Which of the following cell could/should exhibit a successful mating

Options

A. ` F^(+)` & HFr
B. F– & F–
C. HFr & HFr
D. ` F^(+)` & F-

Answer

To determine which cells could exhibit successful mating, we need to understand the process of bacterial conjugation and the roles of different cell types involved.

### Step-by-Step Solution:

1. **Understand the Types of Cells**:
- **F+ Cells**: These are bacterial cells that contain the fertility factor (F factor) on a plasmid, allowing them to donate genetic material.
- **F- Cells**: These cells do not have the F factor and are recipients of genetic material.
- **HFR Cells**: High-frequency recombination cells that have the F factor integrated into their chromosomal DNA, allowing them to transfer chromosomal genes along with the F factor during conjugation.

2. **Identify the Conjugation Process**:
- In conjugation, an F+ cell can connect to an F- cell through a structure called the pilus, forming a conjugation bridge.
- The F factor is transferred from the F+ cell to the F- cell, converting the F- cell into an F+ cell.

3. **Analyze the Options**:
- F+ and HFR: An F+ cell can mate with an F- cell, but HFR cells typically transfer chromosomal DNA along with the F factor, which may not result in a successful mating in the same way.
- Both F-: This cannot result in mating since both cells lack the F factor.
- Both HFR: HFR cells can transfer genes, but they do not mate in the traditional sense as F+ and F- do.
- F+ and F-: This is the classic successful mating scenario where the F+ cell transfers the F factor to the F- cell.

4. **Conclusion**:
- The successful mating occurs between F+ and F- cells, where the F factor is transferred, resulting in the conversion of the F- cell to an F+ cell.

### Final Answer:
The cells that could exhibit successful mating are **F+ and F- cells**.

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