How do plants capture light energy for use in photosynthesis?

Photosynthesis is defined as the synthesis of complex carbohydrates from simple substances like carbon dioxide and water in presence of light.

Light provides the energy required for the synthesis of carbohydrates during photosynthesis. Only green parts of the plants, particularly leaves, entrap sunlight as green parts contain a pigment, called chlorophyll.

Chlorophyll is capable of entrapping sunlight. Thus non-green plants, which lack chlorophyll, can't entrap sunlight.

Solar energy is required for the initial step of photosynthesis, called light reaction in which solar energy is converted into chemical energy in form of ATP molecules.

This synthesis of ATP molecules utilizing solar energy is termed as photo-phosphorylation.

ATP molecules release energy during dark reaction of photosynthesis and get converted into ADP molecules. These ADP molecules are subsequently converted into ATP molecules utilizing solar energy during light reaction.

Thus dark reaction of photosynthesis, in which synthesis of carbohydrate occurs from carbon dioxide and water, is indirectly dependent upon light.

Through pigments called chlorophyll, which are found in their chloroplasts, plants are able to absorb light energy. This energy is then used to power the process of photosynthesis, which turns carbon dioxide and water into glucose and oxygen. Chlorophyll is particularly effective at absorbing red and blue wavelengths of light while reflecting green light.