Action Potential Flashcards
What are 2 ways we have discovered to speed up conduction velocity?
Large axons
Myelination
What do you can it when the electric current find it’s harder to flow down a small axon?
Axial resistance
Are a a squid sodium channels packed tightly or spaced along the membrane?
Spaced out
Why can the AP of sodium channels along a wide axon spread further?
They move possibly, quickly and further
What are the myelinating cells of the PNS?
Schwann cells
Aka oligodendrocytes (CNS)
What are these gaps called?
Nodes of ranvier
How does myelination increase AP movement?
Increases membrane resistance
Reduces membrane capacitance (you want)
Therefore, less current is wasted
The AP can spread even further
How would you describe the effects of myelination on AP?
Saltatory conduction
Node to node
What are demyelinatung disease?
Multiple sclerosis (MS) (CNS)
Guillain-Barré syndrome (PNS)
How would you describe the ability of an axon to conduct AP?
Its velocity
Where is the compound AP measured from?
Extracellular recording from a nerve
Generates a compound AP
What does the compound AP tell us?
Gives a classification of axons based on their conduction velocity
What does the compound AP correlate to, anatomy or function?
Anatomy
What are the fast conducting axons and what is the slowest conducting axons?
Describe A-C
