Theoretically, a recognized member of the modern state system possessing formal sovereignty and occupied by a people who see themselves as a single, united nation. Most nations and states aspire to parlance, nation-state is used as a synonym for country or state.
In biology, depolarization is a decrease in the absolute value of a cell's membrane potential. Thus, changes in membrane voltage in which the membrane potential becomes less positive or less negative are both depolarizations.
(3a) the initial depolarization of the outer cell membrane is transmitted along the length of the cell and throughout the cell interior via a T-tubule system. (3b) meanwhile the sodium (Na+) channels are closing and the sodium-potassium ATPase pumps are continuing to operate.