The membrane potential of cardiac contractile cells at rest is about ____ mV.
A)-110
B)-90
C)-70
D)-50
E)-30

Question

Quizplus · Accepted Answer

The resting membrane potential of cardiac contractile cells is around -90 mV. This is due to the presence of a high concentration of potassium ions within the cell, and a low concentration of sodium ions. This creates an electrochemical gradient that favors the movement of potassium ions out of the cell, making the interior of the cell negatively charged compared to the extracellular fluid.

The Membrane Potential of Cardiac Contractile Cells at Rest Is