chapter 13 - the spinal cord and spinal nerves Flashcards
where does the spinal cord run?
medulla oblongata to the conus medullaris
what is the spinal cord covered by?
meninges
what are the layers of the meninges?
dura mater, arachnoid matter, pia mater
what is the innermost layer of the meninges?
pia mater
what is the outermost layer of the meninges?
dura mater
what runs between the dura mater and the wall of the vertebral canal?
epidural space
what lies between the dura mater and arachnoid mater?
subdural space
what lies between the arachnoid and pia mater?
subarachnoid space
what contains cerebrospinal fluid?
subarachnoid space
what contains interstitial fluid?
subdural space
what is an extension of the pia mater?
denticulate ligament
where is the cervical enlargement located?
vertebrae c4-t1
where is the lumbar enlargement located?
t9-t12
what is the cone shaped end of the spinal cord?
conus medularis
what is the continuation of the conus medlars?
cauda equina
what is an extension of the conus (pia) connecting the inferior end fo the spinal cord to the coccyx?
filum terminalae
how many spinal nerves are there?
13
how many cervical nerves are there?
8
how many lumbar nerves are there?
12
how many lumbar nerves are there?
5
how many sacral nerves are there?
5
how many coccygeal nerves are there?
1
what carries sensory information into the spinal cord?
posterior (dorsal) root
what contains sensory axons?
dorsal root
where does information leave the spinal cord?
anterior (ventral) root
what contains motor axons?
ventral root
what contains incoming sensory information?
posterior (dorsal) horn
what contains somatic motor neurons?
anterior (ventral) horn
where does autonomic motor neurons begin?
lateral horn
what horn is found only in the thoracic and upper lumbar?
lateral horn
where does sensory information go?
through the back
where does motor information go?
out the front
what is a cluster of nerve cell bodies in the PNS?
ganglion
what is a cluster of cell bodies inside the CNS?
nucleus
what is a bundle of axons located in the PNS?
nerve
what is a bundle of axons inside the CNS?
tracts
what forms the cervical plexus?
anterior rami of c1-c5
c3, 4, 5 keeps the diaphragm alive
what forms the brachial plexus?
c5-c8, t1
what plexus supplies the shoulders and upper limbs?
brachial plexus
what makes up skin and muscle of the head and neck, superior part of the shoulders and chest, and diaphragm?
cervical plexus
what is responsible for wrist drop?
radial nerve injury
what is responsible for carpal tunnel?
median nerve injury
what does the median nerve supply?
most of the flexors of the forearm
what is responsible for claw hand?
ulnar nerve injury
what causes scapular winging?
long thoracic nerve
what forms the lumbar plexus?
l2-l4
what forms the sacral plexus?
anterior rami of l4-l5 and s1-s4
what is an area of skin that provides sensory input to the CNS via one pair of spinal nerves?
dermatome
what is a pathway that a nerve impulse follows to produce a reflex?
reflex arc
what reflex causes contraction of skeletal muscle in response to stretching of a muscle?
stretch reflex
what reflexes controls muscle tension by causing relaxation before muscle force becomes too great?
tendon reflex
what reflex causes withdrawal of a body part in response to a painful stimulus?
flexor (withdrawal) reflex
what causes contraction of a muscle opposite to the stimulus?
crossed extensor reflex
what is a disorder of a dermatome?
shingles/herpes zoster
