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Could someone help me in my project?It is about 7 nastic movements with two examples...
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- Photonasty - response to light. Examples: Vertical growth of plants towards light source; Change in orientation of cannabis leaves (from horizontal to vertical) during sun down.
- Nyctinasty - reponse to dark, or night. Examples: Closing/Opening of daisies and cloves at night/morning; Sleep movements of the leaves of legumes.
- Chemonasty - response to chemical stimulus. Examples: Closing/Bending of glandular hairs of sundew in response to nitrogenous compounds from an insect to prevent the escape of such insect; Movement of roots towards the more nutrient-rich parts of the soil.
- Hydronasty - response to water. Examples: Movement of roots towards water source, like near the river; Opening/Closing of dandelions in response to humidity (water in the atmosphere).
- Thermonasty - response to temperature. Examples: Opening of tulips when the temperature is increasing and closing when temperature is decreasing, which serves to protect pollens when snow/rain falls; Growth of tomatoes is better when temperature is alternating (night/day) than when temperature is kept constant (all night / all day).
- Geonasty - response to gravity. Examples: Bending of long leaves or barks (when the strength of the plant is not enough to support them against gravity); The upward growth of a plant (against gravity) and generally downward movement of roots (with gravity).
- Thigmonasty - response to contact. Examples: Closing of Mimosa pudica(also known as the touch-me-not plant) in response to touch/contact; Closing of the venus fly trap in response to movement, usually due to landing of insects, to capture the insect.
(Level 1) Associate Educator, Expert
Nastic movements are responses (usually of but not limited to plants) to stimuli. Unlike trophisms, these are not dependent on the direction of the stimulus.
Posted by mvcdc on August 18, 2013 at 11:51 AM (Answer #1)
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