Synaptic Transmission Flashcards
what are electrical gap junctions?
voltage is transferred via touching membranes and signals may pass in both directions
what are chemical synapses?
signals are transferred through ion channels from the pre- to post-synaptic neuron
what is the presynaptic neuron?
neuron that conducts action potential toward the synapse
what is the post synaptic neuron?
neuron whose action potentials are propagated away from the synapse
what is the synaptic knob?
contains synaptic vesicles
what are synaptic vesicles?
stores neurotransmitter (carries signal across a synapse)
what is the synaptic delay?
time needed for the conversion of the electrical signal from the presynaptic neuron to an electrical signal in the postsynaptic neuron by chemical means
what ends the signal at the postsynaptic membrane?
the removal of neurotransmitter through either:
diffusion
enzymatic degradation
reuptake
what is diffusion in ending the signal?
movement away from the synaptic cleft
what is enzymatic degradation?
inactivation by specific enzymes within the synaptic cleft
what is reuptake?
actively taken back up into the presynaptic axon terminal
can be recycled or destroyed by enzymes within the synaptic knob
what are the common neurotransmitters?
acetylcholine
norepinephrine
GABA (inhibitory in the CNS)
