Describe how an action potential is transmitted across a synapse

The arrival of an action potential at the end of the presynaptic neurone causes Ca2+ protein channels to open Ca2+ ions diffuse into the synaptic knob by facilitated diffusionCa2+ ions cause synaptic vesicles to fuse with the presynaptic membrane - releasing ACh inot the synaptic cleftACh molecules diffuse across the synaptic cleft and bind to Na+ ion channels on the presynaptic neuroneThis opens the Na+ ion channels, casuing Na+ to diffuse rapidly into the post synaptic neuroneThe influx of Na+ depolarises the post synaptic neurone - generating a new action potentialAcetylcholinesterase hydrolyses ACh into acetyl and choline. These diffuse back across into the presynaptic cleftATP released by mitochondria is used to recobine the choline and acetyl in the presynaptic cleft. This is then stored in vesicles for future use

GR
Answered by George R. Biology tutor

2386 Views

See similar Biology A Level tutors

Related Biology A Level answers

All answers ▸

How does increasing temperature affect the rate of a reaction in the presence of an enzyme.


Describe the different levels of protein structure during the production of a protein


What is speciation?


Describe the sequence of events that lead to the generation of an action potential


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning