Explore topic-wise MCQs in Biochemistry.

This section includes 20 Mcqs, each offering curated multiple-choice questions to sharpen your Biochemistry knowledge and support exam preparation. Choose a topic below to get started.

1.

Which type of supercoiling takes the form of extended right-handed coils?

A. Plectonemic supercoiling
B. Solenoidal supercoiling
C. Negative supercoiling
D. Positive supercoiling
Answer» B. Solenoidal supercoiling
2.

Under-winding is measured in terms of ____________

A. Supercoiling
B. Linking difference
C. Positive supercoiling
D. Negative supercoiling
Answer» C. Positive supercoiling
3.

The type I enzyme(s) is/are ____________

A. Topoisomerases I and III
B. Topoisomerases II
C. Topoisomerase IV
D. Topoisomerases I and IV
Answer» B. Topoisomerases II
4.

The type of topoisomerases that can introduce negative supercoils is ____________

A. Type I
B. Type II
C. Type III
D. Type IV
Answer» C. Type III
5.

The type of topoisomerases which generally relaxes DNA by removing negative supercoiling?

A. Type I
B. Type II
C. Type III
D. Type IV
Answer» B. Type II
6.

The enzyme responsible for the removal of supercoiling in replicating DNA ahead of the replication fork is ____________

A. Topoisomerase
B. Primase
C. DNA polymerase
D. Helicase
Answer» B. Primase
7.

Changing twist from the relaxed state requires adding energy and increases the ____________

A. Forces in molecule
B. Stress along molecule
C. Strain over molecule
D. None of the above
Answer» C. Strain over molecule
8.

Over-twisting of a molecule results in ____________

A. Negative supercoiling
B. Positive supercoiling
C. Elongation
D. Compression
Answer» C. Elongation
9.

When there is no net bending of the DNA axis upon itself, the DNA is said to be in a ____________

A. Elongated state
B. Compressed state
C. Relaxed state
D. Denatured state
Answer» D. Denatured state
10.

The phenomenon of twisting around itself by a molecule to relieve helical stress is ____________

A. Supercoiling
B. Coiling
C. Elongation
D. Compression
Answer» B. Coiling
11.

UNDER-WINDING_IS_MEASURED_IN_TERMS_OF?$

A. Supercoiling
B. Linking difference
C. Positive supercoiling
D. Negative supercoiling
Answer» C. Positive supercoiling
12.

Which type of supercoiling takes the form of extended right-handed coils?$

A. Plectonemic supercoiling
B. Solenoidal supercoiling
C. Negative supercoiling
D. Positive supercoiling
Answer» B. Solenoidal supercoiling
13.

The type I enzyme(s) is/ar?

A. Topoisomerases I and III
B. Topoisomerases II
C. Topoisomerase IV
D. Topoisomerases I and IV
Answer» B. Topoisomerases II
14.

The type of topoisomerases that can introduce negative supercoils is

A. Type I
B. Type II
C. Type III
D. Type IV
Answer» C. Type III
15.

The type of topoisomerases which generally relaxes DNA by removing negative supercoiling is

A. Type I
B. Type II
C. Type III
D. Type IV
Answer» B. Type II
16.

The enzyme responsible for the removal of supercoiling in replicating DNA ahead of the replication fork is

A. Topoisomerase
B. Primase
C. DNA polymerase
D. Helicase
Answer» B. Primase
17.

Changing twist from relaxed state requires adding energy and increases the

A. Forces in molecule
B. Stress along molecule
C. Strain over molecule
D. None of the above
Answer» C. Strain over molecule
18.

Over-twisting of a molecule results in

A. Negative supercoiling
B. Positive supercoiling
C. Elongation
D. Compression
Answer» C. Elongation
19.

When there is no net bending of the DNA axis upon itself, the DNA is said to be in a

A. Elongated state
B. Compressed state
C. Relaxed state
D. Denatured state
Answer» D. Denatured state
20.

The phenomenon of twisting around itself by a molecule to relieve helical stress is

A. Supercoiling
B. Coiling
C. Elongation
D. Compression
Answer» B. Coiling