In Protozoa like Amoeba and Paramecium, an organelle is found for osmoregulation which is

Options

A. contractile vacuole
B. mitochondria
C. nucleus
D. food vacuole

Explanation

**Step-by-Step Solution:**

1. **Understanding Osmoregulation**: Osmoregulation is the process by which organisms regulate the balance of water and solutes within their bodies. This is crucial for maintaining homeostasis, especially in environments where water availability can fluctuate.

2. **Identifying the Organisms**: The question mentions protozoans like Amoeba and Paramecium. These are single-celled organisms that live in aquatic environments and need to manage their internal water levels effectively.

3. **Identifying the Organelle**: The organelle responsible for osmoregulation in these protozoans is the contractile vacuole. This organelle helps to expel excess water that enters the cell, thus maintaining osmotic balance.

4. **Evaluating the Options**:
- **Contractile Vacuole**: This is indeed involved in osmoregulation by expelling excess water.
- **Mitochondria**: While important for energy production, mitochondria are not involved in osmoregulation and are absent in some protozoans like Amoeba.
- **Nucleus**: The nucleus is essential for storing genetic information and regulating cellular activities, but it does not play a role in osmoregulation.
- **Food Vacuole**: This organelle is responsible for storing and digesting food, not for regulating water balance.

5. **Conclusion**: Based on the evaluation of the options, the correct answer is the contractile vacuole, as it is specifically adapted for osmoregulation in protozoans like Amoeba and Paramecium.

**Final Answer**: The organelle found for osmoregulation in protozoa like Amoeba and Paramecium is the **contractile vacuole**.

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