RESPONSE AND COORDINATION IN PLANTS Plants movements Tropic movement:- The movements of organism in the direction of stimulus or away from stimulus are known as tropic movement or tropism. It is positive if directed towards the source of stimulus and negative if directed away from stimulus. Different types of tropic movements:- Phototropism:- The tropic response of organism to light is called phototropism. If a young green plant takes light from one direction only, it bends towards the light source. So, the stem said to be positively phototropic. Geotropism:- The tropic response of organism to gravity s called geotropism. If a growing region of plant placed horizontally, the stems tips grow away from pull of gravity while the root grows in direction of gravity. The stem is negatively geotropic and the root is said to be positively geotropic. ...
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