The equilibrium potential for potassium ions occurs at approximately
A)-90 mV.
B)-70 mV.
C)+66 mV.
D)0 mV.
E)-55 mV.

Question

Quizplus · Accepted Answer

The equilibrium potential for potassium ions is approximately -90 mV. This means that the inside of the cell is negatively charged with respect to the outside, and potassium ions tend to move out of the cell down their electrochemical gradient until the electrical and chemical forces are balanced. This equilibrium potential is determined by the concentration gradient of potassium ions and the permeability of the cell membrane to these ions.

The Equilibrium Potential for Potassium Ions Occurs at Approximately