Agonist–Antagonist Dose-Response Simulator

This simulator renders a field of drug receptors on a cell membrane in 3D and drives their occupancy from the real Emax/Hill equation pharmacologists use to characterise receptor-targeted drugs. Titrate the agonist concentration on a log scale and watch receptors light up green as they bind, while a live dose-response curve traces the sigmoid response beneath. Switch on a competitive antagonist and the curve shifts rightward — more agonist is needed for the same effect, but the ceiling stays the same, because the antagonist can be out-competed. Switch to a noncompetitive antagonist instead and the ceiling itself drops, because those receptors are removed from the functional pool no matter how much agonist is added. Live readouts track fractional occupancy, response, and the apparent EC50/Emax exactly as a lab assay would report them.