What is an action potential?

An action potential refers to a brief electrical charge that travels along the axon of a neuron. This phenomenon occurs when a neuron is sufficiently stimulated, causing the membrane potential to change rapidly. During an action potential, voltage-gated sodium channels open, resulting in an influx of sodium ions that depolarizes the membrane. This depolarization is followed by the opening of potassium channels, which allows potassium to exit the cell, repolarizing the membrane back to its resting state.

The significance of an action potential lies in its role in transmitting information within the nervous system. It is the fundamental mechanism by which signals are conveyed along axons to communicate with other neurons, muscle cells, or glands. The rapid movement of the action potential allows for fast and efficient signal transmission across long distances within the body.

Other options describe different aspects of neuronal function but do not accurately define an action potential. For instance, neurotransmitters are chemical messengers released at synapses, and while they play a crucial role in neuronal communication, they are distinct from the electrical events of action potentials. Similarly, while there are signals involved in sensory neurons, an action potential is not limited to those signals and encompasses all forms of neuronal communication. Finally, internal communication methods for the brain can