Question

effects of light and dark on the metabolic process of plants and animals?

Answer 1

Presence or absence of light directly affects plants. This is because light is the primary condition for photosynthesis – production of organic compounds from non-organic ones.

Presence of light is also important for animals. They develop adaptive reactions for this and have different regimes of activity during day and night. Light is also important for the ability of human to synthesize vitamin D in their skin.