Synapse Flashcards
structure electrical synapse
gap junction
gap junction, what is permeability regulated by?
cytosolic concentration of free ca2+ or cytosolic ph
gap junction, what kind of complex does it have?
hexameric
6 connexins form a
connexon
electrical synapse also permit
synchronization of activity
synchronization, in neurons that have a
similar function
gap junctions, permits movement of ?
atp and second messengers
chemical neurotransmitters are? and eg?
small molecules in small clear vesicles
ach, gaba, glutamate, glycine
chemical neurotransmitters, large molecules in dense core vesicles
neuropeptides
release of chemical neurotransmitters is
ca dependent
neural basis of learning and memory, 2 changes
functioning of neurons in brain could change
structure of neurons could change
electrical properties
instantaneous
no loss of signal
similar time course
chemical properties
delayed
signal greatly reduced
longer response
advantage of electrical signal
no synaptic delay
allows synchronization of many cells quickly
can transmit metabolic signals between cells
disadvantage of electrical signal
cannot convert signal from pre to post, from excitatory to inhibitory
chemical synapse, glytamate
opens na+ channels,
excitatory
chemical synapse, GABA
opens cl- channels
inhibitory
spatial summation
eg if 3 neurons fire the individual signal is all below threshold,
when the signals build up together they are able to go and create suprathreshold signal
action potential
temporal summation
if 2 subthreshold potentials arrive at the trigger zone within a short period of time they may sum and initiate a action potential
