In cloning vector pBR322, the Barn HI cloning site is found in which selectable marker gene?

Options

A. Ampicillin resistance gene
B. Tetracycline resistance gene
C. Chloramphenicol resistance gene
D. Lac Z gene

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the location of the BamHI cloning site in the cloning vector pBR322, specifically which selectable marker gene it is associated with.

2. **Identifying pBR322**: pBR322 is a well-known plasmid cloning vector that contains multiple features, including selectable marker genes that provide resistance to antibiotics.

3. **Selectable Marker Genes in pBR322**: The two primary selectable marker genes present in pBR322 are:
- Ampicillin resistance gene (bla)
- Tetracycline resistance gene (tet)

4. **Understanding BamHI Cloning Site**: The BamHI restriction site is a specific location on the plasmid where the DNA can be cut for cloning purposes.

5. **Analyzing the Options**: The options provided are:
- (a) Ampicillin resistance gene
- (b) Tetracycline resistance gene
- (c) Chloramphenicol resistance gene
- (d) lacZ gene

6. **Evaluating Each Option**:
- **Ampicillin resistance gene**: This gene provides resistance to ampicillin but does not contain the BamHI site.
- **Tetracycline resistance gene**: This gene is known to contain the BamHI cloning site.
- **Chloramphenicol resistance gene**: This gene does not contain the BamHI site.
- **lacZ gene**: This gene is involved in the metabolism of lactose and does not contain the BamHI site.

7. **Conclusion**: Based on the analysis, the BamHI cloning site is found in the **tetracycline resistance gene**.

**Final Answer**: The BamHI cloning site in the cloning vector pBR322 is found in the **tetracycline resistance gene**.

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