Depolarisation,Repolarisation, Resting Potential, Action Potential & Propagation Flashcards
What is depolarisation the start of
Action potential
What causes the sodium channel to open on the axon
A local current
What happens when the sodium channels are open in an axon
Sodium comes into the axon
What happens to the volts when the sodium gets into the axon
It increases up to +40
When the axon reaches its full potential volts, what happens
Potassium (K) then begins to leave
What are the volts of the axon at resting potential
-70
What happens to the volts when potassium begins to leave
It increases until it’s below -70 and then it goes back up to -70
What is the refractory period
Sodium channels can’t open as volts are below -70
What is propagation
It’s like the Mexican wave down axons to create action potential
What does myelination do to propagation speed
Makes it faster
What fibre is too slow for propagation and why
fibre C and because it isn’t myelinated
What starts off action potential
Depolarisation
What is depolarisation
It is when sodium ions rush through into the neutron
What’s it called when sodium ions rush through into the neutron
Depolarisation
What effect does a local current have on an axon during action potential
Sodium channels open
