Explore topic-wise MCQs in Molecular Biology.

This section includes 64 Mcqs, each offering curated multiple-choice questions to sharpen your Molecular Biology knowledge and support exam preparation. Choose a topic below to get started.

51.

Nucleoside is a pyrimidine or purine base

A. covalently bonded to a sugar
B. ionically bonded to a sugar
C. hydrogen bonded to a sugar
D. none of the above
Answer» B. ionically bonded to a sugar
52.

Because DNA is a highly charged polyanion, its stability to heat denaturation

A. does not depend on hydrophobic interactions
B. increases with increasing salt
C. is independent of G - C content
D. decreases with increasing salt
Answer» C. is independent of G - C content
53.

Which pyrimidine base contains an amino group at carbon 4?

A. Cytosine
B. Thymine
C. Uracil
D. Adenine
Answer» B. Thymine
54.

In gel electrophoresis, what fragments will move most quickly through a gel?

A. Large fragments
B. Small fragments
C. Large genome
D. None of these
Answer» C. Large genome
55.

WHICH_OF_THE_FOLLOWING_FACTORS_DO_NOT_PROVIDE_TO_THE_SEPARATION_OF_DNA_FRAGMENTS_DURING_ELECTROPHORESIS??$

A. Chargaff’s rule
B. Matrix density
C. Ethidium bromide
D. Size
Answer» D. Size
56.

Which one of the following is not a function of a nucleotide?$

A. Nucleic acid monomer
B. Ribozyme
C. Energy carrier molecules
D. Receptors
Answer» E.
57.

Which of the following is not a characteristic of nucleotide bases?

A. Planar
B. Heterocyclic
C. Aliphatic
D. Ubiquitous
Answer» D. Ubiquitous
58.

In a diploid organism with 30,000 bases haploid genome contains 23% A residues. What is the number of G residues in the genome of this organism?

A. 16000
B. 16200
C. 16500
D. 14200
Answer» C. 16500
59.

In one strand of a double stranded DNA the rate of occurrence of A is 3 times C in consecutive 10 bases. So how many G will be there in 100 base pairs of a DNA duplex?[Consider G=T in one strand].

A. 30
B. 20
C. 40
D. 60
Answer» D. 60
60.

According to Chargaff’s rule the two strands of DNA has ___________$

A. Same molecular weight
B. Same amount of A and G
C. Different amount of A and G
D. Different molecular weight
Answer» E.
61.

Which of the following is not a component of the nucleic acid backbone?

A. Pentose sugar
B. Phosphate group
C. Nucleotide
D. Phosphodiesterase bond
Answer» D. Phosphodiesterase bond
62.

With respect to nucleosides which of the following is paired correctly?

A. Purine – Adenosine, Thymidine
B. Purine – Guanosine, Thymidine
C. Pyrimidine – Uridine, Cytidine
D. Pyrimidine – Uridine, Adenosine
Answer» D. Pyrimidine ‚Äö√Ñ√∂‚àö√ë‚àö¬® Uridine, Adenosine
63.

Which of the following is wrongly paired?

A. Proteins – peptide bond
B. Nucleic acid – hydrogen bond
C. Polysaccharide – glycosidic bond
D. Phospholipids –phosphate linkage
Answer» C. Polysaccharide ‚Äö√Ñ√∂‚àö√ë‚àö¬® glycosidic bond
64.

Which macromolecule is not abundantly found though being of critical importance for biological mechanism?

A. Proteins
B. Lipids
C. Nucleic acids
D. Polysaccharides
Answer» C. Nucleic acids