Why does the rotor spin faster with a strong proton gradient?

The F0 rotor is turned by protons flowing down their electrochemical gradient through its c-ring. A strong gradient means a large excess of H+ ions on the intermembrane side, so more protons flow per second and the rotor spins faster; a weak or absent gradient slows or stalls it.

Why does the F1 head stay still while the rotor spins?

In the real enzyme the F1 head is held in place by an external stator arm, so only the rotor and its gamma stalk turn inside it. Every 120 degrees of that internal rotation forces one of F1's three catalytic sites through a shape change that releases a newly made ATP.

What does the ADP + Pi availability slider model?

Even a fast-spinning rotor only produces ATP if ADP and inorganic phosphate are available at the catalytic site. Lowering this slider makes some 120-degree steps mechanically complete without yielding an ATP molecule, modeling substrate-limited synthesis.

Home▸Molecular Biology▸ATP Synthase Chemiosmosis (2D)

ATP Synthase Chemiosmosis (2D)

A flat side-view schematic of the F0/F1 rotary motor: a proton gradient across the membrane spins the F0 rotor, and every 120-degree click of the stalk drives the fixed F1 head to condense ADP + Pi into ATP.

Molecular Biology2DModerate60 FPS📱 Mobile-adapted⇄ 3D version

This 2D companion drives the same chemiosmotic mechanism as the 3D scene through a plain side-view canvas: choosing a proton-gradient strength sets how many revolutions per second the F0 rotor turns, and each completed 120° step of the stalk lights one of the F1 head's three fixed catalytic sites and, if enough ADP and phosphate are available, releases a new ATP particle — so the link between proton flow, rotor speed and ATP output is visible as three synced numbers rather than implied.

⚙ Under the hood

2D chemiosmosis lab: proton-gradient presets set F0 rotor rev/s, a fixed 120-degree step counter drives catalysis on the F1 head, and a substrate-availability slider models ADP+Pi-limited ATP yield.

biologybiochemistrymitochondriaatp synthasechemiosmosisbioenergetics

2D · HTML5 Canvas 2D · 60 FPS target · runs fully client-side, no install