In Hydra new nematocysts develop from

Options

A. Cnidocils
B. Glandular cells
C. Germ cells
D. Inerstitial cells.

Answer

**Step-by-Step Solution:**

1. **Understanding Nematocysts**: Nematocysts, also known as stinging cells, are specialized cells found in organisms like Hydra. They are responsible for delivering toxins to prey or threats.

2. **Identifying the Source of Nematocysts in Hydra**: In Hydra, new nematocysts develop from interstitial cells. These interstitial cells are unspecialized cells that have the potential to differentiate into various types of cells, including nematocysts.

3. **Function of Interstitial Cells**: When a nematocyst discharges its toxin, the interstitial cell that formed it becomes non-functional. However, interstitial cells can quickly migrate to the tentacles of Hydra and differentiate again into new nematocysts.

4. **Other Cell Types**: The other options provided (needle cells, glandular cells, and germ cells) do not have the ability to develop into nematocysts in Hydra. Therefore, they are not the correct answer.

5. **Conclusion**: The correct answer to the question "In Hydra, new nematocysts develop from" is interstitial cells.

**Final Answer**: Interstitial cells.

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