Action Potential

An action potential is a momentary electrical event occurring through the membrane of a nerve cell fiber in response to a stimulus, forming a nerve impulse.

An action potential is transmitted along a nerve fiber as a wave of changing electrical charge. This wave travels at a speed that ranges from about five feet (1.5 meters) per second to about 350 feet (107 meters) per second, depending on several factors, including properties of the nerve fiber involved.

See also Nerve ; Neural transmission: excitatory and inhibitory synapses; Neuron ; Neurotransmitter .


An atom or molecule with a net electric charge due to the loss or gain of one or more electrons.



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