Question

What are tropic movements or tropism in plants?

Answer 1

A tropism is a biological phenomenon, indicating growth or turning movement of a biological organism, usually a plant, in response to an environmental stimulus.Tropisms are directional movement responses that occur in response to a directional stimulus.
Positive tropism = the plant, or a part of it, grows in the direction from which the stimulus originates.
Negative tropism = growth away from the stimulus.

Light = phototropism
Stems are positively phototropic.
Roots are negatively phototropic.
Gravity = gravitropism
Stems are negatively gravitropic while
roots are positively gravitropic.