The Process Of Synaptic Trasnmision Flashcards
What is synaptic transmission?
The process by which neighbouring neurons communicate with each other by sending chemical messages across the synapse
What are neurotransmitters?
Brain chemicals released from synaptic vesicles that relay signals across the synapse from one neuron to another another - they are either excitatory or inhibitory
What is the first step in ST?
Information is passed down the axon of the neuron as an electrical impulse - know as action potential
What is the second step in ST?
At the end of the axon terminal are the synaptic vesicles which contain neurotransmitters
What is the third step in ST?
Once the action potential reaches the end of the axon it needs to be transferred to another neuron or tissue by crossing the synaptic gap
What is the fourth step in ST?
The electrical impulse stimulates the release of the neurotransmitter from the synaptic vesicles
What is the fifth step in ST?
Neurotransmitters then carry the signal across the synaptic gap. They bind to receptors sites on the post synaptic cell, which becomes activated
What is the sixth step in ST?
Once the receptors on the post synaptic neuron have been activated they either produce excitatory or inhibitory effects on the post synaptic cell
What is the seventh step in ST?
Excitatory neurotransmitters make the post synaptic cell more likely to fire - dopamine, adrenaline and noradrenaline
What is the eighth step in ST?
Inhibitory neurotransmitters make the posy synaptic cell less likely to fire - GABA and serotonin
What is the ninth step in ST?
Summation is the net effect of EPSPs and IPSPs
What is the lock and key system?
When the specific neurotransmitter (key) meets the receptor (lock) which then opens a membrane
What are excitatory neurotransmitters?
Neurotransmitters that increase the positive charge of the post synaptic neuron - increases the likelihood that the neuron will fire and pass on the electrical impulse
