BIOMOLECULES AND ENZYMES

Detailed explanation-1: -Promotes Tropism: Auxin induces phototropism, gravitropism and thigmotropism, i.e. movement in response to light, gravity and touch, respectively.

Detailed explanation-2: -Answer: Auxin is responsible for apical dominance and phototropism. Apical dominance means that a plant has the tendency to grow quickly up the central shaft without properly filling in the plant with smaller limbs and leaves.

Detailed explanation-3: -Phototropic movement in plants in response to light is stimulated by the concentration of auxin, the plant growth hormone.

Detailed explanation-4: -Tropisms are controlled by hormones called auxins. Tropisms react to varying conditions of light, gravity and water. There are both positive and negative tropisms.

Detailed explanation-5: -Both phototropism and geotropism are controlled by the distribution of auxin within the plant cells: In geotropism, auxin will accumulate on the lower side of the plant in response to the force of gravity. In phototropism, light receptors (phototropins) trigger the redistribution of auxin to the dark side of the plant.