Question

Name any two plant hormones and state their functions.

Answer 1

There are several types of hormones which stimulate or inhibits the growth of plants. Auxin and gibberellins are the two growth hormones of the plant.
Functions of Auxin:
(1) Cell enlargement: Auxin causes cell enlargement by solubilisation of carbohydrates, loosening of cell wall micro-fibrils, synthesis of new wall material and an increase in respiration.
(2) Prevention of lodging: Lower inter-nodes of the stem of cereals are long and weak. As a result, the plant bends down or droops.
Functions of Gibberellin:
(1) In bolting: In rosette forming plants, inter-nodes growth is poor but large leaves appear to rise arise in tufts. The inter-nodes suddenly elongate and the stem becomes normal just before flowering. This is called bolting.
(2) Parthenocarpy: Gibberellins have been found to be effective in inducing parthenocarpy in tomatoes, apple, etc.