Movements of tentacles in Drosera are

Options

A. Photonastic
B. Thermonastic
C. Thigmonastic
D. Seismonastic.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the type of movements exhibited by the tentacles of the plant Drosera. Drosera is commonly known as the sundew plant, which is a carnivorous plant.

2. **Identifying the Function of Tentacles**: The tentacles of Drosera are specialized structures that respond to the presence of prey. When an insect or other small creature comes into contact with these tentacles, they exhibit movement.

3. **Analyzing the Options**:
- **Photonastic**: This term refers to movements in response to light. Since the tentacles of Drosera respond to touch rather than light, this option is incorrect.
- **Thermonastic**: This term refers to movements in response to temperature changes. The tentacles do not move in response to temperature, making this option incorrect as well.
- **Thigmonastic**: This term refers to movements in response to touch. Since the tentacles of Drosera move when they come into contact with prey, this option is correct.
- **Sysmonastic**: This term refers to movements in response to both touch and vibration. While this describes some plant movements, it does not specifically apply to the tentacles of Drosera, making this option incorrect.

4. **Conclusion**: Based on the analysis of the options, the correct answer is that the movements of the tentacles in Drosera are **Thigmonastic**.

**Final Answer**: The movements of tentacles in Drosera are Thigmonastic.

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