AP BIOLOGY

Detailed explanation-1: -Geotropism is a type of tropism where plants show some growth in response to gravity. Roots growing downwards is an example of geotropism.

Detailed explanation-2: -Plants respond to their environment in a variety of ways. The response of an organism, usually a plant, to an environmental stimulus is called a tropism. Some common plant stimuli include light, gravity, water, movement of the sun, and touch. The naming of the tropism is associated with the stimulus.

Detailed explanation-3: -A plant’s roots respond to gravity by growing mostly downward. A plant’s stem responds in the opposite way. The stem grows upward, away from the pull of gravity.

Detailed explanation-4: -(a) Roots respond to light, gravity and water stimuli.

Detailed explanation-5: -Plants also have internal stimuli that can cause the organism to respond. For example, if a plant is lacking water inside of its cells, wilting will occur as a response.