Zusammenfassung der Ressource
Action potential (ms mV)
- Resting potential/ polarised
- ATP pump, 2K+in, 3Na+out
- -60mV potential difference inside membrane compared
to outside membrane means it is polarised
- More permeable to K+ than Na+
- Kinetic E. opens Na+ channels
- Na+ floods in down electrochemical
gradient, converting it to electrical E.
- If it reaches -50mV (threshold
potential) then will go to depolarisation
- (Na+ and K+ gated channels
were both closed before)
- (net - inside, net + outside)
- K+channels open, K+ going out
- Depolarisation
- ATP pump, 2K+in, 3Na+out
- K+channels open, K+ going out
- +40mV potential difference inside membrane compared
to outside membrane means it is depolarised
- (net + inside, net - outside)
- Repolarisation
- ATP pump, 2K+in, 3Na+out
- K+channels open, K+ going out
- K+ gated channels open, K+ flows
out down electrochemical gradient
- More flows out than needed meaning it becomes hyperpolarised
- Hyperpolarisation
- ATP pump, 2K+in, 3Na+out, and
permeability starts to restore balance
- (Not able to register any more pain
until back to resting potential)
- K+channels open,
K+ going out
- K+ gated channels close