For a proper response to a stimulus, many organs in the body should work together.The working together of various organs in an organism to produce a proper response to a stimulus is called coordination.
In plants control and coordination is done by chemical substances called plant hormones or phytohormones.
There are five main types of plant hormones.They are:-
Auxin - help in cell division, cell elongation and growth.
Gibberellins-help in the growth of stem and branches.
Cytokinins-help in cell division, formation of fruits and seeds.
Abscisic acid - inhibits growth and affects wilting of leaves and;
Ethylene-helps in flowering and ripening of fruits