10. Synpapses

Question 1

outline the process of an action potential arriving at a cholinergic synapse

Answer 1

1. action potential arrives at the presynaptic neurone, causing vovltage gatage calcium channels to open
2. the influx of calcium causes vesicles containign AcH to fuse with the membrane and release neurotransmitters via exocytosis
3. AcH diffuses across the synaptic gap, they attach to a receptor binding site which causes the laegin sodium channels to open
4. this causes an influx of sodium ions in the postsynaptic neurone if threshold is reached an action potential will be fired
5. AcH is then hydrolysed by Acetylesterase, to make acytel and choline, so it can be reabsorbed into the presynaptic neurone
6. ATP then synthesises these products to produce AcH again

Question 2

what is the difference between cholineric and adregenic synapse?

Answer 2

cholinergic is between two neurones, and adregenic is between the presynapse and the effector