Question

question 64
what is the function of topoisomerase?
○ relieving strain in the dna ahead of the replication fork
○ elongating new dna at a replication fork by adding nucleotides to the existing chain
○ adding methyl groups to bases of dna
○ unwinding of the double helix

Explanation:

To determine the function of topoisomerase, we analyze each option:

• Option 1: Topoisomerase relieves the torsional strain (supercoiling) that arises in the DNA ahead of the replication fork as the double helix is unwound.
• Option 2: DNA polymerase is responsible for elongating new DNA by adding nucleotides, not topoisomerase.
• Option 3: Enzymes involved in DNA methylation (like DNA methyltransferases) add methyl groups, not topoisomerase.
• Option 4: Helicase is the enzyme that unwinds the double helix, not topoisomerase.

Answer:

A. relieving strain in the DNA ahead of the replication fork