The pigments found in chloroplasts include chlorophyl a, chlorophyll b, carotenoids, xanthophylls and phycobilins. Chlorophyll a is a primary photosynthetic pigment, while the rest are considered accessory pigments.
Photosynthesis is carried out by green plants, algae and cyanobacteria. This process involves the transformation of solar energy into chemical energy that is stored in glucose, which is the main biological fuel of most organisms. Photosynthesis utilizes water and carbon dioxide from the air to produce glucose and oxygen. Specialized structures, called "chloroplasts," are the sites of photosynthetic activity. The chloroplasts consist of an internal and external membrane, intermembrane space, stroma and grana, which are layers of the thylakoids where the light reactions of photosynthesis occur.
Pigments are chemical substances that absorb or radiate specific wavelengths of visible light. In photosynthetic organisms, these natural compounds are used in harvesting the energy from the sun. Chlorophyll and the accessory pigments are bundled within the thylakoid membranes.
Chlorophyll a is the primary pigment that converts the captured solar energy into chemical energy. It absorbs wavelengths of visible light that correspond to red and blue and reflect the green light, which is the dominant color of the leaves of photosynthetic plants. The accessory pigments help absorb the wavelengths of light not absorbed by chlorophyll a. Another type of pigment, called anthocyanins, is non-photosynthetic and is not located within the chloroplasts.