State the names of plant hormones and their effects.

Explanation

Plant hormones : They help to coordinate growth, development and response to environment.
They are synthesised at places away from where they act and simply diffuse to the area of action.
(i) Growth promoting hormones :
(1) Auxin : It is synthesised at the shoot tip. It helps cells to grow longer. When light is coming from one side of the plant, auxin diffuses towards the side of the shoot which is in shade. Specific concentration of auxin stimulates the cells to grow longer on the side of the shoot which is away from light. Thus plant appears to bend towards light. The auxin is responsible for phototropism.
(2) Gibberellin : It helps in the growth of the stem.
(3) Cytokinin : It is naturally present in higher concentration in areas where rapid cell division occurs. In fruits and seeds, it is found in more concentration. It promotes cell division.
(ii) Growth inhibiting hormone
Abscisic acid : It inhibits plant growth. Its effects include wilting of leaves.