1. Resting Membrane Potential
Whitney Theis
March 31, 2006

2. Charge of a Cell Normally a cell is more negative on the inside
On average -70mV
The negative charge forms a thin layer along the inside of the membrane

3. Major Players in Resting Potential
Na+, K+, and Cl-
The resting potential due to the efflux of K+ out of the cell
Leaky channels
Relative concentrations

4. Development of Resting Potential
Cell thrown out of resting potential when impulse occurs across membrane
When this happens the ATPase pump offsets the action
There are K and Na channels that are always open
K flows out faster than Na

5. ATPase Pump Allows two potassium ions in and three sodium ions out
This pump offsets the slow leak of Na+ into the cell
The leaky potassium channels are not offset by the pump
Thus membrane potential due to eflux of potassium