the inside of the neuron is 70 mV less than the outside. At rest, there are relatively more sodium ions outside the neuron and more potassium ions inside that neuron. When a nerve impulse stimulates ion channels to open, positive ions flow into the cell and cause depolarization, which leads to muscle cell contraction.

What happens when a neuron depolarize?

Depolarization occurs when a stimulus reaches a resting neuron. During the depolarization phase, the gated sodium ion channels on the neuron's membrane suddenly open and allow sodium ions (Na+) present outside the membrane to rush into the cell. ... As a result, the inner portion of the nerve cell reaches +40 mV.

What is depolarization of a neuron?

Depolarization is a positive change from the resting potential achieved by increased permeability to an ion with a Nernst potential above the RBP.