biopsychology - synaptic transmission Flashcards
what is syaptic trasnmission
process byw hich neighbouring neurons communciate with eahc otehr by sending chemical messages across the syanpse that seperates them
how do neurons communcicate with eahc other
within groups known as neural networks
eahc neurons seperated fromthe next by
extrmeley tiny gap called synapse
signals within neurons are tramsitted
electrically
signals between neurons are transmitted
chemically across the synapse
the end of the neurons is called
presynaptioc terminal
when an electrical impulse reaches the end of the neuron(presyanptic terminal) what happens
it triggers the release of the neurotrasnitter from tiny sacs called synaptic vesicles
neurotransmitters
going on now
what are neurotrasmitters
chemicals that diffuse across the synapse to the next neuron in the chain
once a neurotrasnitter crosse the gap waht ahppens
its taken up by a postsynaptic receptor site on the dendrites of the next neuron
where do axons take signals
to the synapse
where do dendrites take signals
away fromt eh synapse
once a neurotrasnitter crosse the gap its taken up by a postsynaptic receptor site on the dendrites of the next neuron what happens here
teh chemical message is converted back into an electrical impulse and the process of transmission begins again in this other neuron
the direction of travel can only be
one way
why can the diretion of travel only be one way
nt are releasd from teh presyanptic neuron terminal and recieved by the postsyanptic neuron (at receptor sites)
several dozen types of nt have been idenitfied where
in the brian
(as well as spinal cord and glands)
each neurotransmitter has its own x structure that ….
specific molecular structure
that
fits perfectly into a postsyanptic receptor site
similar ot a lock and key
nt also have specilisat function true or flase
true
each nt has its own specialist funciton for instance tell me about acetylcholine
found at eahc point where a motor neuron meets a muscle
upon its release cuases muscles ot contract
excitaiton and inhibition
neurotransmitter have 1 of 2 effects name them
excitatory
inhibitory
on neighbouring neurosn
for instance nt serotinin causes inhibition in the recieving neuron what does thi smena
results in the neuron becoming more -vley charged and less liekly to fire
adrenaline is both a
neurotrasmitter
hormone
adrenaline cuases excitation of the postynaptic neuron what does this mean
it increass its +Ve charge making it more likely to fire
summation
whether a psotynaptic enuro fire is decided by
the process of summation
explain summaitno
excitatory and inhibtirory influences are summed
if net effect on post synaptic neuron is inhibitory the post syanptic neuron is less liekly to fire
if net effect is excitatory its more likely to fire , i.e inside of the postsynaptic neuron moemtarily beocmes +vley charged
once electrical impulse is created it travels down the neuron
therfore the actino ptoenial of teh postsyanptic neuron is only triggered if the sum of the excitatory and inhibitory signals at any one time reaches the threshold
what is action potential
Information is passed down the axon of the neuron
