Answer:
Light and dark reaction are the two different phases of photosynthesis.
Photosynthesis is a process of formation of food in green plants and algae using carbon dioxide and water in the presence of sunlight.
Light reaction ( light dependent phase) occurs in the thylakoid membrane of chloroplast and is the first phase of photosynthesis.
During this phase, chlorophyll ( a green pigment in the chloroplast) absorbs energy from sunlight and converts it into chemical energy in the form of ATP and NADPH. Photolysis of water takes place in this reaction that produces oxygen as a waste product in the surrounding.
Dark reaction occurs in the stroma. During the dark reaction ( light independent phase) , this chemical energy is used in the formation of carbohydrates ( glucose) as ATP provides energy for this process wheres NADPH is a reducing agent, which gives electrons that are need for CO2 fixation so as to form glucose molecule.
