*The growth of a plant toward any stimulus is called tropism, and the growth of a plant toward a light stimulus is called phototropism.
*The growth of the parts of plants in response to the force of gravity is called
*The growth or turning of plant roots towards or away from moisture is called Hydrotropism
*Chemo-tropism is the growth of organisms (or parts of an organism, including individual cells) such as bacteria and plants, navigated by chemical stimulus from outside of the organism or organisms part.

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