Question

Explain coordination in plants with the help of suitable examples.

Answer 1

Since plants do not have nervous and muscular systems like animals, coordination in plants occurs in response to particular stimuli. Tropism/tropic movement is the term used for the movement or growth of any plant part in response to an external stimulus.

These tropic movements can be of various types like:

1. Phototropic movement: The shoot system of any plant responds to the light stimulus i.e. it grows towards the source of light. The movement shown by plants towards the source of light is called ‘Phototropic movement’.
2. Gravitropic movement: The root system of plants responds to stimuli like gravitation and water. These responses are called ‘gravitropic movement’
3. Hydrotropic movement: The root system of plants responds to stimuli like water. These responses are called  ‘hydrotropic movement’.
4. Chemotropic movement: Movement shown by plants in response to specific chemicals is called ‘chemotropic movement’. For exmaple, the growth of the pollen tube towards the ovule.

Each of the above mentioned activities is associated with the growth of plants, hence it is called activities related to their growth. The growth and development process of plants is not related to development. Various types of action are created in the surrounding environment by stimulating vegetation. They use electrical and chemical stimuli, such as mimosa. The amount of water in plant cells is increased or decreased, due to which their shape changes and the formation of activity takes place.