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.

151.

Restriction maps

A. allows comparison between DNA molecules without the need to determine nucleotide sequence
B. allows comparison between DNA molecules but requires to determine nucleotide sequence
C. does not allow comparison between DNA molecules
D. none of the above
Answer» B. allows comparison between DNA molecules but requires to determine nucleotide sequence
152.

ATP is from which general category of molecules?

A. Polysaccharides
B. Proteins
C. Nucleotides
D. Amino acids
Answer» D. Amino acids
153.

In glycolysis, ATP is formed by the transfer of a high-energy phosphate from 1,3-bisphosphoglycerate to ADR No such high-energy phosphate donor has ever been isolated in mitochondria because

A. the techniques for isolating the phosphate donor are not refined enough
B. no such phosphate donor exists
C. the high-energy phosphate donor is very short-lived and difficult to isolate
D. None of the above
Answer» C. the high-energy phosphate donor is very short-lived and difficult to isolate
154.

Which of the following is not true of glycolysis?

A. ADP is phosphorylated to ATP via substrate level phosphorylation
B. The pathway does not require oxygen
C. The pathway oxidizes two moles of NADH to NAD+ for each mole of glucose that enters
D. The pathway requires two moles of ATP to get started catabo-lizing each mole of glucose
Answer» D. The pathway requires two moles of ATP to get started catabo-lizing each mole of glucose
155.

When concentration of the reactants is higher than the equilibrium concentration then

A. the gibbs free energy will be positive
B. the gibbs free energy will be negative
C. more products will be formed
D. both (b) and (c)
Answer» E.
156.

The glycolytic pathway (glucose → 2 pyruvate) is found

A. in all living organisms
B. primarily in animals excluding particles
C. only in eukaryotes
D. only in yeast
Answer» B. primarily in animals excluding particles
157.

DNA fragments in a restriction digest can be separated by electrophoresis in

A. poly acrylamide
B. agarose gel
C. both (a) and (b)
D. none of these
Answer» D. none of these
158.

What technique can be used to determine the murderer who left blood with the victim?

A. DNA sequencing
B. PCR amplification
C. Western blot
D. RFLP mapping
Answer» C. Western blot
159.

Double stranded DNA denaturation with specified limit of temperature is

A. reversible reaction
B. irreversible reaction
C. either (a) or (b)
D. none of these
Answer» B. irreversible reaction
160.

The viruses that can achieve neoplastic transformation are called

A. DNA tumor viruses
B. RNA tumor viruses
C. retroviruses HIV
D. none of these
Answer» B. RNA tumor viruses
161.

For gene transfer to be effective, transforming DNA must be

A. incorporated into the bacterial chromosome
B. incorporated into a viral genome
C. free in the bacterial cytoplasm
D. none of the above
Answer» B. incorporated into a viral genome
162.

Which of the following regulates glycolysis steps?

A. Phosphofructokinase
B. Hexose kinase
C. Pyruvate kinase
D. All of these
Answer» E.
163.

Fructose-2,6-bisphosphate

A. activates fructose-1,6-bisphosphatase
B. activates phosphofructokinase
C. inhibits fructose-1,6-bisphosphatase
D. both (b) and (c)
Answer» E.
164.

Glycogen has

A. α-1,4 linkage
B. α-1,6 linkages
C. α-1,4 and α-1,6 linkages
D. α-1,4 and β-1,6 linkage
Answer» D. α-1,4 and β-1,6 linkage
165.

Glucose from the breakdown of glycogen is obtained in

A. the liver by phosphorolysis
B. the muscles by phosphorolysis
C. the muscles by hydrolysis
D. both (a) and (b)
Answer» E.
166.

What condition is caused by iodine deficiency during pregnancy and is characterized by stunted growth, deafness, and mental retardation?

A. Cretinism
B. Keshan disease
C. Multiple sclerosis
D. Crohn's disease
Answer» B. Keshan disease
167.

Chronic consumption of excess selenium can lead to

A. brittle hair and nails.
B. muscle weakness,
C. TPN
D. diarrhea.
Answer» C. TPN
168.

During glycolysis, the major energy generating step involves

A. pyruvate kinase
B. phosphoglycerate kinase
C. glyceraldehyde-3 -dehydrogenase
D. Phosphofructokinase
Answer» D. Phosphofructokinase
169.

The general term used for the anaerobic degradation of glucose to obtain energy is

A. Anabolism
B. Oxidation
C. Fermentation
D. Metabolism
Answer» D. Metabolism
170.

Unfolding of regular secondary protein structure causes

A. Large decrease in the entropy of the protein
B. Little increase in the entropy of protein
C. No change in the entropy of the protein
D. Large increase in the entropy of the protein
Answer» E.
171.

The study of energy relationships and conversions in biological systems is called as

A. Biophysics
B. Biotechnology
C. Bioenergetics
D. Microbiology
Answer» D. Microbiology
172.

The PCR, polymerase chain reaction is becoming the method of choice for

A. Alteration of gene
B. screening gene
C. sterilization of gene
D. all of these
Answer» C. sterilization of gene
173.

Site directed mutagenesis facilitated research on

A. Carbohydrates
B. Proteins
C. Lipids
D. Fats
Answer» C. Lipids
174.

Dextrin hydrolysis yields

A. D-galactose and D-glucose
B. 2-Dglucose
C. n-Dglucose
D. 2-Dfructose
Answer» D. 2-Dfructose
175.

Glycolysis converts

A. Glucose into pyruvate
B. Glucose into phosphoenolpyruvate
C. Fructose into pyruvate
D. Fructose into phosphoenolpyruvate
Answer» B. Glucose into phosphoenolpyruvate
176.

The product formed in the first substrate level phosphorylation in glycolysis is

A. Pyruvate
B. 3-phosphoglycerate
C. 1, 3-bisphosphoglycerate
D. 2-phosphoglycerate
Answer» C. 1, 3-bisphosphoglycerate
177.

An endemic disease of cardiomyopathy in children is attributed to

A. low Se in the environment
B. low intake of iron
C. high Se in the environment
D. high intake of iron
Answer» B. low intake of iron
178.

Manganese is a key component of all of the following enzymes except

A. arginase
B. pyruvate carboxylase
C. ceruloplasmin
D. Mn-superoxide dismutase
Answer» D. Mn-superoxide dismutase
179.

In a PCR reaction after four cycles, each molecule of a duplex DNA will give rise to

A. 16 single strands of DNA
B. 16 double stranded DNA
C. 18 single strands of DNA
D. 18 double stranded DNA
Answer» B. 16 double stranded DNA
180.

Consumption of which nutrient leads to the multiplication of oral bacteria?

A. Fat
B. Carbohydrate
C. Protein
D. Fluoride
Answer» C. Protein
181.

The mineral which is considered important in maintaining electrical potential in nerves and membranes is

A. magnesium
B. manganese
C. calcium
D. iron
Answer» B. manganese
182.

TPP (thiamine pyrophosphate) is derived from

A. Vitamin A
B. Vitamin B1
C. Vitamin C
D. Vitamin B2
Answer» C. Vitamin C
183.

In the reduction of pyruvate to lactate, which of the following is regenerated?

A. H⁺
B. NADH
C. NAD⁺
D. Na⁺
Answer» D. Na⁺
184.

For its activity, pyruvate decarboxylase requires

A. Mg⁺²
B. Ca⁺²
C. Na⁺
D. H⁺
Answer» B. Ca⁺²
185.

For every one molecule of sugar glucose which is oxidized __________ molecule of pyruvic acid are produced.

A. 1
B. 2
C. 3
D. 4
Answer» C. 3
186.

The enzymes of glycolysis in a eukaryotic cell are located in the

A. intermembrane space
B. plasma membrane
C. cytosol
D. mitochondrial matrix
Answer» D. mitochondrial matrix
187.

The amount of energy received from one ATP is

A. 76 kcal
B. 7.3 kcal
C. 760 kcal
D. 1000 kcal
Answer» C. 760 kcal
188.

The active form of glycogen phosphorylase is phosphorylated, while the dephosphorylation of which active form occurs?

A. Glycogen synthase
B. Glycogen semisynthase
C. Glycogen hydrolase
D. Glycogen dehydrogenase
Answer» B. Glycogen semisynthase
189.

In the glycogen synthase reaction, the precursor to glycogen is

A. glucose-6-P
B. UTP-glucose
C. UDP-glucose
D. glucose-1-P
Answer» D. glucose-1-P
190.

Phosphofructokinase, the major flux-controlling enzyme of glycolysis is allosterically inhibited and activated respectively by

A. ATP and PEP
B. AMP and Pi
C. ATP and ADP
D. Citrate and ATP
Answer» D. Citrate and ATP
191.

From a single molecule of DNA, PCR can make

A. one additional copy
B. hundreds of copies
C. thousands of copies
D. millions of copies
Answer» E.
192.

Which of the following is not a mechanism for altering the flux of metabolites through the rate-determining step of a pathway?

A. Allosteric control of the enzyme activity
B. Diffusional coupling between adjacent active sites
C. Genetic control of the enzyme concentration
D. Covalent modification of the enzyme
Answer» C. Genetic control of the enzyme concentration
193.

Genomic libraries are made from

A. genomic DNA of an organism
B. genomic RNA of an organism
C. genomic cDNA of an organism
D. genomic mRNA of an organism
Answer» B. genomic RNA of an organism
194.

Which of the following could act as an uncoupler of electron transport and ATP synthesis?

A. The Fo base-piece of ATP synthase (without the Fl subunit)
B. Dinitrophenol
C. neither (a) nor (b)
D. Both (a) and (b)
Answer» E.
195.

To clone into a plasmid vector, both the plasmid and the foreign DNA are cut

A. with the same restriction enzyme and mixed together
B. with different restriction enzyme and mixed together
C. with the combination of enzymes and then seperated
D. with the combination of enzymes and mixed together
Answer» B. with different restriction enzyme and mixed together
196.

PCR is used

A. to diagnose genetic diseases
B. to solve crimes
C. to study gene function
D. all of these
Answer» E.
197.

Bacteriophages are

A. cells in the blood that eat bacteria
B. a class of bacteria
C. bacterial viruses
D. none of the above
Answer» D. none of the above
198.

Specialized transduction occurs when

A. the bacteriophage incorporates randomly in the bacterial chromosome
B. the bacteriophage never incorporates into the bacterial chromosome
C. the bacteriophage always incorporates at the same position in the bacterial chromosome
D. none of the above
Answer» D. none of the above
199.

PCR can be used to amplify a specific fragment of DNA from which of the following?

A. A drop of blood
B. A hair follicle
C. A fragment of skin
D. All of these
Answer» E.