Mesosomes are found in :-

Options

A. Fungi
B. Virus
C. Mycoplasma
D. Bacteria

Answer

**Step-by-Step Solution:**

1. **Understanding Mesosomes**: Mesosomes are structures found in certain types of cells. They are formed by the folding of the bacterial cell membrane.

2. **Comparing with Eukaryotic Structures**: Mesosomes are often compared to mitochondria in eukaryotic cells because they are involved in similar functions, such as respiration.

3. **Function of Mesosomes**: Mesosomes are rich in enzymes and play a role in increasing the surface area of the cell membrane, which is beneficial for various cellular processes, including respiration.

4. **Identifying Organisms**: Now, we need to determine which of the given options (fungi, virus, mycoplasma, or bacteria) contains mesosomes.

5. **Analyzing the Options**:
- **Fungi**: Fungi are eukaryotic organisms and do not have mesosomes.
- **Virus**: Viruses are acellular and do not possess any cellular structures like mesosomes.
- **Mycoplasma**: Mycoplasma are bacteria that lack a cell wall, but they do not have mesosomes.
- **Bacteria**: Mesosomes are specifically found in bacteria, as they are a feature of their cell membrane.

6. **Conclusion**: Based on the analysis, mesosomes are found in bacteria.

**Final Answer**: Mesosomes are found in bacteria.

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