Speed of conductance Flashcards
What three factors affect the speed of conductance/an action potential?
- myelination and saltatory conduction
- axon diameter
- temperature
What is an axon?
a long, conductive fibre that carries the nervous impulse along the motor neuron
What forms the myelin sheath?
Schwann cells
What about the Schwann cells makes them insulators?
they are lipids
What is saltatory conduction?
the action potential jumping/moving from node to node
why does the myelin sheath speed up conductance?
as action potentials only have to be generated in a limited number of spaces, not along the whole length of the axon
How does a wider diameter impact the speed of conductance?
will make it faster
Why does a wider diameter speed up conductance?
it means that there is less leakage of ions
Why does a higher temperature increase speed of conductance?
- rate of diffusion increases
-enzymes involved in respiration act faster so more ATP for co-transport
Why would no myelin sheaths lead to slower responses?
- cannot ‘jump’ from node to node
- more depolarisation over a greater length
