PSYC 2012 Lecture Notes - Lecture 6: Voltage-Gated Potassium Channel, Resting Potential, Membrane Potential
Document Summary
Pump pushes 3 na+ for every 2 k+ it pushes in. Slightly more positively charged potassium leaving the cell. Resting membrane potential - difference in charge between inside and outside of cell at rest. Adding more and more positive charge to the inside of the cell results in larger and larger depolarizations. The action potential: a rapid, transient, all-or-none change in membrane potential. Cell depolarizes explosively and then very rapidly repolarizes. Once we cross the threshold, we always can an action potential of the same size. Ex. flushing a toilet - as long as you push it hard enough it will create the same size flush no matter how hard you push it - (cid:373)ore does(cid:374)"t (cid:373)ake it (cid:271)igger. We always get the same size action potential. Depolarization: inside of cell rapidly becomes less negative/more positive. Repolarization: inside of cell rapidly becomes less positive/more negative and returns toward negative resting membrane potential.
