The Graph Shows the Changing Electrical Charge of a Neuron

Multiple Choice

The graph shows the changing electrical charge of a neuron when it activates. Pick the alternative that correctly labels the different phases depicted in the graph.

A) 1 = action potential, 2 = stimulus threshold, 3 = refractory period, 4 = resting potential
B) 1 = ions cross membrane, 2 = action potential, 3 = stimulus threshold, 4 = depolarization
C) 1 = depolarization, 2 = action potential, 3 = stimulus threshold, 4 = repolarization
D) 1 = resting potential, 2 = ions cross membrane, 3 = action potential, 4 = refractory period