Mesosome is the xtension of plasma membrane into the cell it helps in

Options

A. cell wall formation
B. DNA replication
C. respiration
D. all of the above

Answer

### Step-by-Step Solution:

1. **Definition of Mesosome**:
- Mesosome is defined as an extension of the plasma membrane into the cytoplasm of a bacterial cell. It is a unique structure primarily found in gram-positive bacteria.

2. **Structure of Mesosome**:
- Mesosomes appear as folds or invaginations of the plasma membrane. They increase the surface area of the membrane, which is beneficial for various cellular processes.

3. **Functions of Mesosome**:
- **Cell Wall Formation**: Mesosomes play a crucial role in the synthesis and maintenance of the cell wall in bacteria.
- **DNA Replication**: They are involved in the process of DNA replication, helping in the segregation of genetic material during cell division.
- **Respiration**: Mesosomes are also associated with cellular respiration, as they contain enzymes that facilitate this process.

4. **Conclusion**:
- Therefore, mesosomes are multifunctional structures that assist in cell wall formation, DNA replication, and respiration in bacteria.