The cell membrane contains different types of ion channels that selectively allow the permeability of ions. The ion channels can be either voltage sensitive or ligand sensitive.
Examples of different ion channels include, voltage sensitive sodium channels, potassium channels, chloride channels, calcium channels and many other.
The different types of ion channels allow the nerve cell to perform a wide range of neural events. For example, the sodium and potassium channels are mainly involved in maintaining the membrane potentials, generating graded potentials and action potentials.