GATE 2021 Question Paper XL Q Life Sciences - Biochemistry

Q.1 – Q.10 Multiple Choice Question (MCQ), carry ONE mark each (for each wrong
answer: – 1/3).

Q.1 Which one of the following molecules (~ 1mg/mL) do NOT absorb at 280 nm
in an aqueous solution of pH 7.00 at room temperature?

(A) Poly deoxy-Guanylate (poly dG)

(B) Adenosine triphosphate

(C) Phenylalanine

(D) Tyrosine

Q.2 A molecule that forms a donor-acceptor energy transfer pair with the dansyl
group is ______

(A) Aspartate

(B) Histidine

(C) Lysine

(D) Tryptophan

Q.3 The stationary phase used in gel filtration chromatography is composed of
____

(A) Blue dextran

(B) Carboxymethyl (CM) cellulose

(C) Diethylaminoethyl (DEAE) cellulose

(D) Sepharose

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Q.4 According to the “wobble hypothesis” inosine at the third position of the
anticodon cannot form hydrogen bonds with ________

(A) Adenine

(B) Cytidine

(C) Guanine

(D) Uracil

Q.5 pKa value of the guanidinium group of Arginine is _____

(A) 4.30

(B) 7.40

(C) 9.20

(D) 12.50

Q.6 The non-coenzyme vitamin is ________

(A) Ascorbic acid

(B) Folic acid

(C) Nicotinic acid

(D) Thiamine

Q.7 Telomerase has a function similar to __________

(A) DNA dependent DNA polymerase

(B) RNA polymerase

(C) DNA gyrase

(D) Reverse transcriptase

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Q. 8 Which one of the following enzymes is used in Polymerase Chain Reaction ?

(A) Klenow fragment

(B) Taq polymerase

(C) T7 polymerase

(D) Primase

Q. 9 In hepatocytes, the detoxification of drugs occurs in ______

(A) Golgi apparatus

(B) Nucleolus

(C) Rough endoplasmic reticulum

(D) Smooth endoplasmic reticulum

Q.10 Which one of the following antibiotics can form an ion channel in the
bacterial membrane?

(A) Ampicillin

(B) Gramicidin A

(C) Gentamicin

(D) Rifampicin

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Q.11 – Q.12 Multiple Choice Question (MCQ), carry TWO mark each (for each wrong
answer: – 2/3).

Q.11 Which one of the following cells lack hypoxanthine-guanine
phosphoribosyltransferase (HGPRT)?

(A) B Cell

(B) T Cell

(C) Macrophage

(D) Myeloma Cell

Q.12 Which of the following lipids is non-ionic?

(A) Sphingomyelin

(B) Galactocerebroside

(C) Lecithin

(D) Phosphatidyl inositol

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Q.13 – Q.20 Multiple Select Question (MSQ), carry TWO mark each (no negative marks).

Q.13 Anti-B antibodies are present in the serum of ________

(A) Blood group A

(B) Blood group B

(C) Blood group AB

(D) Blood group O

Q.14 Which of the following are energy requiring processes?

(A) Facilitated diffusion

(B) Active transport

(C) Nonmediated transport

(D) Na+/K+ transport

Q.15 Which of the following are correctly paired?

(A) Replication: DnaA

(B) Recombination: RecA

(C) DNA repair: Rho factor

(D) Transcription: Sigma factor

Q.16 The high energy compound(s) is/are:

(A) Phosphoenol pyruvate

(B) Adenosine monophosphate

(C) 1,3-Bisphosphoglycerate

(D) Vitamin K

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Q.17 Given below are four plots obtained from separate experiments on enzyme
inhibition kinetics. The velocity (v) of the reaction is plotted at varying
concentrations of substrate (s) and inhibitor (I). The plot(s) corresponding to
competitive inhibition is/are

(A) (i)

(B) (ii)

(C) (iii)

(D) (iv)

Q.18 With respect to sodium dodecyl sulphate - polyacrylamide gel electrophoresis
(SDS-PAGE), which of these statement(s) is/are true?

(A) Ethidium bromide is used to track the progress of electrophoretic mobility

(B) -mercaptoethanol is used to reduce disulphide bonds

(C) The protein migrates towards the anode

(D) The lower molecular weight protein migrates slower than the larger molecular
weight protein

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Q.19 In the plot given below, the solid line represents oxygen binding to hemoglobin
under physiological conditions. The broken line represents the condition(s) of

(A) High CO2 concentration

(B) Increase in 2,3- Bisphosphoglycerate concentration

(C) High pH

(D) Loss of cooperativity

Q.20 Considering the open chain forms, which of the following pair(s) represent/s an
epimer?

(A) D-mannose and D-fructose

(B) D-glucose and D-mannose

(C) D-glucose and D-fructose

(D) D-galactose and D-glucose

END OF THE QUESTION PAPER

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