action potential: Quick Facts

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Facts

Also Known As	propagated potential

Photos

Diagram comparing action potential conduction in myelinated and unmyelinated axons, showing a neuron with labeled cell body, myelin sheath, nodes of Ranvier, and the flow of electrical signals along each type of axon.

ion permeance and action potential

graph depicting the five phases of the action potential of the heart muscle

Diagram showing the chemical transmission of nerve impulses at a synapse, with labeled steps illustrating neurotransmitter release from the presynaptic terminal, movement across the synaptic cleft, binding to postsynaptic channel receptors, and resulting signal propagation in the nervous system.

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Topics

absolute refractory period sodium inactivation relative refractory period conduction all-or-none law saltatory conduction conduction velocity synapse threshold potential neuromuscular junction postsynaptic potential resting potential end-plate potential summation

Dig Deeper: More Articles That Discuss This Topic

nervous system: Action potential

Key People

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Ragnar Arthur Granit

Swedish physiologist