(a) Name the hormone which is secreted when growing plants detect light. Mention its site of secretion in a plant.
(b) Explain why do plants appear to bend towards light?

Explanation

(a) Auxin hormone is secreted in the growing plant which detects light.
`*` It is present in the tip of the growing stem.
(b) Plants appear to bend towards light. As more auxin is produced on the shaded side than on the lighted side of the stem, so stem grows faster on the shaded side than on the lighted side.