The Na,K-ATPase

Question

The Na,K-ATPase
A) Makes the resting membrane potential a little more negative
B) Makes no contribution to the resting membrane potential
C) Is electroneutral
D) Is inhibited by tetrodotoxin
E) Both A and C are correct

Accepted Answer

The Na,K-ATPase contributes to the resting membrane potential by pumping 3 Na+ ions out and 2 K+ ions into the cell, making the inside of the cell slightly more negative. It is not electroneutral, and tetrodotoxin inhibits voltage-gated sodium channels, not the Na,K-ATPase.