Page 258 - Biology_F5

Coordination and Irritability

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(a) (b)

Figure 4.38: Nastic movement in flower (a) during the day the flower opens and (b) during the night
the flower closes

Seismonasty between different sides of the plant part.
This is the movement of plant parts For example, changes in the water contents
in response to touch. Seismonastic of the tissues at the base of the leaf of the
movement is also known as thigmonastic Mimosa plant change in the shrinkage
movement. An example of seismonastic and folding of its leaflets. Such response
movement is folding of leaves of Mimosa may be due to different stimuli, such as
pudica in response to touch (Figure 4.39). light, touch, heat, or electric shock. After a
suitable recovery period, the leaflets open
Generally, nastic movement can result again. Normally, they remain expanded
from changes in turgor or growth rate during the day while closed at night.

Figure 4.39: Nastic movement in the leaflets of the Mimosa plant

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