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Questions
Distinguish between tropic movements and nastic movements in plants. Give examples to illustrate your answer.
How do tropisms differ from nasties (or nastic movements)?
Solution 1
| Tropic movements | Nastic movements |
| These are directional movements of plants in response to stimulus. | These are non-directional movements of plants in response to stimulus. |
| Example: The upward growth of a plant stem in response to sunlight. | Example: The folding up of leaves in response to touch. |
Solution 2
| Tropism | Nasties |
| Tropisms are the directional movement of plant parts in response to an external stimulus. | Nasties are the non-directional movements of plant parts in response to an external stimulus. |
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