1. A complex of proteins and pigments in the thylakoid membrane of chloroplasts that captures light energy and converts it into chemical energy during photosynthesis.
Usage: technical; biology

Examples

• Photosystem II is responsible for splitting water molecules and releasing oxygen during photosynthesis.
• Plants use two main photosystems, called Photosystem I and Photosystem II, to harvest light energy.
• The photosystem contains chlorophyll and other pigments that absorb different wavelengths of light.
• Electrons excited by light in the photosystem travel through an electron transport chain.
• Damage to the photosystem can reduce a plant's ability to perform photosynthesis efficiently.