Entwining of Grape Vine tendril around a suppot is

Options

A. Thigmotropism
B. Nutation
C. Gravitropism
D. Chemonasty.

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks about the phenomenon where grapevine tendrils entwine around a support. This is a specific type of plant movement.

2. **Identifying the Options**: The options provided are:
- Thigmotropism
- Mutation
- Gravitropism
- Chemonasty

3. **Defining Each Term**:
- **Thigmotropism**: This is a directional growth movement in response to touch stimuli. It is commonly observed in climbing plants and tendrils.
- **Mutation**: This refers to changes in the genetic material of an organism, which does not relate to movement.
- **Gravitropism (or Geotropism)**: This is the growth movement of a plant in response to gravity, such as roots growing downwards.
- **Chemonasty**: This is a movement in response to chemical stimuli, not touch.

4. **Analyzing the Correct Answer**: Since grapevine tendrils wrap around supports due to a response to touch, the correct term that describes this behavior is **Thigmotropism**.

5. **Conclusion**: Therefore, the correct answer to the question is **Thigmotropism**.

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