Question

Why does photosynthesis occur during the day time only????

Answer 1

Photosynthesis doesn't occur during day time only. The whole set of reactions involved in photosynthesis is divided into light dependent reactions which take place during day time and light independent reactions which take place during night.

Light dependent reactions takes place in the grana of chloroplast as they contain light sensitive photosystems commonly called as chlorophyll.

Light independent reactions takes place in the stroma of chloroplast as they lack chlorophyll.