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• Photolysis: Light energy is absorbed and used to split water into hydrogen ions, electrons and oxygen. Oxygen is released as a waste. Hydrogen ions remain in the thylakoid space and contribute the electrochemical gradient across the thylakoid membrane. The electrons are taken up by photosystem II for use in the light dependent reactions.
• Photophosphorylation is the synthesis of ATP from ADP and inorganic phosphate using light energy in photosynthesis. This occurs in the chloroplasts.
• Photosystem II: Consists of pigment complex and electron acceptor molecules. Replacement electrons come from the photolysis of water
• Photosystem I: Consists of pigment complex and electron acceptor molecules. Replacement electrons come from the PS II passed on by the ETC.
• NADP reductase: which uses the hydrogen ions and electrons from photosystem I to reduce NADP+ .
• ATP synthase complex: consists of a hydrogen ion channel and the enzyme ATP synthase.
• Electron transport chain: Consists of a series of proteins which act as electron carriers transporting electron from PS II to PS I. Some of these proteins acts as pumps and pump hydrogen ions from the stroma into the thylakoid space