ch 14 Flashcards
where does the spinal cord end
l1/l2
cauda equina
bundle of nerves at the end of the spine that looks like a horses tail
terminal filum
hold spinal cord tight
how are spinal nerves named
what vertebra the nerve exits under
dura mater
surrounds outer portion of spinal cords
arachnoid matter
fiberous, thinner, spiderweb like, middle layer to protect spinal chord
pia mater
thin, fine, surround spinal chord, closes to chords
epidural space
fat above durra (mater), this is where epidural is stuck (l3/l4)
subarachnoid space/ lumbar cistern
below arachnoid matter,
where cerebral spinal fluid is present
gray matter
contains somas and dendrites
horns in cross section of vertebra
white matter
myelinated axons
containing tracts (nerves/ funiculi)
ascending tract
carry sensory info to brain (up)
descending tract
carry motor info from brain
decussate/ decussation
origin of tract is contralateral to destination
tracts that dont cross midline
ipsilateral
posterior gray horn
lateral gray horn
sympathetic nerve neuron (fight or flight)
posterior grey horn
sensory/ afferent nerves
interneuron
anterior gray horn
somatic/ motor neruons
(a) first order neuron
receptor to spinal cord/brain
(a) second order
spinal cord to thalamus (deems info important)
no repectors
(a) third order
thalamus to cerebral cortex/ front lobe
decussation can occur in
FIRST OR THIRD ORDER ONLY
medulla or spinal chord
motor neurons involved in descending tracts
2
upper and lower