Resting membrane Nat is more concentrated Potential outside than inside and therefore tends to flow into the cell down its concentration Net negative Net positive Charge Charge gradient Electric Force Nat Nat Nat is driven into the cell by the electrical potential Chemical force Inside difference across the Outside membrane But what about sodium? Electrostatic and Chemical forces act together on Nat ions to drive them into the cell The Nat channel close during the resting state16 Resting Membrane Potential • But what about sodium? • Electrostatic and Chemical forces act together on Na+ ions to drive them into the cell • The Na+ channel close during the resting state Na+ is more concentrated outside than inside and therefore tends to flow into the cell down its concentration gradient Na+ is driven into the cell by the electrical potential difference across the membrane