Tropism: Quick Facts

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Photos and Videos

Tropism (Top) Phototropism shown in the multiple exposure of a fungus fruiting body; (bottom) geotropism shown in the multiple exposure of oat coleoptiles.

Examine the role of sunlight and gravity in phototropic and geotropic plant growth

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Topics

orthotropism chemotropism diatropism Do sunflowers really follow the Sun?gravitropism galvanotropism hydrotropism traumatotropism thigmotropism plagiotropism plant development photosynthesis plant reproductive system Plant cell nectar growth ring angiosperm fern bryophyte conifer

Key People

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Julius von Sachs

German botanist

Jacques Loeb

Jacques Loeb

German biologist