PHGY 209 Lecture Notes - Lecture 25: Resting Potential, Nernst Equation, Atp Hydrolysis

• School: McGill University
• Department: Physiology
• Course: PHGY 209
• Professor: John White

Document Summary

You calculate the nernst equation by plugging in the [] of k on the inside and on the outside, and that will tell you where the ions will be at equilibrium. But you can do this for other ions if the membrane was only permeable to that ion! K wants the membrane to go to -90 etc. The resting membrane potential is a bit more positive than ek because there is a small inward leak of na which pushes the membrane slightly towards ena. Even though it has high permeability to k, some na can leak in which pushes the membrane a little more positive. This makes it sit stably: this membrane potential is close to the ek and far for na. the membrane is really permeable to k and a little for na. Atp goes to adp to drive this process. The pumps are responsible for creating and sustaining the potential.