If you observe the activity at the cell membrane as the action potential passes, first you will see ________ the cell, then you will see ________ the cell
a. NA+ enter; K+ leave
b. NA+ leave; K+ enter
c. NA+ leave; NA+ enter
d. K+ enter; NA+ leave
e. K+ leave; NA+ enter
A; A local drop in the membrane potential triggers the gates of the sodium channels to open, initiating the action potential. This allows entry of sodium ions into the cell. Potassium then leaves through the potassium channel.
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