Explain how nerve transmission occurs at the synapse.

As an action potential arrives at the presynaptic knob, the membrane is depolarised. This causes calcium channels in the membrane to open and calcium ions to flood in. This influx of calcium causes vesicles that contain neurotransmitters (e.g. acetylcholine) to fuse with the presynaptic membrane, emptying their contents into the synaptic cleft. The neurotransmitters then bind with complementary receptors on the post-synaptic membrane causing sodium ion channels to open and sodium ions move into the post-synaptic membrane. If the generator potential created by this influx of sodium ions reaches the threshold, an action potential begins along the next neuron.

AH
Answered by Abigail H. Biology tutor

2312 Views

See similar Biology A Level tutors

Related Biology A Level answers

All answers ▸

Briefly describe the mechanism of muscle contraction.


The actual size of a microrganism is 3.6 micrometres and the image size is 9 cm, what is the magnification of the diagram?


What is the tertiary structure of a protein?


What is Darwin’s theory of Evolution by Natural Selection? What is the evidence?


We're here to help

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

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences