Auxin develops at the tip of the stem. Its movement is largely

Options

A. Acropetal
B. Centropetal
C. Basipetal
D. Acropetal and basipetal.

Answer

### Step-by-Step Solution:

1. **Understanding Auxin**: Auxin is a plant hormone that plays a crucial role in regulating plant growth. It is primarily produced in the meristematic tissues, which are located at the tips of the roots and stems.

2. **Location of Auxin Production**: Auxin is synthesized at the tip of the stem (shoot apex) and the root (root apex). This is important because the location influences its movement within the plant.

3. **Types of Movement**: Auxin can move in two main directions:
- **Acropetal Movement**: This refers to the movement of auxin from the base of the plant towards the apex (tip). This type of movement is observed when auxin is produced at the root tip and moves upwards to the shoot apex.
- **Basipetal Movement**: This is the movement of auxin from the apex (tip) downwards towards the base of the plant. This occurs when auxin is produced at the shoot apex and moves downwards.

4. **Analyzing the Question**: The question specifically asks about auxin that develops at the tip of the stem. Since auxin produced at the tip of the stem will move downwards towards the base, this indicates a basipetal movement.

5. **Conclusion**: Therefore, the correct answer to the question is that the movement of auxin, when it develops at the tip of the stem, is largely **basipetal**.

### Final Answer:
The movement of auxin that develops at the tip of the stem is largely **basipetal**.

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