David Hackos's Channel Page Ion Channels Ion channels are membrane proteins that allow ions to flow across the cell membrane . The human nervous system has thousands of different kinds of channels all working together - providing the basis for human behaviour and the human mind.
Channels are generally either open or closed.
How often the channel is open is called the open probability . This ionic selectivity of the channel is an extremely important aspect of the channel's functional properties. In fact, channels are generally characterized by their ionic selectivity.