CHAPTER 14 Flashcards
true or false? spinal reflexes do not involve the brain.
true
Which is faster, a reflex or a response? Why?
a reflex, because information does not have to travel very far or be processed by the brain
the inferior end of the spinal cord tapers to form a point called the
conus medullaris
Typical length and diameter of an adult’s spinal cord
3/4 in diameter, 16-18 in length
True or false? the spinal cord spans the entire length of the vertebral column.
false
The spinal cord has 2 longitudinal depressions. what are they called?
posterior median sulcus and anterior median fissure
four parts of spinal cord
cervical, thoracic, lumbar, sacral
2 widened regions of spinal cord, with greater number of neurons
cervical and lumbar enlargements
Why do the enlargements of the spinal cord have more neurons?
they innervate their corresponding limbs
spinal cord meninges
pia, arachnoid, dura
delicate layer (meninge) adhering to spinal cord
pia mater
lateral extensions of pia, help suspend spinal cord
denticulate ligaments
filum terminale
pia anchoring inferior end of spinal cord to coccyx
web-like external layer to pia
arachnoid mater
arachnoid trabeculae
fibrous extensions of the arachnoid mater
subarachnoid space
area deep to arachnoid mater through wich CSF flows
tough, outermost of the spinal cord meninges
dura mater
Where is the epidural space in relation to the dura mater, and what can be found there?
between the dura and vertebra. it houses adipose and areolar connective tissues, as well as blood vessels
procedure for obtaining CSF for medical diagnosis
lumbar puncture
Where to lumbar puncture?
just above or below L4
Masses of grey matter that project from the center of the spinal cord
“horns”
which of the horns houses axons of sensory neurons and bodies of interneurons?
posterior
which horn houses cell bodies of somatic motor neurons?
anterior
Which horn houses cell bodies of autonomic motor neurons?
lateral horns
Regions of white matter found on spinal cord
funiculi
which funiculus contains sensory tracts (axon bundles called fasciculi)
posterior
Which funiculus contains sensory (ascending) and motor (descending) tracts?
lateral
Which funiculus has its left and right connected by the white commissure?
anterior
Primary neuron
neuron has a peripheral ending, cell body in posterior root ganglion, and axon leading to secondary neuron
secondary neuron
neuron is an interneuron; receives primary input and extends to tertiary neuron or to cerebellum
tertiary neuron
interneuron; receives secondary neuron input and extends to somatosensory cortex of parietal lobe of cerebrum
segment of skin supplied by single spinal nerve
dermatome
network of interweaving anterior rami of spinal nerves
nerve plexus
4 main plexuses
cervical, brachial, lumbar, sacral
True or false: the 4 main plexuses occur bilaterally
true
What is innervated by the smaller nerves of the lumbar plexus?
abdominal wall, portions of external genitalia
Can superior or inferior gluteal nerves be injured by poorly placed gluteal injection?
yes.
Sciatica is characterized by ________
extreme pain down posterior thigh and leg
