Explain the reasons of following

Explain the reasons of following.
(i) Photosynthesis can occur in absence of light.
(ii) Even non-green leaves can make the food.
(iii) Photosynthesis can occurs under water.

(i) Photosynthesis can occur in absence of sunlight but only for a certain period. The sunlight originally supplies the energy for conversion of ${{CO}_{2}}$ to carbohydrate.
(ii) Yes, the chlorophyll is the most prominent plant pigment but not always. Some other accessory pigments such as xanthophylls and carotenoids can also perform photosynthesis separately.
(iii) Photosynthesis can occur under water only when the water is clear and shallow. Some
Alga (Rhodophyta) can synthesize food at deep water layers as they absorb more blue light region efficiently.