A special membranous structure mainly associated with respiration secretion process and replication is

Options

A. Mesosomes
B. Plasmids
C. Chromatophores
D. Ribosomes

Answer

To answer the question, "A special membranous structure mainly associated with respiration, secretion process, and replication is," we will analyze the given options step by step.

### Step-by-Step Solution:

1. **Understanding the Question**: We need to identify a membranous structure that plays a significant role in respiration, secretion, and replication.

2. **Evaluating the Options**:
- **Mesosomes**: These are extensions of the plasma membrane found in prokaryotic cells. They are involved in various cellular processes, including respiration, secretion, and replication. Therefore, they are a strong candidate.
- **Plasmids**: These are small, circular DNA molecules found in bacteria. While they are involved in replication, they do not play a role in respiration or secretion. Hence, they cannot be the correct answer.
- **Chromatophores**: These are pigment-containing structures found mainly in eukaryotic cells, involved in photosynthesis. They are not associated with respiration or secretion, making them an incorrect option.
- **Ribosomes**: These are cellular structures responsible for protein synthesis. They do not participate in respiration, secretion, or replication, so they are not the correct answer.

3. **Conclusion**: After evaluating all the options, mesosomes are the only structures that are involved in respiration, secretion, and replication. Therefore, the correct answer is **mesosomes**.

### Final Answer:
The special membranous structure mainly associated with respiration, secretion process, and replication is **mesosomes**.

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