AP BIOLOGY

Detailed explanation-1: -Hint: Plant responds to three main stimuli: water, gravity, and light. Response or orientation of plant shoot and roots towards these stimuli is known as ‘Tropism ’.

Detailed explanation-2: -The movement or the growth of a plant in relation to the stimulus of water is called hydrotropic movement and the equivalent response to the stimulus of water is called hydrotropism. In this type of movement, roots show positive hydrotropic response, as they move and grow towards the water. Q.

Detailed explanation-3: -Some of the common factors that affect plant growth include light, gravity, water, and touch. Plant tropisms vary from other stimulus-generated movements, such as nastic motions, in that the reaction direction is determined by the stimulus.

Detailed explanation-4: -Types of tropisms include gravitropism (gravity), phototropism (light), and thigmotropism (touch). Plant roots always grow downward because specialized cells in root caps detect and respond to gravity. This is an example of a tropism. A tropism is a turning toward or away from a stimulus in the environment.

Detailed explanation-5: -Tropisms are directional growth responses that occur in response to directional stimuli. Phototropism occurs when plants direct their growth towards or away from light.