enough.
(C) More people are visiting the malls and spending more.
(D) Fewer people are visiting the malls and not spending enough.

GATE 2022 Life Sciences XL

Q.7 In a partnership business, the monthly investment by three friends for the first six months is in the ratio 3: 4: 5. After six months, they had to increase their monthly investments by 10%, 15% and 20%, respectively, of their initial monthly investment. The new investment ratio was kept constant for the next six months.

What is the ratio of their shares in the total profit (in the same order) at the end of the year such that the share is proportional to their individual total investment over the year?

(A) 22 : 23 : 24
(B) 22 : 33 : 50
(C) 33 : 46 : 60
(D) 63 : 86 : 110

Q.8 Consider the following equations of straight lines:
Line L1: 2𝑥 − 3𝑦 = 5
Line L2: 3𝑥 + 2𝑦 = 8
Line L3: 4𝑥 − 6𝑦 = 5
Line L4: 6𝑥 − 9𝑦 = 6

Which one among the following is the correct statement?

(A) L1 is parallel to L2 and L1 is perpendicular to L3.
(B) L2 is parallel to L4 and L2 is perpendicular to L1.
(C) L3 is perpendicular to L4 and L3 is parallel to L2.
(D) L4 is perpendicular to L2 and L4 is parallel to L3.

Q.9 Given below are two statements and four conclusions drawn based on the statements.

Statement 1: Some soaps are clean.
Statement 2: All clean objects are wet.
Conclusion I: Some clean objects are soaps.
Conclusion II: No clean object is a soap.
Conclusion III: Some wet objects are soaps.
Conclusion IV: All wet objects are soaps.

Which one of the following options can be logically inferred?
(A) Only conclusion I is correct.
(B) Either conclusion I or conclusion II is correct.
(C) Either conclusion III or conclusion IV is correct.
(D) Only conclusion I and conclusion III are correct.

Q.10. An ant walks in a straight line on a plane, leaving behind a trace of its movement. The initial position of the ant is at point P facing east. The ant first turns 72o anticlockwise at P, and then does the following two steps in sequence exactly FIVE times before halting.

Q.11 Consider a second order reaction, 2A ————> Product.

The concentration of A is represented as [A].
Which of the following is the CORRECT plot for determining the rate constant for
the above reaction?

Q. 12 Which among the following has the least second ionization energy?

(A) Al
(B) Si
(C) P
(D) S

Q.13 Which among the following metal ions has the highest enthalpy of hydration? (Assume the given metal ions have the same counter ion.)
Given: Atomic numbers of Ti, V, Cr and Mn are 22, 23, 24 and 25, respectively.

(A) Ti2+
(B) V2+
(C) Cr2+
(D) Mn2+

Q.14 Among the following, the one having the smallest bond angle is

(A) PH3
(B) PF3
(C) NF3
(D) NH3

Q.15 Which of the following is the CORRECT statement about hexoses?

(A) D-mannose is C-4 epimer of D-glucose.
(B) D-galactose is C-2 epimer of D-glucose.
(C) D-glucose and L-glucose are diastereomers.
(D) D-glucose and D-galactose are diastereomers.

Q.16 The bases present in DNA are

(A) adenine, cytosine, guanine and thymine.
(B) adenine, guanine, thymine and uracil.
(C) adenine, cytosine, thymine and uracil.
(D) cytosine, guanine, thymine and uracil.

Q.17 The CORRECT order of basicity for the following compounds is

(A) I > II > III.
(B) II > III > I.
(C) II > I > III.
(D) III > I > II.

Q.18 Molar conductance of monobromoacetic acid at infinite dilution is calculated to be
x × 10-4S m2 mol–1 at 25 oC.
The value of x is (round off to the nearest integer)
Given:

(A) 164
(B) 195
(C) 389
(D) 467

Q.19 A sample of benzene, contaminated with a non-volatile and non-ionic solute, boils at 0.31°C higher than that of pure benzene. The molality of the solute in the contaminated solution is __ (round off to two decimal places).
Given:

Gas constant = 8.314 J K1 mol1

Molecular weight of benzene is 78.11 g mol1

Normal boiling point of benzene is 80.1 °C
Enthalpy of vaporization of benzene is 30.76 kJ mol1

## Q.20 – Q.27 Carry TWO marks Each

Q.20 Among the following statements about cobalt complexes, which is/are CORRECT?
Given: Atomic number of Co is 27

(A) [Co(NH3)4] 2+ exhibits square planar geometry.
(B) [Co(en)3] 3+ does not show optical isomerism (en = ethylenediamine).
(C) [Co(H2O)6] 3+ is paramagnetic in nature.
(D) [Co(NH3)5Cl)]2+ shows ligand-to-metal charge transfer.

Q.21 Consider the following reaction:

The CORRECT statement(s) related to mono-chlorination at carbon-2 position
is/are

(A) The reaction proceeds through an alkyl radical intermediate.
(B) Complete inversion of configuration at carbon-2 takes place.
(C) Complete retention of configuration at carbon-2 takes place.
(D) A mixture of enantiomers is formed.

Q.22 Consider the following enzyme catalyzed reaction:

Where E is enzyme, S is substrate, ES is enzyme-substrate complex and P is product.

The CORRECT statement(s) for the above reaction is/are

(A) Maximum possible rate of product formation is dependent on k2 and initial concentration of enzyme.
(B) For a low substrate concentration, the rate of product formation is first order with respect to enzyme and also first order with respect to the substrate.
(C) The rate of product formation is independent of the concentration of enzymesubstrate complex.
(D) For a very high substrate concentration, initial rate of product formation is zero order with respect to the substrate.

Q.23 Consider the following reaction:

The CORRECT pathway(s) involved in the reaction is/are

(A) E2 followed by isomerization
(B) E1 followed by isomerization
(C) SN1 followed by isomerization
(D) Isomerization through carbocation

Q.24 An aqueous solution of aspirin (HA) is prepared at pH 7.4. The ratio of concentration of A and HA at equilibrium is __ (round off to the nearest integer).
Given: Ka of aspirin is 3.98 × 10-4 .

Q.25 The total number of 3-centre-2-electron bonds in B4H10 is __ (in integer).

Q.26 The equilibrium constant for isomerization of 1-butene to trans-2-butene at 27 oC
is __ (round off to one decimal place).
Given: Gas constant = 8.314 J K–1 mol–1

ΔfG0 of 1-butene = +71.39 kJ mol–1.

ΔfGo of trans-2-butene = +63.06 kJ mol–1.

Q.27 A 16 mW monochromatic light emits 4×1016 photons in 1 second. When this light incidents on a metal strip, photoelectrons are emitted. The wavelength of the emitted photoelectrons (in Å) is __ (round off to one decimal place).
Given: Work function of the metal = 2.0 eV
Charge of an electron = 1.6 × 10–19 C
Mass of an electron = 9.1 × 1031 kg
Planck’s constant = 6.626 × 10–34 J s

## Biochemistry XL (Q): Q.28 – Q.35 Carry ONE mark Each

Q.28 Which of the immune cells listed below are agranular?
P. Eosinophils
Q. Mast cells
R. Monocytes
S. T-cells

(A) P and Q only
(B) Q and R only
(C) R and S only
(D) S and P only

Q.29 Which one of the following enzymes is located in the outer mitochondrial membrane?
(A) Citrate synthase
(B) Fumarase
(C) Monoamine oxidase
(D) Succinate dehydrogenase

Q.30 Which one of the following statements about the DNA polymerase III of E. coli is NOT correct?
(A) It catalyzes nick translation.
(B) Its absence is lethal to E. coli.
(C) It synthesizes a complementary DNA strand using a single-stranded template.
(D) It possesses 3′ → 5′ exonuclease activity.

Q.31 Which one of the following compounds is NOT a translation inhibitor?
(A) Chloramphenicol
(B) Cycloheximide
(C) Puromycin
(D) Rifampicin

Q.32 A dye was allowed to undergo migration on a chromatographic paper using a solvent. The dye, and the solvent-front migrated 5 and 20 𝑐𝑚, respectively, from the point of origin. The retention factor (rounded off to two places of decimals) for the dye is _.

Q.33 The 𝑝𝐾௔ values of the carboxylic and amino groups of an amino acid with a non-ionizable side chain are 2.17 and 9.13, respectively. The isoelectric point (rounded off to two places of decimals) of this amino acid is _.

Q.34 The number of ATP molecules required for the complete assimilation of one molecule of CO2 in Calvin cycle is _.

Q.35 The absorbance of a 5 × 10ିସ 𝑀 solution of tyrosine at 280 𝑛𝑚 wavelength is 0.75. The path length of the cuvette is 1 𝑐𝑚. The molar absorption coefficient at the given wavelength in M-1 cm-1, correct to the nearest integer, is _.

## Q.36 – Q.46 Carry TWO marks Each

Q.36 Filamentous photosynthetic algae were placed on a microscopic slide and illuminated with light of different colors as illustrated.

The bacteria that are known to migrate towards the region of high o2 were also added uniformly on the slide. Which one of the following options illustrates the
distribution of bacteria along the length of the microscopic slide after illumination?

Q.37 Two RNAs shown below were used separately as templates in an in vitro translation system, which can generate proteins in all possible reading frames.
𝑅𝑁𝐴1: 5′ − (𝐴𝐺)n − 3′
𝑅𝑁𝐴2: 5′ − (𝐴𝐴𝐺)n − 3′
The 𝑅𝑁𝐴1 translated product contained Arg and Glu.
The 𝑅𝑁𝐴2 translated product contained Arg, Glu, and Lys.

Which one of the following codons directs the incorporation of Arg?
(A) AAG
(B) AGA
(C) GAA
(D) GAG

Q.38 Which of the following statements about endogenous synthesis of insulin are correct?
P. Insulin is synthesized as preproinsulin.
Q. Preproinsulin is converted to proinsulin.
R. Single-site cleavage of proinsulin eliminates C chain.
S. Mature insulin consists of disulphide-linked A and B chains.

(A) P, Q, and R
(B) P, Q, and S
(C) P, R, and S
(D) Q, R, and S

Q.39 Which one of the following enzymes converts testosterone to estradiol?
(A) Aromatase
(B) 3β-hydroxysteroid dehydrogenase
(C) 5α-reductase
(D) 17β-hydroxysteroid dehydrogenase

Q.40 Purification of 6×His-tagged protein using Ni-NTA column is an example of __
(A) affinity chromatography
(B) hydrophobic-interaction chromatography
(C) ion-exchange chromatography
(D) size-exclusion chromatography

Q.41 Which of the following carbohydrates has/have a 𝛽1 → 4 glycosidic linkage?
(A) Cellulose
(B) Chitin
(C) Lactose
(D) Maltose

Q.42 Which of the following statements about IgA is/are correct?
(A) It is secreted into colostrum.
(B) It is transported across the cell by transcytosis.
(C) Its secretion is facilitated by poly-Ig receptor.
(D) It primarily exists as a dimer in serum.

Q.43 The standard free energy changes for conversion of phosphoenol pyruvate (𝑃𝐸𝑃) to pyruvate, and 𝐴𝑇𝑃 synthesis are shown below.
𝑃𝐸𝑃 + 𝐻20 ⇌ 𝑝𝑦𝑟𝑢𝑣𝑎𝑡𝑒 + 𝑃i ∆𝐺10 = −61.9 𝑘𝐽 ∙ 𝑚𝑜𝑙-1
𝐴𝐷𝑃 + 𝑃i ⇌ 𝐴𝑇𝑃 + 𝐻2o ∆𝐺10 = 30.5 kj. mol -1 .

The starting concentrations of 𝑃𝐸𝑃, 𝐴𝐷𝑃, 𝑝𝑦𝑟𝑢𝑣𝑎𝑡𝑒, and 𝐴𝑇𝑃 are 25, 25, 50, and 50 𝑚𝑀, respectively. The value of universal gas constant (R) is 8.315 𝐽 ∙ 𝑚𝑜𝑙-1 k-1. The actual free energy change in 𝑘𝐽 ∙ 𝑚𝑜𝑙-1 for the reaction
𝑃𝐸𝑃 + 𝐴𝐷𝑃 → 𝑝𝑦𝑟𝑢𝑣𝑎𝑡𝑒 + 𝐴𝑇𝑃

Carried out at 37 ℃ will be _ (rounded off to one place of decimal).

Q.44 The dissociation constant for a receptor-ligand pair is 0.25 × 107 . The ligand was added to a solution of the receptor such that the receptor was 50% saturated at equilibrium. Assume that the receptor has one ligand binding site. The concentration of the free ligand at equilibrium in 𝑛𝑀, correct to the nearest integer, should be _.

Q.45 The half-maximal velocity of an enzyme catalyzed reaction was found at a substrate concentration of 0.5 × 10-6. This enzyme follows Michaelis-Menten kinetics. In the presence of a competitive inhibitor, the half-maximal velocity was found at a substrate concentration of 1.5 × 10-6. Given that the enzymeinhibitor pair has a dissociation constant of 2 × 107, the concentration of the
competitive inhibitor in µ𝑀, rounded off to one place of decimal, was_____.

Q.46 A forty-times diluted sample of ssRNA gave an A260 of 0.01. The concentration of the ssRNA before the dilution in µ𝑔/𝑚𝐿 was _ (correct to the nearest integer).

## Botany XL (R): Q.47 – Q.54 Carry ONE mark Each

Q.47 In Angiosperms, normally ‘Exarch Xylem’ occurs in

(A) dicot stem
(B) monocot stem
(C) dicot root
(D) dicot leaf

Q.48 ‘Quiescent Center’ is present in

(A) leaf meristem
(B) root apical meristem
(C) shoot apical meristem
(D) floral meristem

Q.49 With reference to virulence (vir) region of nopaline type Ti plasmid ofAgrobacterium tumefaciens, match Group-I (vir gene) and Group-II (coded protein) in CORRECT combination.
Group-I Group-II

(A) P-IV, Q-III, R-II, S-I
(B) P-IV, Q-III, R-I, S-II
(C) P-IV, Q-II, R-I, S-III
(D) P-I, Q-III, R-II, S-IV

Q.50 Anomalous secondary growth is observed in
(A) Triticum
(B) Oryza
(C) Zea
(D) Dracaena

Q.51 Which of the following plant diseases is/are caused by bacteria?
(A) Angular leaf spot of cotton
(B) Citrus canker
(C) Apple scab
(D) Leaf curl of papaya

Q.52 Phylogenetic system of classification is/are proposed by
(A) Carolus Linnaeus
(B) John Hutchinson
(C) Engler and Prantl
(D) Bentham and Hooker

Q.53 Which of the following is/are part of marine ecosystem?
(A) Open ocean
(B) Chaparral
(C) Deep sea
(D) Estuaries

Q.54 In NADP+ -malic enzyme type C4 photosynthesis cycle, n molecule(s) of ATP is/are
required for the assimilation of one molecule of CO2. The value of n is __ (in integer).

## Q.55 – Q.65 Carry TWO marks Each

Q.55 An Arabidopsis thaliana mutant plant developed defective flowers with altered floral organ identity and patterning. In this mutant, the four floral whorls contain Sepal-Sepal-Carpel-Carpel, from the periphery to the center of the flower.

Based on the typical ABC model of floral organ patterning, which among the following are mutated in this plant?

(A) Class A gene(s)
(B) Class B gene(s)
(C) Class C gene(s)
(D) Double mutant for Class A and Class C genes

Q.56 Match the secondary metabolites in Group-I with types of secondary metabolites in Group-II in CORRECT order.

(A) P-I, Q-V, R-II, S-IV, T-III
(B) P-V, Q-II, R-IV, S-I, T-III
(C) P-II, Q-III, R-IV, S-V, T-I
(D) P-V, Q-I, R-II, S-IV, T-III