Tropic movement is important due to following reasons :
(i) They- serve as a protective function and helps in developing a sudden response for a change.
(ii) Helps in growth and development of plants.
Seismonastic Movement: These movements are brought about by mechanical stimuli such as contact with a foreign body, fast wind and raindrops etc. These movements are seen in stigmas, stamens and leaves of many plants.
Photonastic Movement: There movements are induced by fluctuations in the intensity of light. Such movements are exhibited by flowers of several plants.
