lecture 4 - equilibrium potentials and permeability

nernst equation

calculates equilibrium potential for one specific ion

equilibrium potential

no net flux of a specific ion, when the membrane potential (voltage) with the concentration gradient is equal to the electrical gradient force

permeability

how readily ions can cross a membrane

conductance

measure of the rate of ionic flux

flux

ionic movement across the cell membrane

goldman equation

for estimating membrane potentials, given the permeability of each ion (p=between 0 and 1, 0 being no permeability and 1 being complete)

equilibrium potentials (Na, K, Cl)

Na = +60 mV

K = -90 m

Cl = -65 mV

depolarizing stimulus

pulls membrane towards +, decreases charge (resting = -)