Tropism K-12 Experiments
Tropism Background
Tropism Movies
Tropism Background
A tropism is a biological phenomenon, indicating growth or turning movement of a biological organism, usually a plant, in response to an environmental stimulus.
In tropisms, this response is dependent on the direction of the
stimulus (as opposed to nasties which are non-directional responses).
The word tropism comes from the Greek tropos ("to turn"). Tropisms are usually named for the stimulus involved (for example, a phototropism is a reaction to light) and may be either positive (towards the stimulus) or negative (away from the stimulus).
Tropisms are typically associated with plants (although not necessarily restricted to them). Where an organism is capable of directed physical movement (motility), movement or activity in response to a specific stimulus is more likely to be regarded by behaviorists as a taxis (directional response) or a kinesis (non-directional response).
In English, the word tropism is used in sometimes derisive
way to indicate an action done without cognitive thought: However,
"tropism" in this sense has a proper, although non-scientific, meaning
as an innate tendency, natural inclination, or propensity to act in a
certain manner.
Types of tropisms
See also
This article is licensed under the GNU Free Documentation License. It uses material from Wikipedia Encyclopedia article "Tropism"
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