Synapse I Flashcards
A synapse is a specialized ______ between neurons at the end of an _____
junction; axon
Synapses are considered _____ (presynaptic/postsynaptic)
directional
Synapses convert action potentials into a ____ signal, also known as a ______
chemical; neurotransmitter
Synaptic _____ contain neurotransmitters and the action potential causes them to fuse with the ___-synaptic membrane
vesicles; pre
Neurotransmitters are released into the _________ which is the space between the neurons via action potenital
synaptic cleft
The transmitter binds to _____ (proteins) in which membrane?
receptors; postsynaptic
Binding of transmitters to receptors first opens the ____, then activates the _____ and lastly causes a response in the ___-synaptic neuron.
ion channel; enzyme; post
Each neuron typically receives 1k-10k synapses, although most are located on the ____
dendrites
An action potential opens ____ gated ____ channels in the axon terminal.
voltage; calcium
Calcium influx causes what structure to fuse with the presynaptic membrane, causing neurotransmitter release into the synaptic cleft?
synaptic vesicles
Neurotransmitters bind to which receptor?
postsynaptic
If the receptor is an ion channel, the channel ____, ions flow ___ the postsynaptic neuron, and causes postsynaptic _____.
opens; into; potential
Vesicles are recycled, meaning that new vesicles bud off from which membrane? What is this process called?
presynaptic; endocytosis
Neurotransmitters are synthesize locally where?
in the axon terminal
Neurotransmitters are loaded into vesicles by _____ proteins and into the ___ membrane.
transport; vesicular
What is the difference between ionotropic and metabotropic?
ionotropic = opens ion channel
metabotropic = g-protein coupled, causes production of 2nd messenger, activates kinase –> modifies proteins
Which type of synapse opens ion channels?
ionotropic
Which type of synapse use signal transduction mechanisms such as g-proteins?
metabotropic
Protein kinases modify the function of many different proteins that change what about the neurons?
their electrical excitability
What are the 2 main types of postsynaptic potentials?
EPSP: excitatory
IPSP: inhibitory