1 Auxin is directly or indirectly responsible for apical dom

1. Auxin is directly or indirectly responsible for apical dominance in plants. In this phenomenon, the growth of lateral or axillary buds is inhibited by auxin that moves down the stem from the apical meristem. It has long been the practice of horticulturists to clip off the apical mersitems of certain young houseplants. What impact should this practice have on subsequent plant growth and appearance?

2. What adaptive role would positive phototropism play in a natural ecosystem where plants are crowded?

Solution

1).

The phenomenon of central stem domination over the other side stems and the domination of side stems over its side branches is known as “apical dominance.” When the apical meristems are clipped off, it interferes with the apical dominance. As a result, the growth if central stem is supressed, which favours the growth of side stems by releasing the cytokines. Thus, the plant becomes more widen then its height.