(c)How do tropisms differ from nasties (or nastic movements)?
Tropic movement |
Nastic movement |
1. The tropic movement shows the directional movement of a plant part with respect to the direction of the stimulus. |
1. The nastic movement shows the non-directional movement of the plant part with respect to the direction of the stimulus. |
2. All tropisms are growth movements but all nastic movements are not growth movements. |
2. Nastic movements may or may not be growth movements. |
3. The tropic movements of plants are induced by stimuli such as light, gravity, water, chemical, and touch. |
3. The nastic movements of plants are induced by stimuli such as heat, light, touch (or contact). |
4. Example: Bending of plant stem towards light. |
4. Example: The folding of leaves of a sensitive plant (Mimosa pudica) in response to touch. |