Question

What is chemotropism ? Give one example. Name any two plant hormones and mention their functions.

Answer 1

The movement of a plant in response to a chemical stimulas is called chemotropism.For example, one of the chemotropism is the growth of pollen tubes towards ovules, being stimulated by sugarly substance secreted by the stigma, the style and the ovary.

Two plant hormones are:
(i) Auxins: promote cell elongation, root formation, and development of fruits.
(ii) Abscisic acid(ABA): retrads growth, promotes leaf and fruit fall and causes dormancy of seeds and bulbs.

Answer 2

The growth of a plant part due to chemical stimulus is known as chemotropism 'Chemotropism is growth of organisms such as bacteria and plants, navigated by chemical stimulus from outside of the organism or organism's part.

EX-For example, the growth of pollen tube towards the ovule in the ovary (through the stigma and style) is an example of positive chemotropism

There are several Plant Hormones classes, namely, Auxin, Cytokinin, Gibberellin, Abscisic Acid, Ethylene. Here are the functions of plant hormones in short. Functions of Auxin : Cell enlargement, apical dominance, prevention from bending; promote xylem differentiation, healing of wounds of plants.