plant responses

tropism response

irreversible response

it is a growth response to an external stimulus

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negative tropism

positive tropism

nastic

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reversible

can be repeated

growth away from the direction of the stimulus

Nastic movements are caused by a change in water pressure in the leaf cells

growth in the direction of the stimulus

Once the stimulus ends, the leaves return to their original positions.

types of tropism

thigmotropism.

gravitropism

phototropism,

example: the closing
of a Venus flytrap’s leaves

it is the growth in the direction of the light

is the growth response to gravity

is the growth response to a mechanical stimulus

the auxin aides in this process by the unequal distribution resulting to the curve of the stem towards the source of light

there is a negative gravitropism in the stems of the plants as the grow in the opposite direction

causes movement that is not dependent on the direction of the stimulus

there is a positive response of gravitropism in the roots as they grow in the same direction as the stimulus