extra Flashcards
what shows gating
ion channesl
distribution of ion channels
not evenly distributed
what do action potentials rely on
voltage gated channels
what are the two gates in Na channles
activation gate
inactivation gate
what channels are opened at rest
Na and K are closed at rest
what leads to Na channel opening
depolarization
what is the threshold voltage
-50
what underlies the all or none action potentials
Na channesl
explosive depolarization voltage
0
what happnes at the peak of the action potential
Na activation gate begins to close
K channel opens
what happnes during AHP
harder to elicit AP bc membrane is more hyperpolarized
what does membrane repolarization lead to
Na and K channels to return to closed state and are availabel for the next stimulation
what is myelin NOT
it doesnt conduct current
NOT part of axon!!!!!
Aa nerve fibres
propriocption and contraction of skeletal muscles
Ab nerve fibres
touch
Ag nerve fibres
acute pain
C nerve fibres
chornic or dull pain
itch
temp
what shape are SM cells
spindle
axon like fibre transmitting AP in muscle
t tubule
muscle fibre to motor neuron ending
one endplate per cell
a2 muscle fibre
slow twitch
a2 threshold
low threshold
a1 threshold
high threshild
where do motor neurons originate from
spinal chord
a2 contractile forces
greater than a1
what is moved aside by ca2+
tropomyosin
type of muscle in blood vessels
smooth muscle
what are the two division of the efferent division
somatic and autonomic
what does the CNS consist of
brain and spinal chord
what are the effectors and sensro
neurons
what cells play a role in proteciton and support
glial cells
the first two ventricels
two lateral ventricles, one in each side o fht ebrain
where is the choroid plexus
in each ventricle, forms CSF
what does the CSF not contain
no blood cells and little protein
hydrocephalus
problems with CSF formation or reabsorption
