Biology · Coordination and Control

An action potential is a rapid and temporary change in the membrane potential of a neuron or muscle cell that allows for the transmission of electrical signals. It occurs when a stimulus depolarizes the membrane to a threshold level, typically around -55 mV.

The function of K⁺ leakage is to help maintain the resting membrane potential by allowing a small, passive movement of potassium ions out of the cell.

Resting membrane potential is the electrical potential difference across the plasma membrane of a neuron or muscle cell when it is not actively transmitting signals. Typically around -70 mV, this potential is primarily established by the distribution of ions, particularly sodium (Na⁺), potassium (K⁺), chloride (Cl^-), and various anions.

An action potential is a rapid and temporary change in the membrane potential of a neuron or muscle cell that allows for the transmission of electrical signals. It occurs when a stimulus depolarizes the membrane to a threshold level, typically around -55 mV.

Repolarization is the phase of the action potential in neurons and muscle cells where the membrane potential returns to its resting state after depolarization. This process follows the peak of the action potential, where the inside of the cell becomes positively charged due to the influx of sodium ions (Na⁺).

Sub-threshold potential refers to the membrane potential that occurs in a neuron when a stimulus is not strong enough to reach the threshold needed to trigger an action potential. This potential represents a graded response, where the depolarization of the neuron's membrane occurs, but it does not reach the critical level required for the voltage-gated sodium channels to open.