DENDROLOGY

Detailed explanation-1: -Answer and Explanation: Phototropism is the ability of plants to turn either towards or away from light sources providing the necessary light for photosynthesis. Geotropism is a plants ability to orient themselves in space for growth.

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: -Definition. Phototropism refers to the orientation of a plant or other organism in response to light while geotropism refers to the growth of the parts of plants in response to the force of gravity. Thus, this is the main difference between phototropism and geotropism.

Detailed explanation-4: -(a) (i) The bending of shoots or other plant parts in response to light is known as phototropism. (ii) The bending or growth of roots towards gravity is known as geotropism.