AP BIOLOGY

Detailed explanation-1: -Tropic movements are directional responses to stimuli while nastic movements are non-directional responses to stimuli.

Detailed explanation-2: -Tropisms are directional growth responses to a stimulus. In plants, tropisms can be phototropic in response to light, hydrotropic in response to water, or gravitropic in response to gravity. Shoots and roots respond differently to the stimuli, and this is influenced by the plant growth hormone auxin.

Detailed explanation-3: -A tropism is directional growth in response to a stimulus. A positive tropism occurs when a plant (or a part of the plant) grows towards the stimulus, and a negative tropism is growth away from the stimulus.

Detailed explanation-4: -Tropism is when a plant moves in response to an external stimulus in the environment. Positive tropism is when a plant moves towards a stimulus. Negative tropism is when a plant moves away from a stimulus.