Explore topic-wise MCQs in Cell Biology.

This section includes 12 Mcqs, each offering curated multiple-choice questions to sharpen your Cell Biology knowledge and support exam preparation. Choose a topic below to get started.

1.

Which of the following enzyme is responsible for initiating DNA replication?

A. polymerase
B. ligase
C. primase
D. gyrase
Answer» D. gyrase
2.

Which enzyme joins the Okazaki fragments into a continuous strand?

A. gyrase
B. topoisomerase
C. ligase
D. helicase
Answer» D. helicase
3.

Who made the discovery that one DNA strand is synthesized discontinuously in fragments?

A. Francis Crick
B. Reiji Okazaki
C. James Watson
D. Louis Pasteur
Answer» C. James Watson
4.

The lagging strand is synthesized discontinuously.

A. True
B. False
Answer» B. False
5.

How many copies (approximately) of DNA polymerase III are present in a typical bacterial cell?

A. 10
B. 50
C. 100
D. 200
Answer» B. 50
6.

When was DNA polymerase III discovered as the major enzyme behind DNA replication in bacteria?

A. 1949
B. 1959
C. 1969
D. 1989
Answer» D. 1989
7.

Which enzyme removes the positive supercoils generated when the replication fork?

A. helicase
B. endonuclease
C. exonuclease
D. gyrase
Answer» E.
8.

Movement of the replication fork generates ________________ in the unreplicated portion of DNA.

A. positive supercoils
B. negative supercoils
C. untranslated regions
D. amino acid substitutions
Answer» B. negative supercoils
9.

The bacterial oriC is the __________________

A. specific sequence
B. transcription factor
C. enzyme
D. polypeptide
Answer» B. transcription factor
10.

Temperature-sensitive mutants can not replicate their chromosomes at non-permissive temperatures.

A. True
B. False
Answer» B. False
11.

Which isotopes were used by the researchers who first confirmed the semiconservative nature of DNA replication?

A. Nitrogen
B. Carbon
C. Oxygen
D. Sulfur
Answer» B. Carbon
12.

How many types of replication models were considered before the semiconservative nature of DNA replication was confirmed?

A. 1
B. 2
C. 3
D. 4
Answer» D. 4