Question

Which plant hormone promotes apical dominance?

• A. Gibberellin
• B. Cytokinin
• C. Auxin
• D. Ethylene

Hint:

If the apical bud is removed, auxin supply decreases, and lateral buds start growing, leading to bushier plants.

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
Apical dominance is a condition where the central stem of the plant grows more vigorously than the lateral (side) branches. We need to identify the hormone responsible for this growth pattern.
Step 2: Detailed Explanation:
Auxin (specifically Indole-3-acetic acid or IAA) is produced in the shoot apical meristem (the tip of the plant).
It travels downward and inhibits the growth of axillary buds (lateral buds).
This ensures that the plant grows vertically towards the light source.
If the shoot tip is removed (decapitation), the source of auxin is lost, allowing lateral buds to grow and making the plant bushier.
Step 3: Final Answer:
The plant hormone is Auxin.