AP BIOLOGY

Detailed explanation-1: -Phototropism is the ability of the plant to re-orient the shoot growth towards a direction of light source. Phototropism is important to plants as it enhances the ability of plants to optimize their photosynthetic capacity. As discussed above, phototropic response is exclusively controlled by phots.

Detailed explanation-2: -Phototropism, or the differential cell elongation exhibited by a plant organ in response to directional blue light, provides the plant with a means to optimize photosynthetic light capture in the aerial portion and water and nutrient acquisition in the roots.

Detailed explanation-3: -The bending of growing plants towards the light is called phototropism. By orienting their leaves and stems towards light plants receive the maximum energy for photosynthesis. This process is mediated by a plant hormone called Auxin.

Detailed explanation-4: -A plants response to light has been well documented and studied. It is known to be due to differential elongation of the cells in the plant stem. Stem cells away from the light elongate in response to special auxins (growth hormones) causing the plant stem to bend towards the light.

Detailed explanation-5: -Phototropism is the movement of plant parts in response to light. Thus, the stimulus for phototropism is “Light”.