tropism

tro·pism   (trō'pĭz'əm)    n.  The turning or bending movement of an organism or a part toward or away from an external stimulus, such as light, heat, or gravity. [From -tropism.] tro'pic, tro·pis'tic adj., tro·pis'ti·cal·ly adv.

tropism 

Main Entry: tro·pism
Pronunciation: 'trO-"piz-&m
Function: noun
: involuntary orientation by an organism or one of its parts that involves turningor curving by movement or by differential growth and is a positive or negative response to a source of stimulation; also : a reflex reaction involving a tropism —tro·pis·tic /trO-'pis-tik/ adjective

tropism tro·pism (trō'pĭz'əm)
n.
The turning or bending movement of a living organism or part toward or away from an external stimulus, such as light, heat, or gravity.

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tro'pic, tro·pis'tic adj.

tropism   (trō'pĭz'əm)  Pronunciation Key  The growth or movement of a living organism or anatomical structure toward or away from an external stimulus, such as light, heat, or gravity. See also geotropism, hydrotropism, phototropism. tropistic adjective

tropism

response or orientation of a plant or certain lower animals to a stimulus that acts with greater intensity from one direction than another. It may be achieved by active movement or by structural alteration. Forms of tropism include phototropism (response to light), geotropism (response to gravity), chemotropism (response to particular substances), hydrotropism (response to water), thigmotropism (response to mechanical stimulation), traumatotropism (response to wound lesion), and galvanotropism, or electrotropism (response to electric current). Most tropic movements are orthotropic; i.e., they are directed toward the source of the stimulus. Plagiotropic movements are oblique to the direction of stimulus. Diatropic movements are at right angles to the direction of stimulus.

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