If the Extracellular Concentration of Sodium Ions is Artificially Decreased

Question

If the extracellular concentration of sodium ions is artificially decreased for a neuron, …
A) both the resting potential and the peak of the action potential rise significantly.
B) the resting potential increases but the action potential peak does not.
C) the resting potential hardly changes but the action potential peak is raised.
D) the resting potential decreases but the action potential peak is raised.
E) the resting potential hardly changes but the action potential peak is lowered.

Accepted Answer

The resting membrane potential mostly depends on the electrochemical potential of the potassium ion, whereas the action potential is more dependent on the sodium ion, and its peak is expected to be lowered if the extracellular sodium concentration is decreased.