Biochemistry in Biotechnology MCQs

Question 1

Which one of the following is INCORRECT about protein structures?

Accepted Answer

All parts of a fold can be classified as helices, strands or turns

Answer

A protein fold is stabilized by favorable noncovalent interactions

Answer

Two non-covalent atoms cannot be closer than the sum of their van der Waals radii

Answer

The peptide bond is nearly planar

Question 2

Which one of the following amino acids has three ionizable groups?

Accepted Answer

Lysine

Answer

Glycine

Answer

Leucine

Answer

Valine

Question 3

During lactic acid fermentation, net yield of ATP and NADH per mole of glucose is

Accepted Answer

2 ATP and 0 NADH

Answer

2 ATP and 2 NADH

Answer

4 ATP and 2 NADH

Answer

4 ATP and 0 NADH

Question 4

The reactions leading to the formation of amino acids from the TCA cycle intermediates are

Accepted Answer

Transamination

Answer

Carboxylation

Answer

Isomerization

Answer

Decarboxylation

Question 5

The catalytic efficiency for an enzyme is defined as

Accepted Answer

$$\frac{{{k_{cat}}}}{{{K_M}}}$$

Answer

$${K_{cat}}$$

Answer

$$\frac{{{V_{\max }}}}{{{k_{cat}}}}$$

Answer

$$\frac{{{K_{cat}}}}{{{v_{\max }}}}$$

Question 6

Which of the following types of molecules act as biological catalysts? P. Protein Q. RNA R. Phospholipid

Accepted Answer

P and Q only

Answer

P and R only

Answer

Q and R only

Answer

P, Q and R

Question 7

Which one of the following amino acids has the highest probability to be found on the surface of a typical globular protein in aqueous environment?

Accepted Answer

Arg

Answer

Ala

Answer

Val

Answer

Ile

Question 8

Determine the correctness or otherwise of the following Assertion (A) and the Reason (R). Assertion: A very low amount of inhibitor can act as an activator for allosteric enzymes. Reason: Allosteric enzymes follow Michaelis-Menten kinetics.

Accepted Answer

(A) is true but (R) is false

Answer

Both (A) and (R) are true and (R) is the correct reason for (A)

Answer

Both (A) and (R) are true but (R) is not the correct reason for (A)

Answer

(A) is false but (R) is true

Question 9

During photorespiration under low CO2 and high O2 levels, O2 reacts with ribulose 1, 5-bisphosphate to yield

Accepted Answer

One molecule each of 3-phosphoglycerate and 2-phosphoglycolate

Answer

Two molecules of 3-phosphoglycerate

Answer

Two molecules of 2-phosphoglycolate

Answer

One molecule each of 3-phosphoglycerate and glyoxylate