Photosynthesis — light reactions and the Calvin cycle
Both halves on one canvas with the stoichiometry attached: water split at the oxygen-evolving complex to feed P680, electrons through plastoquinone and cytochrome b₆f pumping protons into a lumen at pH 4.5, ATP synthase at 4 H⁺ per ATP, P700 reducing NADP⁺, and the Calvin cycle spending 3 ATP and 2 NADPH per CO₂ fixed.
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