During DNA replication,strand separation by breaking the H-bonds in performed by

Options

A. Topoisomerase
B. Gyrase
C. Helicases
D. More than one option is correct.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which enzyme is responsible for separating the DNA strands by breaking the hydrogen bonds during DNA replication.

2. **Identifying the Options**: The options provided are:
- A) Topoisomerase
- B) Gyrase
- C) Helicases
- D) More than one option is gyrase

3. **Analyzing Topoisomerase**:
- Topoisomerase is an enzyme that helps in the unwinding of DNA strands. However, it does not break hydrogen bonds. Its primary role is to relieve the tension that builds up ahead of the replication fork.

4. **Analyzing Gyrase**:
- Gyrase is a type of topoisomerase that also helps in unwinding DNA. Like topoisomerase, gyrase does not break hydrogen bonds. Its function is similar to that of topoisomerase in relieving supercoiling ahead of the replication fork.

5. **Analyzing Helicases**:
- Helicases are the enzymes specifically responsible for unwinding the DNA double helix. They achieve this by breaking the hydrogen bonds between the complementary bases of the DNA strands, allowing the strands to separate.

6. **Conclusion**: Based on the analysis, the enzyme responsible for breaking the hydrogen bonds and separating the DNA strands during replication is **helicase**. Therefore, the correct answer is option C.

**Final Answer**: C) Helicases

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