Question

How does shoots respond by bending towards light and roots respond by bending away from it help the plant?

Answer 1

Answer:

+shoots respond positively (positive phototrophism) by bending towards light

+roots respond negatively showing negative phototrophism

Answer 2

Plants have a hormone called auxin that stimulates cell elongation and is accumulated at the shoot tip on the opposite side of the side on which sunlight is falling, this results in the shoot bending towards the light source for increased photosynthesis. the exact opposite happens at the root tips. This is a type of tropic movement (growth related movement) in which the stimuli is light and hence known as phototropism.

As shoots grow towards light , they are positively phototropic and as roots grow away from light they are negatively phototropic.