antenna complex

molecules to oxygen, protons and electrons.The light-harvesting (or antenna) complex of plants is an array of protein and chlorophyll molecules embedded in the thylakoid membrane which transfer light energy to one chlorophyll a molecule at the reaction center of a photosystem.
The antenna pigments are predominantly chlorophyll a, chlorophyll b and carotenoids. Their absorption spectra are non-overlapping in order to broaden the range of light that can be absorbed in photosynthesis. The carotenoids have another role as an antioxidant to prevent photo-oxidative damage of chlorophyll molecules. Each antenna complex has between 250 and 400 pigment molecules and the energy they absorb is shuttled by resonance energy transfer to a specialized chlorophyll-protein complex known as the reaction center of each photosystem. The reaction center initiates a complex series of chemical reactions that capture energy in the form of chemical bonds.
For photosystem II, when either of the two chorophyll a molecules at the reaction center absorb energy, an electron is excited and transferred to an electron acceptor molecule, phaeophytin, leaving the chlorophyll a in an oxidized state. The oxidised chlorophyll a replaces the electrons by photolysis that involves the reduction of water