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phototropism

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noun pho·tot·ro·pism \fō-ˈtä-trə-ˌpi-zəm\

Definition of phototropism

  1. :  a tropism in which light is the orienting stimulus



Origin of phototropism

International Scientific Vocabulary


First Known Use: 1899


Medical Dictionary

phototropism

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noun pho·tot·ro·pism \fō-ˈtä-trə-ˌpiz-əm, ˌfōt-ō-ˈtrō-ˌpiz-əm\

Medical Definition of phototropism

  1. :  a tropism in which light is the orienting stimulus—see heliotropism

  2. 2:  the reversible change in color of a substance produced by the formation of an isomeric modification when exposed to radiant energy (as light)




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