Q.The affect of apical dominance can be overcome by which of the following hormone:

Apical Dominance: Why the Top Bud Hogs the Show

Imagine a young plant — a sapling or a tomato seedling. It has a single main stem growing upward, with a bud at the very tip (the apical bud) and smaller buds tucked in the axils of each leaf (the lateral buds). If you leave the plant alone, the apical bud grows vigorously upward, while those lateral buds stay dormant, doing nothing. But if you pinch off the tip — say a gardener prunes the top — suddenly those side buds burst into life, producing branches.

That is apical dominance in action: the suppression of lateral bud growth by the actively growing shoot apex.

The phenomenon is not a mystery — it is a controlled, chemical decision made by the plant. The apical bud produces a hormone called auxin (specifically IAA, indole-3-acetic acid). Auxin moves downward from the tip through the stem. As it travels, it actively inhibits the growth of the lateral buds. As long as the tip is intact and producing auxin, the side buds stay asleep.

The practical consequence is that the plant grows tall and straight, not bushy. This is an advantage in nature — it helps the plant outcompete neighbours for sunlight. But in agriculture and horticulture, we break apical dominance deliberately. When you prune the tip of a plant, you remove the source of auxin. The lateral buds are released from inhibition, and the plant becomes bushier. That is why you pinch the tops of marigolds or chillies to get more flowers and fruits.

So the core idea is simple: the tip dominates because it sends a chemical signal that tells the sides to wait. Remove the tip, and the sides get their turn.

This is a core NCERT Class 11 Biology concept from Plant Growth and Development, and it appears in CBSE and NEET Biology question banks under searches like 'Apical Dominance: Definition, Diagram & Examples' and 'Apical Dominance notes class 11'. The classic decapitation experiment (removing the shoot tip) used to demonstrate apical dominance is a common practical-based question.