Transmission of Action Potentials

Question 1

How do action potentials occur in non-myelinated axons?

Answer 1

Action potentials are transmitted in non-myelinated axons
because when depolarisation happens, it causes voltage-gated sodium channels to open further down the axon. By
the time the depolarisation has spread, part of the axon is repolarising

Question 2

How do action potentials occur in myelinated axons?

Answer 2

action potentials only occur at the nodes

of Ranvier, with charge diffusing along the cell where myelin is present (saltatory conduction)

Question 3

Name 3 factors affecting transmission speed…

Answer 3

Myelination
Axon Diameter
Temperature

Question 4

Transmission is faster when…

Answer 4

neurones are myelinated and have a wider axon diameter and when it is warmer. (Up until denaturing)

Question 5

Transmission is slower when…

Answer 5

neurones are Unmyelinated and have a narrower axon diameter and when it is colder.