What are precursors and bound auxins ?

Explanation

**Step-by-Step Solution:**

1. **Definition of Auxins**:
- Auxins are a class of plant hormones that play a crucial role in regulating various aspects of plant growth and development, including apical dominance (the phenomenon where the main central stem of the plant grows more vigorously than the side stems) and stem elongation.

2. **Understanding Precursors**:
- Precursors are the initial compounds or substances that are transformed into auxins through biochemical processes within the plant. They serve as the building blocks for the synthesis of auxins.

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