Left panel. The activation kinetics of macroscopic delayed rectifier K currents reflects the (relatively slow) movement of the voltage sensors.
Right panel. The binary behavior of the gate can be directly observed using single channel recordings. The transition between the “open” and “closed” state is too fast to be resolved experimentally.
Note that after the macroscopic current has reach a steady state, individual channels continue to open and close (with a constant probability): “activation kinetics” and “gating kinetics” are distinguishable and therefore have a distinct structural basis.