tropism

n. a form of orientation observed in both plants and nonhuman animals toward or away from a stimulus, such as sunlight or gravity. The flower of a plant may turn gradually to face the sun as it moves across the sky (heliotropism), while its roots follow magnetic lines of force and the pull of gravity. Tropism contrasts with taxis, which is a directed movement toward or away from a stimulus. Compare kinesis. —tropic adj.

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Psychology term of the day

May 8th 2024

drug tolerance

see tolerance.