probably important stuff Flashcards
what is the resting membrane potential mostly due to
k
what is resting membrane potential equal to
-70
what is a somatic sense
sensation in skin and limbs (ie temp)
enteric division
a part of te digestive tract - can act on its own
what carry electrical signals
neurons
whats the control centre of a neuron
cell body (soma)
whats the sensing region
dentrites
where are interneourons locted
entirely within CNS
which nerves have both effereant and afferent properties
spinal nerves
anterograde
forward
retrograde
backwards
fast axonal transport
membrane bound proteins or organeeles
slow axonal transport
cytoplasmic proteins and cytoskeleton proteins
is there retrograde movement in slow axonal transport
no
what drives the walking of proteins along filaments
ATP hydrolysis
CNS glia (4)
ependymal
astrocytes
microglia
oligodentricyte
PNS glia
shwaan cells and satellite cells
myelin forming glia
CNS oligodendrocytes
PNS schwaan cells
satelliote glia cell
`they dont surround the axon they just sit beside it
ependymal cells
line the walls of the brain and spinal cord
what help in PNS regen
shwaan cells
where do graded potentials occur
dendrites and soma
where do action occur
axon hillic and axon terminals
where is the trigger zone
axon hillock
depolarization of what to generste an AP
-55
inactivation gates vs activation gates
they are slow and are open at rest
fast and closed at rest
tonality depends on what solutes
non penetrating
is there ever regeneration on graded potentials
no
can an action potential be summed
no
what happens during the refractory period
two signals too close together in time cannot sum
what is the rule during absolute refractory period
a second AP cannot be regenerated q
what happens during relative refractory period
a second ap can be initiated but require a larger than normal depolarizing stimulus
what ions are in action potentials in neurons
Na and K
what does the refractory period prevent
backwards conduction
where do voltage gated channels exist in myelinated axons
regions of bare axon that cannot be covered by myelin
saltatory conduction
conduct from node to node
what do nodes of ranvier contain
abundance of Na channels
why is conduction faster in myelinated axons
they skip sections (saltatory conduction)
whats faster, electrical or chemical synapse
electrical
is there a refractory period on graded potentials
no
