Nerve cells are found in

Options

A. Hydra
B. Sycon
C. Paramecium
D. Amoeba.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where nerve cells are found among the given options: Hydra, Cycone, Paramecium, and Amoeba.

2. **Identifying the Organisms**:
- **Hydra**: A simple freshwater organism belonging to the phylum Cnidaria.
- **Cycone**: A type of sponge, which belongs to the phylum Porifera.
- **Paramecium**: A single-celled organism that falls under the group of ciliates.
- **Amoeba**: A single-celled organism known for its shape-shifting abilities, belonging to the group of protozoa.

3. **Analyzing Nerve Cell Presence**:
- **Hydra**: It has a simple nerve net that is spread throughout its body. These nerve cells are located at the base of the epithelial muscular cells and are responsible for receiving and transmitting information.
- **Cycone**: As a sponge, it lacks true nerve cells and operates through a simpler system of cell communication.
- **Paramecium**: This organism does not have nerve cells; it uses cilia for movement and has a different method of responding to stimuli.
- **Amoeba**: Similar to Paramecium, it does not possess nerve cells and relies on its cytoplasm for movement and response.

4. **Conclusion**: Based on the analysis, nerve cells are specifically found in Hydra among the options provided. Therefore, the correct answer is Hydra.

**Final Answer**: Nerve cells are found in Hydra.

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