The number of bp in each turn of B-DNA helix is

Options

A. 1
B. 10
C. 20
D. 5

Answer

**Step-by-Step Solution:**

1. **Understanding B-DNA Structure**:
- B-DNA is one of the most common forms of DNA, characterized by its right-handed helical structure. It was first described by James Watson and Francis Crick.

2. **Identifying Key Characteristics**:
- The diameter of B-DNA is approximately 20 angstroms.
- It has a specific number of base pairs per helical turn, which is crucial for answering the question.

3. **Base Pairs per Turn**:
- In the B-DNA structure, there are 10 base pairs in each complete turn of the helix. This is a fundamental characteristic of B-DNA.

4. **Conclusion**:
- Based on the characteristics of B-DNA, the answer to the question regarding the number of base pairs in each turn of the B-DNA helix is 10.

5. **Final Answer**:
- Therefore, the correct option is **10 base pairs**.

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