向こう性せい

noun

tropism

Biological term for directional growth or movement of an organism in response to an external stimulus, such as light or gravity.

• 植しょく物ぶつの光ひかりに向むかう成せい長ちょうは、光ひかり向こう性せいと呼よばれる。

  The growth of plants toward light is called phototropism.