Bacterial mesosomes are functional substitute of

Options

A. Dictyosome
B. Mitochondria
C. E.R.
D. Nucleous

Answer

To solve the question "Bacterial mesosomes are functional substitutes of," we will analyze each option provided and determine the correct answer.

### Step-by-Step Solution:

1. **Understanding Bacterial Mesosomes**:
- Mesosomes are infoldings of the plasma membrane in bacteria. They are believed to be involved in various cellular processes, particularly respiration.

2. **Analyzing the Options**:
- **Option 1: Dictyosome**:
- Dictyosomes (or Golgi apparatus in eukaryotes) are involved in the modification, sorting, and packaging of proteins. They are not involved in respiration.
- **Conclusion**: This option is incorrect.

- **Option 2: Mitochondria**:
- Mitochondria are the organelles responsible for respiration in eukaryotic cells. However, bacteria do not have mitochondria; instead, they perform respiration through mesosomes.
- **Conclusion**: This option is correct as mesosomes serve a similar function in bacteria.

- **Option 3: Endoplasmic Reticulum**:
- The endoplasmic reticulum (ER) is involved in protein synthesis and transport. It does not play a role in respiration.
- **Conclusion**: This option is incorrect.

- **Option 4: Nucleolus**:
- The nucleolus is primarily involved in the synthesis of ribosomal RNA and does not have a role in respiration.
- **Conclusion**: This option is incorrect.

3. **Final Answer**:
- Based on the analysis, the correct answer is **Option 2: Mitochondria**. Bacterial mesosomes are functional substitutes for mitochondria in the context of respiration.