The chlorophyll has been oxidised as it has lost electrons
The electron carrier has been reduced as it has gained electrons
The electrons are passed along a chain of electron carriers in a series of redox reactions in the thylakoid membranes with each carrier at a slightly lower energy level than the one before
Some of the energy released is used to add an inorganic phosphate to an ADP to make ATP. This happens due to the chemiosmotic theory
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The chemiosmotic theory
Each thylakoid pumps protons/H+ ions from the stroma using carrier proteins called proton pumps into the thylakoid space
The energy to do this comes from the electrons released during photolysis
The protons produced from photolysis also increase the proton concentration inside the thylakoid space
This maintains the proton concentration gradient being higher inside the thylakoid space
These protons can only pass into the stroma through ATP synthase channels as the rest of the membrane is impermeable to protons
This changes the shape of the enzyme ATP synthase which catalyses the reaction creating ATP from ADP and an inorganic phosphate
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Photolysis of water
The electrons lost during photoionisation are replaced by electrons released from photolysis
The protons released are passed out of the thylakoid space through the ATP synthase channels and are taken up by an electron carrier called NADP
This reduces the NADP
The reduced NADP is the main product from the light-dependent stage of photosynthesis
This enters the light-independent stage of photosynthesis along with the electrons from the chlorophyll
Reduced NADP is a further potential source of energy
Oxygen produced from photolysis is either used for respiration or diffuses out through the stomata
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