Question

Assertion: Light is very important external factor of transpiration.

Answer 1

If you increase light, the plant's stomates open. Stomates are pores in the leaf's epiderm that is used for gas changing and transpiration. They open, more water vapour comes out. More light, more transpiration. More light also means more photosynthesis, wich also uses water, but less than 1% of a plant's water is used in this process.

BE SMART ^_^