Explore topic-wise MCQs in Biochemistry.

This section includes 199 Mcqs, each offering curated multiple-choice questions to sharpen your Biochemistry knowledge and support exam preparation. Choose a topic below to get started.

1.

Gain of electrons can be termed as

A. Metabolism
B. Anabolism
C. Oxidation
D. Reduction
Answer» E.
2.

The major factor(s) determining whether glucose is oxidized by aerobic or anaerobic glycolysis is/are

A. Ca⁺²
B. FADH₂
C. NADH and the ATP/ADP ratio
D. Presence of high AMP
Answer» D. Presence of high AMP
3.

Cleavage of Fructose 1, 6-biophosphate yields

A. Two aldoses
B. Two ketoses
C. An aldose and a ketose
D. Only a ketose
Answer» D. Only a ketose
4.

Formation of one molecule of glucose from pyruvate requires

A. 4 ATP, 2 GTP and 2 NADH
B. 3 ATP, 2 GTP and 2 NADH
C. 4 ATP, 1 GTP and 2 NADH
D. 2 ATP, 2 GTP and 2 NADH
Answer» B. 3 ATP, 2 GTP and 2 NADH
5.

Maltose hydrolysis yields

A. D-galactose and D-glucose
B. 2-Dglucose
C. n-Dglucose
D. 2-Dfructose
Answer» C. n-Dglucose
6.

Which of the following is false about acetyl-coA?

A. It is a thioester
B. It has a large, negative standard free energy of hydrolysis
C. It contains phosphorous atom in the position occupied by an oxygen atom in oxygen esters
D. It contains sulfur atom in the position occupied by an oxygen tom in oxygen esters
Answer» D. It contains sulfur atom in the position occupied by an oxygen tom in oxygen esters
7.

Glucagon is released from

A. Muscle
B. Pancreas
C. Kidneys
D. Epithelial tissues
Answer» C. Kidneys
8.

If ∆G‘° of the reaction A → B is -40kJ/mol under standard conditions then the reaction

A. Will never reach equilibrium
B. Will not occur spontaneously
C. Will proceed at a rapid rate
D. Will proceed from left to right spontaneously
Answer» E.
9.

The end products in ethanol fermentation are

A. Ethanol and CO₂
B. Ethanol and O₂
C. Ethanol, H₂ and CO₂
D. Ethanol, O₂ and CO₂
Answer» B. Ethanol and O₂
10.

Which of the following enzyme is present in saliva?

A. Hexokinase
B. Alpha amylase
C. Fructokinase
D. Triose kinase
Answer» C. Fructokinase
11.

The compounds responsible for coordinated regulation of glucose and glycogen metabolism are

A. NADH
B. NAD⁺
C. Acetyl co-A
D. Fructose 2, 6-bisphosphate
Answer» E.
12.

Which of the following enzymes is involved in fatty acid synthesis?

A. Hexokinase II
B. Hexokinase IV
C. PFK-2/FBPase-2
D. Pyruvate dehydrogenase
Answer» E.
13.

Which of the following is not an important precursor of glucose in animals?

A. Lactate
B. Pyruvate
C. Glycerol
D. Glucose 6-phosphate
Answer» E.
14.

Oxaloacetate is reduced to malate by

A. Pyruvate carboxylase
B. Malate dehydrogenase
C. Pyruvate kinase
D. Phosphofructokinase-1
Answer» C. Pyruvate kinase
15.

Manganese is needed for

A. normal bone structure
B. reproduction and functioning of central nervous system
C. both (a) and (b)
D. muscle strengthening
Answer» D. muscle strengthening
16.

Water does a nucleophilic attack on phosphate monoester producing

A. Phosphorous chloride
B. Phosphorous sulfide
C. Inorganic phosphate
D. Organic phosphate
Answer» D. Organic phosphate
17.

Glycogen synthase a is activated by

A. Phosphorylation catalyzed by GSK3
B. Dephosphorylation catalyzed by GSK3
C. Phosphorylation catalyzed by pyruvate kinase
D. Phosphorylation catalyzed by pyruvate carboxylase
Answer» B. Dephosphorylation catalyzed by GSK3
18.

Which of the following statements is false about ATP hydrolysis?

A. It is highly exergonic
B. Activation energy is relatively high
C. ∆G‘°=-30.5kJ/mol
D. ∆G‘°=30.5kJ/mol
Answer» E.
19.

Phosphoryl groups are derivatives of

A. Phosphorous acid
B. Phosphoric acid
C. Acetic acid
D. Citric acid
Answer» C. Acetic acid
20.

Wilson's disease is an example of __________ and Menkes' syndrome is an example of __________ .

A. zinc deficiency; zinc toxicity
B. zinc toxicity; zinc deficiency
C. copper deficiency; copper toxicity
D. copper toxicity; copper deficiency
Answer» E.
21.

What is the relation between elasticity coefficient, flux coefficient and response coefficient?

A. R = C.ε
B. R = C⁄ε
C. R = ε⁄C
D. ε = C.R
Answer» B. R = C⁄ε
22.

Which of the following statements is correct about oxidative pentose phosphate pathway?

A. It generates NADH
B. It oxidizes NADPH to NADP⁺
C. The pathway supplies ribose 5-phosphate and NADPH in the quantities the cell requires
D. Glucose 6-phosphatase catalyzes the rate limiting reaction of the pathway
Answer» D. Glucose 6-phosphatase catalyzes the rate limiting reaction of the pathway
23.

The second control point in gluconeogenesis is the reaction catalyzed by

A. Pyruvate kinase
B. Pyruvate dehydrogenase
C. FBPase-1
D. PFK-1
Answer» D. PFK-1
24.

The phosphate groups used during glycolysis are

A. Organic
B. Inorganic
C. Neutral
D. None of the mentioned
Answer» C. Neutral
25.

Which is an example for electromagnetic to electrical energy conversion that occurs in living organisms

A. ATP-driven muscle contraction
B. ATP-dependent photon emission in fireflies
C. light-induced electron flow in chloroplasts
D. ATP-driven active transport across a membrane
Answer» D. ATP-driven active transport across a membrane
26.

The relationship between K‘eq and ∆G‘° is

A. ∆G‘° = RTlnK‘eq
B. ∆G‘° = -RTK‘eq
C. ∆G‘° = RK‘eq
D. ∆G‘° = -RK‘eq
Answer» C. ∆G‘° = RK‘eq
27.

Flux control coefficient measures the

A. Steady state change
B. pH change
C. Temperature change
D. Hormonal change
Answer» B. pH change
28.

The first step in the payoff phase of glycolysis is

A. Reduction of 1, 3-bisphosphoglycerate to glyceraldehyde 3-phosphate
B. Oxidation of glyceraldehyde 3-phosphate to 1, 3-bisphosphoglycerate
C. Reversible conversion of dihydroxyacetone phosphate to glyceraldehyde 3-phosphate
D. Irreversible conversion of dihydroxyacetone phosphate to glyceraldehyde 3-phosphate
Answer» C. Reversible conversion of dihydroxyacetone phosphate to glyceraldehyde 3-phosphate
29.

Which group is most often affected with copper deficiency?

A. Elderly woman
B. Alcoholics
C. Active toddlers with limited
D. Preterm infants food variety
Answer» B. Alcoholics
30.

Which of the following carbohydrate is effective in promoting the calcium absorption?

A. Lactose
B. Maltose
C. Sucrose
D. Xylose
Answer» B. Maltose
31.

Which is an example for chemical to mechanical energy conversion that occurs in living organisms?

A. ATP-driven muscle contraction
B. ATP-dependent photon emission in fireflies
C. light-induced electron flow in chloroplasts
D. ATP-driven active transport across a membrane
Answer» B. ATP-dependent photon emission in fireflies
32.

Which of the following statements is false about gluconeogenesis?

A. From the hydrolysis of tri-acyl-glycerol, fatty acids can be used as a carbon source
B. From red blood cells, lactate can be used as a carbon source
C. From the hydrolysis of tri-acyl-glycerol, glycerol is converted to glucose in gluconeogenesis
D. From muscle vigorous muscle activity, lactate can be used as a carbon source
Answer» B. From red blood cells, lactate can be used as a carbon source
33.

An expression for the experimentally determined change in flux through a pathway in response to a regulatory hormone or second messenger

A. Response coefficient
B. Elasticity coefficient
C. Flux control coefficient
D. Metabolic control
Answer» B. Elasticity coefficient
34.

Which of the following is a potent regulator of glycolysis and gluconeogenesis?

A. Fructose 2, 6-bisphosphate
B. Fructose 1, 6-bisphosphate
C. Fructose 6-phosphate
D. Glucose 1, 6-bisphosphate
Answer» B. Fructose 1, 6-bisphosphate
35.

Three reactions of glycolysis are so exergonic, which are not catalyzed by

A. Hexokinase
B. PFK-1
C. Pyruvate kinase
D. Pyruvate dehydrogenase
Answer» E.
36.

Loss of electrons can be termed as

A. Metabolism
B. Anabolism
C. Oxidation
D. Reduction
Answer» D. Reduction
37.

Which of the following is involved in triacylglycerol synthesis?

A. Hexokinase II
B. Acyl co-A glycerol transferases
C. PFK-2/FBPase-2
D. Pyruvate dehydrogenase
Answer» C. PFK-2/FBPase-2
38.

For a reaction if ∆G° is positive, then

A. The products will be favored
B. The reactants will be favored
C. The concentration of the reactants and products will be equal
D. All of the reactant will be converted to products
Answer» C. The concentration of the reactants and products will be equal
39.

An endergonic reaction

A. Proceeds spontaneously
B. Does not require activation energy
C. Releases energy
D. Requires energy
Answer» E.
40.

Which out of the following statements is true about regulation of metabolic pathway?

A. Most of the metabolic pathways are regulated
B. Most of the metabolic pathways are not regulated
C. Regulation of metabolic pathways always involves changing the amount of enzymes
D. Metabolic regulation always depends on control by hormones
Answer» B. Most of the metabolic pathways are not regulated
41.

Which out of the following enzymes can utilize both NAD⁺ and NADP⁺ as a coenzyme?

A. Glutamate dehydrogenase
B. Alcohol dehydrogenase
C. Aldehyde dehydrogenase
D. Glycerol-3-P ddehydrogenase
Answer» B. Alcohol dehydrogenase
42.

Which of the following enzyme catalyzes the first step in the catabolism of ethanol?

A. Alcohol dehydrogenase
B. Lactate dehydrogenase
C. Glutamate dehydrogenase
D. Malate dehydrogenase
Answer» B. Lactate dehydrogenase
43.

Which out of the following has the highest redox potential?

A. NAD
B. FMN
C. FAD
D. O₂
Answer» E.
44.

Enzyme involved in the pathway of synthesis of acetyl-coA

A. Hexokinase
B. Pyruvate decarboxylase
C. Pyruvate dehydrogenase
D. Pyruvate kinase
Answer» D. Pyruvate kinase
45.

High concentration of glucose 6-phosphate is inhibitory to

A. Hexokinase
B. Pyruvate kinase
C. Glucokinase
D. Phosphofructokinase-1
Answer» B. Pyruvate kinase
46.

Which of the following statements is true regarding acetyl co-A?

A. It stimulates pyruvate dehydrogenase
B. It stimulates pyruvate carboxylase
C. It inhibits pyruvate carboxylase
D. It stimulates hexokinase
Answer» C. It inhibits pyruvate carboxylase
47.

Gluconeogenesis responds to which of the following?

A. Hormonal control
B. pH control
C. Temperature control
D. Blood control
Answer» B. pH control
48.

Which one out of the following is not a NAD⁺ requiring enzyme?

A. Lactate dehydrogenase
B. Pyruvate dehydrogenase complex
C. Maltate dehydrogenase
D. Acyl co-A dehydrogenase
Answer» E.
49.

Which of the following statements about redox potential is false?

A. NADH/NAD⁺ redox pair has the least redox potential
B. Oxygen/H₂O redox pair has the highest redox potential
C. The components of electron transport chain are organized in terms of their redox potential
D. The redox potential of a system is usually compared with the potential of the hydrogen electrode
Answer» B. Oxygen/H₂O redox pair has the highest redox potential
50.

Some regulated enzymes rebalance the level of metabolites in response to the change in flux, this activity is

A. Regulation
B. Control
C. Metabolism
D. Anabolism
Answer» B. Control