Extension of plasma membrane in prokaryotic cell is :

Options

A. mesosome
B. nucleoid
C. ribosome
D. none of these

Answer

To solve the question regarding the extension of the plasma membrane in prokaryotic cells, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Plasma Membrane**:
- The plasma membrane is a semi-permeable membrane that surrounds the cell, controlling the movement of substances in and out of the cell.

2. **Identifying Extensions of the Plasma Membrane**:
- In prokaryotic cells, the plasma membrane can extend into the cell itself. This extension is known as mesosome.

3. **Defining Mesosome**:
- Mesosomes are formed by the invagination (inward folding) of the plasma membrane. They can take various forms such as vesicles, tubules, or lamellae.

4. **Functions of Mesosomes**:
- Mesosomes play crucial roles in prokaryotic cells, including:
- Assisting in cell wall formation.
- Aiding in DNA replication during cell division.

5. **Conclusion**:
- Therefore, the extension of the plasma membrane in prokaryotic cells is called **mesosome**.

### Final Answer:
The extension of the plasma membrane in prokaryotic cells is **mesosome**.

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