GATE 2021 Question Paper XL T Life Sciences - Zoology

Q.1 – Q.7 Multiple Choice Question (MCQ), carry ONE mark each (for each wrong
answer: – 1/3).

Q.1 Ichthyophis belongs to which of the following Class?

(A) Mammalia

(B) Reptilia

(C) Amphibia

(D) Aves

Q.2 The two homologous genes occurring in different species are called

(A) paralogous

(B) orthologous

(C) pseudologous

(D) prologous

Q. 3 The expression of holandric genes causes which of the following genetic trait
in humans?

(A) Haemophilia

(B) Sickle cell anaemia

(C) Down’s Syndrome

(D) Hypertrichosis

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Q.4 Assume that the anticodon for an unknown amino acid is 3ʹ AUG 5ʹ. The
corresponding code on DNA sequence would be

(A) 3ʹ TAC 5ʹ

(B) 5ʹ TAG 3ʹ

(C) 3ʹ ATG 5ʹ

(D) 5ʹ ATG 3ʹ

Q. 5 The Organ of Corti is found in which of the following parts of human
body?

(A) Heart

(B) Inner ear

(C) Kidney

(D) Nasal cavity

Q. 6 In adult athletes, muscles grow larger when exercised and are capable of
regeneration after injury. This is due to proliferation and differentiation of

(A) satellite cells

(B) myelin sheath

(C) oxyntic cells

(D) choanocytes

Q. 7 The term innate behavior is a sort of animal behavior that is

(A) triggered by an environmental change

(B) learnt by hit-and-trial approach

(C) trained and taught by the parent

(D) fixed developmentally at the genetic level

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Q.8 – Q.10 Numerical Answer Type (NAT), carry ONE mark each (no negative marks).

Q.8 A man, whose mother and father had blood groups A and O respectively,
marries a woman with blood group AB. If the man has blood group A, then
the number of different blood groups possible among their children will be
_________ (in integer).

A population of snakes in an isolated island is in Hardy–Weinberg
equilibrium for a gene with only two alleles (A and a). If the allelic frequency
Q. 9
of A is 0.6, then the genetic frequency of Aa is _________ (round off to 2
decimal places).

Q.10 In the structure of a polypeptide, one -helix (3.613 helix) contains 32 intra-
chain hydrogen bonds. The number of turns in the helix will be _________
(in integer).

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Q.11 – Q. 16 Multiple Choice Question (MCQ), carry TWO marks each (for each wrong
answer: – 2/3).

Q.11 Match the terms in Column I with the specific descriptions in Column II
Column I Column II
P. Zygote (i) A hollow sphere of cells
Q. Morula (ii) A newly born offspring
R. Blastocyst (iii) A cell that results from fertilization
S. Ovum (iv) An embryo
T. Neonate (v) An unfertilized egg
U. Fetus (vi) A compact mass of cells

(A) P-(iii), Q-(vi), R-(i), S-(v), T-(ii), U-(iv)

(B) P-(v), Q-(ii), R-(iii), S-(vi), T-(i), U-(iv)

(C) P-(ii), Q-(iv), R-(vi), S-(v), T-(i), U-(iii)

(D) P-(iii), Q-(vi), R-(ii), S-(v), T-(iv), U-(i)

Q. 12 Match the autoimmune diseases in Column I for the self-antigens in
Column II
Column I Column II
P. Rheumatoid arthritis (i) Myelin
Q. Systemic lupus erythematosus (ii) Connective tissue
R. Myasthenia gravis (iii) DNA
S. Multiple sclerosis (iv) Acetylcholine receptors

(A) P-(i), Q-(ii), R-(iii), S-(iv)

(B) P-(ii), Q-(iii), R-(iv), S-(i)

(C) P-(iii), Q-(i), R-(iv), S-(ii)

(D) P-(iv), Q-(i), R-(ii), S-(iii)

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Q. 13 Match the types of cell movements during gastrulation in Column I with the
descriptions in Column II

Column I Column II

P. Invagination (i) Migration of individual cells from the surface into
the embryo’s interior

Q. Involution (ii) Infolding of a sheet (epithelium) of cells during
the formation of endoderm in sea urchin

R. Ingression (iii) Splitting of one cellular sheet into two nearly
parallel sheets

S. Delamination (iv) Inward movement of an expanding outer layer of
cells so that it spreads over the internal surface of
the remaining external cells

(A) P-(ii), Q-(iii), R-(iv), S-(i)

(B) P-(iv), Q-(i), R-(iii), S-(ii)

(C) P-(ii), Q-(iv), R-(i), S-(iii)

(D) P-(iii), Q-(ii), R-(iv), S-(i)

Q. 14 Match the therapeutic factors in Column I with the applications in Column
II
Column I Column II
P. Humulin (i) Cancer therapy
Q. Erythropoietin (ii) Diabetes
R. Plasminogen activator (iii) Osteoporosis
S. Cathepsin K inhibitor (iv) Anaemia
T. Leptin (v) Myocardial infraction
(vi) Obesity

(A) P-(ii), Q-(iv), R-(v), S-(iii), T-(vi)

(B) P-(ii), Q-(v), R-(i), S-(iv), T-(iii)

(C) P-(v), Q-(vi), R-(iv), S-(iii), T-(i)

(D) P-(iii), Q-(iv), R-(ii), S-(v), T-(vi)

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Q. 15 Match the cell organelles in Column I with the appropriate functions in
Column II

Column I Column II
P. Peroxisome (i) Conversion of lipid to carbohydrate
Q. Endoplasmic reticulum (ii) Oxidation of fatty acids
R. Glyoxysome (iii) N-linked glycosylation
S. Golgi complex (iv) Microtubule organization center
T. Centrioles (v) O-linked glycosylation

(A) P-(ii), Q-(iii), R-(v), S-(i), T-(iv)

(B) P-(iv), Q-(v), R-(i), S-(ii), T-(iii)

(C) P-(iv), Q-(v), R-(iii), S-(i), T-(ii)

(D) P-(ii), Q-(iii), R-(i), S-(v), T-(iv)

Q. 16 Cohesin and Condensin proteins of eukaryotes belong to which one of the
following groups?

(A) Structural maintenance of chromosomes (SMC) proteins

(B) Histones

(C) DNA polymerases

(D) Topoisomerases

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Q.17 – Q.18 Multiple Select Question (MSQ), carry TWO mark each (no negative
marks).

Q. 17 Which of the following options represent the animals as Endemic to India?

(A) Pygmy Hog

(B) Mountain Bongo

(C) Hirola

(D) Purple Frog

Q. 18 Which of the following amino acids contain more than one chiral center?

(A) Leucine

(B) Isoleucine

(C) Serine

(D) Threonine

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Q.19 – Q.20 Numerical Answer Type (NAT), carry TWO mark each (no negative
marks).

Q. 19 An enzyme catalyzes the conversion of 30 µM of a substrate to product at
reaction velocity of 9.0 µM s-1. When [Et] = 30 nM and Km = 10 µM, Kcat / Km
of enzyme will be n × 107 M-1 s-1. The value of n is _________ (in integer).

Q. 20 A cross is made between two animals of genotypes AaBb x AaBb, where loci
A and loci B assort independently. The progeny of this dihybrid cross was
then allowed to self-cross. The proportion of the progeny that showed
segregation for loci A (i.e., produce A- and aa progeny) in % will be
_________ (in integer).

END OF THE QUESTION PAPER

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