T2: Nervous System Flashcards
Two main divisions of NS
CNS
PNS
Is grey and white matter on inside or of brain and spinal cord
Brain= grey outside SC= grey inside
2 parts of PNS
Sensory + motor
how does the sensory and motor each split into two sub groups
somatic/ visceral
the visceral motor division splits into what
sympathetic /para
what are the 3 universal properties of neutrons
- excitable
conduct
secretion (neurotransmitter)
what force does somatic motor and visceral motor produce each
somatic= somatic reflex + contraction visceral= visceral reflex
how is RMpotential maintained and at what voltage
-70, movement of ions
explain summation of postsynaptic changes to get over threshold
threshold reaching requires sum of all signals (net change)
what forms myelin sheath in CNS and PNS
C= oligodendrocytes P= schwann
what does nodes of ranvioer and +concentrations of NA in gaps do
create areas of low and max resistance
what does nerve signal speed depend on
diameter + myelin
describe 3rd week neuron development
ectoderm thicken= neural plate + folds inward= neural groove
neuro fold fuse
describe 3rd week neuron development
neuro folds completely fuse= neural tube (brain + spinal cord)
what is the neural crest
=surrounds sides of neural tube
3 primary vesicles of neural tube
Forebrain (prosencephalon)
midbrain (mesencephalon)
hindbrain (rhombencephalon)
secondary vesicles of the prosencephalon + brain structures
telencephalon = hemisphers diencephalon= thalamus ect
secondary vesicles of the mesencephalon + brain structures
stays midbrain
secondary vesicles of the rhombencephalon + brain structures
metencephalon= pons, cerebellum myelencephalon= medulla oblongata