Classify the given items with the appropriate group: Occurs when voltage-gated sodium channels have returned t0 resting state Occurs about Ims after an action potential Voltage-gated sodium channels are opened then closed in the inactivated state Ensures that the action potentia moves down the axon in only one direction No amount of stimulus will Neuron is hyperpolarized initiate a second action potential Relative Refractory Period Absolute Refractive Period