Question

During DNA replication, the breaking of hydrogen bonds between two parental strands and their unwinding is catalyzed by _______ enzymes.

• A. Helicase
• B. Ligase
• C. Topoisomerase
• D. Polymerase

Hint:

Helicase unwinds the DNA at the replication fork, allowing DNA polymerase to copy the strands during replication.

Answer 1

The Correct Option is A

Step 1: The enzyme helicase is responsible for unwinding the DNA double helix by breaking the hydrogen bonds between the complementary strands during DNA replication.

Step 2:
- Ligase: Joins Okazaki fragments in lagging strand synthesis.
- Topoisomerase: Relieves supercoiling tension ahead of the replication fork.
- Polymerase: Synthesizes the new DNA strand.

Conclusion: Helicase is the enzyme that catalyzes the unwinding of DNA.