The movement of plant organs in response to force of gravity is called

Options

A. Phototropism
B. Thigmotropism
C. Geotropism
D. Chemotropism.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term that describes the movement of plant organs in response to the force of gravity.

2. **Identifying the Options**: The options provided are:
- A) Phototropism
- B) Thigmotropism
- C) Geotropism
- D) Chemotropism

3. **Analyzing Each Option**:
- **Phototropism**: This refers to the movement of plants in response to light. Since the question is about gravity, this option is incorrect.
- **Thigmotropism**: This is the movement of plants in response to touch or contact with a solid object. Again, this does not relate to gravity, making this option incorrect.
- **Geotropism**: This term specifically refers to the movement of plant parts in response to gravitational pull. This aligns perfectly with the question, indicating that this is the correct answer.
- **Chemotropism**: This describes the movement of plants in response to chemical stimuli. Since this does not involve gravity, this option is also incorrect.

4. **Conclusion**: After analyzing all the options, the correct answer to the question is **Geotropism** (Option C), as it directly relates to the movement of plant organs in response to gravity.

**Final Answer**: The movement of plant organs in response to the force of gravity is called **Geotropism**.

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