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nerve impulse





An electrical signal that travels along the axon of a neuron (nerve cell). Nerve impulses carry information throughout the nervous system. As an impulse passes, sodium and potassium ions flow into and out of the axon's membrane (see sodium-potassium pump), creating a voltage reduction called the action potential. Nerve impulses can travel at up to 150m (500ft) per second.


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   • ANATOMY AND PHYSIOLOGY