You are one electron. The map on the right is a cross-section of the thylakoid membrane: stroma above, lipid bilayer through the middle, lumen below.
Each level zooms in on one slice of it. Your route runs from water at photosystem II all the way to NADP⁺ in the stroma.
ControlsTap, click, or press Space to jump. You run on your own whenever you have energy.
EnergyPhotons add energy. Jumps and proton pumping spend it. Energy carries over between levels.
Four levels1 · break out of water and climb out of PS II. 2 · down the chain to PS I. 3 · climb out of PS I. 4 · up into the stroma to NADP⁺.
Watch the protonsEvery H⁺ you push into the lumen builds the gradient that ATP synthase uses in the last level.