What are the steps of depolarization?
- depolarization of presynaptic terminal
- Ca entry
- exocytosis of transmitter
- postsynaptic receptor action potential
- Ion channels open in post synaptic membrane
____________ is caused by G(k)> G(Na)
hyper polarization
If potassium current> sodium current, the membrane potential will tend to move toward E(k)
equilibrium of potassium
___________ no net flux of ions occur
resting potential
_________ active change in membrane potential via via changing ionic conductances.
action potential
Ohms law in terms of conductance
I= G(Vm-Ek)
simulus -> membrane depolarization -> Na+ channels open (ΔGna) change in sodium conductance
stimulus -> membrane depolarization -> Na+. channels open (ΔGna) -> Na floods into cell -> action potential
change ion __________ and current drive action potentials
conductance
___________ TTX blocks voltage gated sodium channels. No outward current
TTX tetrodotoxin
_____________ blocks potassium channels. No outward current
TEA tetra ethyl amine.
high _____________ inside the cell
potassium
hugh _________________ outside the cell
sodium
__________________ allowed resting conditions to be maintained
sodium potassium pump
________________ sodium channels are inactivated
absolute refractory period
______________ much harder to reach action potentials. Larger current needed. If generated, the action potential will be small due to the conductance of Gnarling not resetting and not as many sodium channels
relatively refractory period
________________:
- quick rapid adapting response
- allows us to determine small changes
phasic response
______________:
- slow adapting
- help us determine the length of adaptation
tonic response
___________ electrical coupling, the allows for instaneous neural signaling. Caused by two neurons being tightly opposed. Allows the cytoplasm to be tightly opposed
Gap junctions
How were gap junctions found
- dye coupling
- Vm change
steps of synaptic physiology
Depolarizing of presynaptic terminal -> Ca entry -> exocytosis of transmitter -> postsynaptic receptor act. -> ion channels open in postsynaptic membrane
