In pBR 322, how many recognition sites are present ?

Options

A. 8
B. 7
C. 3
D. 4

Explanation

To determine the number of recognition sites present in the plasmid pBR322, we can follow these steps:

### Step-by-Step Solution:

1. **Identify pBR322**:
- pBR322 is a plasmid that is widely used as a cloning vector in E. coli. It was one of the first plasmids developed for this purpose.

2. **Understand Recognition Sites**:
- Recognition sites are specific sequences of DNA where restriction enzymes can cut. These sites are crucial for cloning as they allow the insertion of foreign DNA into the plasmid.

3. **Count the Recognition Sites**:
- pBR322 contains a total of **8 recognition sites** for different restriction enzymes.

4. **List the Recognition Sites**:
- The specific recognition sites in pBR322 are:
1. Pvu II
2. Pst I
3. Pvu I
4. Eco RI
5. Cla I
6. Hind II
7. Bam HI
8. Sal I

5. **Conclusion**:
- Therefore, the answer to the question is that pBR322 has **8 recognition sites**.

### Final Answer:
pBR322 has **8 recognition sites**.

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