Lecture5(11) - Electrochemical equilibrium Nernst equation...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
Electrochemical equilibrium
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
Nernst equation The value of such an equilibrium potential depends on the ionic species, and it is given by the Nernst equation where are concentrations of the ions outside and inside the cell, respectively, R is the universal gas constant (8,315 mJ/(K Mol)), T is temperature in degrees Kelvin (K = 273.16 ), F is Faraday’s constant (96,480 Coulombs/Mol), z is the valence of the ion (z = 1 for Na + and K + , z = -1 for Cl - , and z = 2 for Ca 2+ ). For T=293 K (20C) and z=1: ( / )ln( / ) ion out in E RT zF C C = 58log( / ) ion out in E C C At the equilibrium potential, the concentration gradient and the electric potential gradient exert equal and opposite forces that counterbalance each other, and the net cross-membrane current is zero. out in C and C
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 4
Driving force Current through the membrane is equal to zero when V m =E k (V m -E k ) is driving force Channel conductance Channel current
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
GHK equation [ ] [ ] 1 / 96,480 / v in out v m C C e I PzvF e v zV F RT
Background image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 01/31/2011 for the course CBNS 120 taught by Professor Adams during the Winter '10 term at UC Riverside.

Page1 / 27

Lecture5(11) - Electrochemical equilibrium Nernst equation...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online