Sex plasmid occurs in

Options

A. Recipient bacteria
B. Donor bacteria
C. Bacteriophage
D. Diplococus

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the occurrence of sex plasmids in certain types of bacteria. We need to identify which option correctly states where sex plasmids are found.

2. **Analyzing the Options**:
- **Option 1: Recipient Bacteria**: This option suggests that sex plasmids are found in recipient bacteria. However, during the process of conjugation, the recipient bacteria do not possess sex plasmids; they receive genetic material from the donor.

- **Option 2: Donor Bacteria**: This option states that sex plasmids occur in donor bacteria. This is correct because sex plasmids are responsible for the transfer of genetic material during conjugation, and they are found in the donor bacteria.

- **Option 3: Bacteriophage**: This option refers to bacteriophages, which are viruses that infect bacteria. They do not possess sex plasmids, so this option is incorrect.

- **Option 4: Diplococcus**: This option mentions Diplococcus, which is a genus of bacteria. However, it does not specifically relate to the presence of sex plasmids, making this option incorrect.

3. **Conclusion**: After analyzing all the options, we conclude that sex plasmids occur in **donor bacteria**. Therefore, the correct answer is **Option 2: Donor Bacteria**.

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