peripheral nervous system

Question 1

what are the 3 different types of synapses

Answer 1

axoaxonic synapse
synap;she’s made by one neurone onto th synapse of another neurone

axodendritic synapse
synapses that one neurone makes onto the dendrite of another neurone

axosomatic synapse
- synapses that are made onto the soma or cell body of a neurone

Question 2

what is the process of synaptic transmission

Answer 2

1. action potential invades the pre synaptic terminal
2. depolarisation opens Ca2+ channels
3. Ca2+ rise triggers vesicles
4. transmitters diffuse across synaptic cleft to post synaptic receptors
5. nicotinic ach receptors activation depolarises the membrane
6. post synaptic potential triggers an action potential
7. signalling is turned of by transmitter removal ( acetylcholineestrase)

Question 3

how do neutroansmitters become inactive

Answer 3

• 3 processes
• metabolised extracellularly - the neutrotransmitter is broken down
• it is taken up post or presynaptically - where it may be metabolised intracellularly
• diffuses away from synaptic cleft - so no effect on the post synaptic receptors

Question 4

what are the neurotransmitter classes

Answer 4

• acetylcholine
• monoamines ( noradrenaline + dopamine)
• amino acids ( glutamate + GABA)
• neuropeptides ( short peptides modulatory transmitters)