Trichocysts occur in

Options

A. Liver Fluke
B. Bladderworm
C. Paramecium
D. Hydra.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where trichocysts occur. Trichocysts are specialized structures found in certain organisms.

2. **Identifying Trichocysts**: Trichocysts are thin, hair-like structures that serve a defensive or offensive function. They can be ejected from the cell when the organism is threatened by predators.

3. **Analyzing the Options**: The options provided are liver, fluke, bladder, worm, paramecium, and hydra. We need to determine which of these organisms contains trichocysts.

4. **Evaluating Each Option**:
- **Liver**: Not applicable as it is an organ, not an organism.
- **Fluke**: Flukes are parasitic flatworms and do not have trichocysts.
- **Bladder**: This is also not an organism but an organ.
- **Worm**: While some worms have specialized structures, they do not have trichocysts.
- **Paramecium**: This is a unicellular organism that is known to have trichocysts.
- **Hydra**: Hydra is a multicellular organism and does not possess trichocysts.

5. **Conclusion**: Based on the analysis, the only organism from the options that contains trichocysts is **Paramecium**.

**Final Answer**: Trichocysts occur in **Paramecium**.

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