A & P chapter 13
the ___________ nerve, which arises in the cervical plexus, innervates the diaphragm.
phrenic
blood vessels that supply the spinal cord run along the surface of the?
pia mater
the layer of the meninges in direct contact with the spinal cord is the?
pia mater
the spinal cord consists of four regions and __________ segments.
31
The spinal cord continues to elongate until about age ____.
4
after age _____ , the vertebral column continues to elongate, but the spinal cord itself does not.
4
the spinal cord is part of the ________ nervous system.
CNS
In an adult, the conus medullaris is found at about?
L1
the dorsal root of a spinal nerve contains?
axons of sensory neurons
the obturator nerve is distributed to the?
adductors of the hip
postganglionic fibers of the autonomic nervous system that innervate internal organs are?
autonomic nerves
the ventral root of a spinal nerve contains?
axons of motor neurons
spinal nerves are?
both sensory and motor
in which plexus does the ulnar nerve arise?
brachial
the ventral rami of spinal nerves C5 to T1 contribute fibers to the _________ plexus.
brachial
the white matter of the spinal cord contains?
bundles of axons with common origins, destinations and functions
the dorsal root ganglia mainly contains?
cell bodies of sensory neurons
muscles of the neck and shoulder are innervated by spinal nerves from the __________ region.
cervical
in the spinal cord, white matter is separated into ascending and descending tracts organized as ?
columns
the ____________ of each spinal nerve innervates the skin and muscles of the back.
dorsal ramus
which branch carries motor neurons to structures on the back of the body trunk?
dorsal ramus
the tough, fibrous, outermost covering of the spinal cord is the?
dura mater
the layer of connective tissue that surrounds individual axons within a peripheral nerve is termed the?
endoneurium
the outermost connective tissue covering of the nerves is the?
epineurium
The ____________ is a strand of fibrous tissue that provides longitudinal support to the spinal cord as a component of the coccygeal ligament.
filum terminale
axons crossing from one side of the spinal cord to the other within the gray matter are found in the?
gray commissures
the preganglionic fibers that connect an autonomic ganglion in the thoracic or lumbar region with the spinal nerve and contain postganglionic fibers that innervates glands in the body wall or smooth muscles in limbs are?
gray rami communicantes
the outward projections from the central gray matter of the spinal cord, seen easily in microscopic spinal cord cross sections are called?
horns
reflexes based on synapses formed during development are_________ reflexes.
innate
which of the following is true regarding an epidural block?
it is commonly used as a method of pain control during labor and delivery, it affects only spinal nerves in the immediate area of injection, it can be difficult to achieve upper cervical and midthoracic region, it provides mainly sensory anesthesia
a viral disease that destroys the cells of the anterior gray horn will?
lead to muscular weakness or paralysis
spinal nerves from the sacral region of the cord innervate the _______ muscles.
leg
bill contracts a viral disease that destroys cells in the posterior gray horns in his spinal cord. As a result, which of the following would you expect?
loss of sensation in his torso
if a person has a crush injury to the c3-c5 spinal segments, you would expect that he?
might be unable to breathe on his own
the white matter of the spinal cord is mainly?
myelinated and unmyelinated axons
the gray horns of the spinal cord contain mainly?
nerve cell bodies
the layer of connective tissue that surrounds a fascicle within a peripheral nerve is the?
perineurium
the complex interwoven network formed by contributions from the ventral rami of?
plexus
as the ___________ nerve approaches the knee, it divides into two branches, the fibular nerve and the tibial nerve.
sciatic
if the dorsal root of a spinal nerve is severed ........
sensory input would be blocked
the posterior horns of the spinal cord contain mainly?
sensory nuclei
in the condition ______________ , is a virus infects dorsal root ganglia, causing a painful rash whose distribution corresponds to that of the affected sensory nerves as seen in their dermatomes.
shingles
the anterior horns of the spinal cord contain mainly
somatic motor nuclei
in which structure are sensory cell bodies located?
spinal ganglia
the specialized membranes that surround the spinal cord are termed the?
spinal meninges
A dorsal and ventral root of each spinal segment unite to form a?
spinal nerve
cerebrospinal fluid flows within the?
subarachnoid space
samples of CSF for diagnostic purposes are normally obtained by placing the tip of a needle in the?
subarachnoid space
the reflex that prevents a muscle from exerting too much tension is the ________ reflex.
tendon
the subdural space lies between. .......
the dura mater and the arachnoid mater
into what spinal area would one inject a chemical whose purpose is to anesthetize the patient?
the epidural space
the __________ innervates the ventrolateral body surface, structures in the body wall and the limbs.
ventral ramus
nerve tracts or fasciculi make up the?
white columns
the preganglionic fibers that connect a spinal nerve with an autonomic ganglion in the thoracic and lumbar region of the spinal cord and carries visceral motor fibers that are myelinated form the?
white rami communicantes