synaptic transmission Flashcards
what is synaptic transmission
process by which neighbouring neurones communicate with each other by sending chemical messages across the synapse
what is an action potential
when info is passed down the axon of the neuron as an electrical impulse
what happens once the action potential reaches the end of the axon
(what does it need) (what must it cross over)
it needs to be transferred to another neuron so it must cross over the synaptic gap between the presynaptic neuron and post-synaptic neuron
what are at the end of the neuron
synaptic vesicles
what do synaptic vesicles contain
neurotransmitters known as chemical messengers
what happens when the action potential reaches the synaptic vesicles
they release their NT
after the AP releases their NT what do the NT do
they carry the signal across the synaptic gap
what happens after the NT carry the signal across the synaptic gap
they bind to receptor sites on the post synaptic cell, completing process of synaptic transmission
what are the 2 effects NT can have
inhibitory or excitatory effect
what do inhibitory NT reduce
reduce the potential difference across postsynaptic membrane
how do inhibitory NT reduce the potential difference and what does this reduce
through the closure of the voltage dependent sodium ion channels
this reduces the likelihood an action potential will be generated
what do excitatory NT increase
the potential difference across the postsynaptic membrane
how do excitatory NT increase the potential difference and what does this increase
through triggering the opining of more voltage dependent sodium ion channels
increasing the likelihood an action potential will be generated
what happens if excitatory NT binds to a post synaptic receptor
will cause electrical charge in cell membrane resulting in EPSP
what happens if inhibitory NT binds to a post synaptic receptor
will result in IPSP
