Lecture 4: Synaptic Transmission

Question 1

Action potential conduction in axons.

Answer 1

• passive spread of current from the AP opens voltage gated sodium channels in adjacent membrane. AP firing.
• the distance the current can spread depends on the amount of leakage.
• AP refractory period determines the direction of AP potential

Question 2

Describe how the refractory period stops the action potential moving backwards.

Answer 2

1) absolute refractory period

- during repolarisation phase 2nd AP can’t happen no matter how big stimulus is