What is the role of the cell membrane?
© to control the functions of the cell
to provide a firm structure for the cell
to control what enters and leaves the cell
O
to

To control what enters and leaves cell

Explanation:

the answer that best describes the relative refractory period in the neuron is the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

the refractory period is the time during which another stimulus given to the neuron will not lead to a second potential. thus, because na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials.  

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