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Flashcards in Action Potentials Deck (50)
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31

what is AP propagation

local current flow to adjacent area
raise pot to threshold
voltage gated N channel open
poitve feedback
porpaget along axon

32

what si a refractory period

time when cannot reactivate a Na channel

33

what are th two types of refractory period

absolute and relative

34

what is an absolute refractory period

Na channels not in rest configuration
an AP can't occur

35

what is a relative refractory period

K gates open
mem is hyper polarised
an AP can occur need larger stimulus

36

what does a refractory period do in terms of directions

means that nerve signals cannot backfire only propagated in one direction

37

what does the width of an axon do to conduction velocity

increase axon diameter
lower resistance
faster conduction

38

what does myelination do to conduction velocity

insulates
node ranvier jumps
local current flow node to node
depo jumps

39

what re the types of nerve fibres

C
A delta
A beta
A alpha

40

what does a C nerve do

slow burning pain
high resistance coz thin and non myelin
smallest nerve slow velocity

41

what is a A delt nerve

faster sharp pain
myelin sheath so faster condition and is wider

42

what is a A beta nerve

wider and myelinated
sensory ones, mechanoreceps

43

what is a A alpha

biggest nerve
motor to muscles
widest and myelinated

44

why rent all nerve A alpha

to big to fit in body need small to fit in places or would be huge

45

what re incoming nerves

afferent from periphery to centre

46

what are outgoing nerves

efferent from center to periphery

47

what are the fastest nerves linked to

proprioception - knowing about self form and what body doing

48

what is good to keep in mind about nerve size with dentistry

affects diff with LA

49

what are the easiest yes of nerves to block

smallest most difficult widest

50

what are he first type of nerves to be blocked

pain then touch