intro to NS - neural and gilial structure Flashcards
what are the subdivisions of the NS
PNS and CNS
what is the CNS made up of
brain and SC
PNS
somatic and autonomic NS
what is the ANS composed of
para and sympathetic
in the somatic NS what are the components
sensory components in and motor out
one of each axon
component of autonomic NS
2 cells carry info out
synapse between cells
what does the somatic NScontrol
strained muscle for voluntary actions
what is the somatic system composed of
31 spinal nerves
12 CN
what do neurones consist of
cell body
axon
dendrites
what does the cell body contain
nucleus and cellular organelles
what is the membrane potential determined by
concentration of ions inside and out
permeability of the cell membrane to ions
activity of the pumps
what occurs at resting potential
3 Na pumped out 2K pumped In
membrane permeable to K
negative charge on inside of cell
what happens when threshold is reached
action potential generated
sodium ion channel opens - positive charge inside the neurone
what happens after sodium ion channels opened
(depolarisation)
channels shut
potassium channels open, K leaves cell leading to hyperpolarization
how can action potential generation and propagation be blocke
sodium channel blockers no ionic movement
