Photosynthesis

• The light dependent stage takes place in the thylakoid membranes of the chloroplasts, while the Calvin cycle occurs in the stroma.
• The products of the light dependent stage are oxygen, NADPH and ATP
• Photosystem is the collection of photosynthetic pigments and electron carriers
• 1.) Chlorophyll a absorbs light energy
• 2.) light energy excites the electron and causes it to move from chlorophyll a
• electron moves down the electron transfer chain, releasing energy as it loses excitation energy as they pass
• chain of carrier are arranged at decreasing energy levels
• energy released is used to pump protons across the thylakoid membrane into the intergranal space down a concentration gradient. This is the proton motive force and activates ATP Synthase to phosphorylate and combine ADP + Pi into ATP.
• Chlorophyll A gets oxidised as it loses an electron and the electron reduces the carriers

  (series of REDOX reactions)
• NADP= nicotine adenine dinucletoide phosphate
• phosphorylation of ADP and the proton motive force is chemiosmosis
• light is a limiting factor for the light dependent reaction
• cyclic phosphorylation
• Photolysis of water produces NADPH, oxygen and protons