Final answer:
The light dependent reaction takes place in the thylakoid membranes of the chloroplasts. Thylakoids are disc-shaped structures that contain chlorophyll and other pigments. They are responsible for capturing light energy and using it to produce ATP and NADPH.
Step-by-step explanation:
Light Dependent Reaction and Thylakoids in Photosynthesis
The light dependent reactions of photosynthesis occur in the thylakoid membranes of the chloroplasts. Thylakoids are disc-shaped structures that contain chlorophyll and other pigments. They are interconnected to form stacks called grana.
During the light dependent reactions, sunlight is absorbed by the pigment molecules in the photosystems of the thylakoids. This energy is used to generate ATP (adenosine triphosphate) and NADPH (nicotinamide adenine dinucleotide phosphate) which are energy-rich molecules used in the subsequent reactions of photosynthesis.
The reactants in the light dependent reactions are water and light energy, while the products are oxygen (released as a byproduct) and energy-rich molecules (ATP and NADPH) that are used in the Calvin cycle, the light-independent reactions of photosynthesis.