Lecture 17: Spinal Cord Flashcards
What are the three regions of the somite?
dermatome
myotome
sclerotome
What is a dermatome?
area of the skin supplied with afferent nerve fibers by a single posterior spinal root
What is a myotome?
all the muscles that are innervated by a single efferent anterior root. Most muscles are composed of more than one myotome.
Where is the cervical enlargement?
C3-T1
Where is the lumbar enlargement?
L1-S2
Where does the conus medullaris end?
L2
Gray matter (horns) are equivalent to ____
CNS nuclei
The posterior gray horns receive _____
incoming sensory fibers
The anterior gray horns are the site of ____
cell bodies of alpha Moto neurons to skeletal muscle fibers
The lateral gray horns are located in the _______ region and site of ______
thoracic and upper lumbar; cell bodies of autonomic neurons
The white matter columns consist of ______
myelinated tracts
The dorsal roots carry ____ fibers
afferent
Ventral rootlets and root carries _____ fibers
efferent
The spinal carries _____ fibers
both efferent and afferent
Where does the dorsal primary rami go?
epaxial musculature and skin on either side of dorsal of back
Where does the ventral primary rami go?
to hypaxial musculature and rest of skin
What does the autonomic white ramus communicans carry?
pre ganglionic sympathetic fibers from lateral horns of central gray of spinal cord
What does the autonomic gray ramus communicans carry?
post ganglionic sympathetic fibers from paravertebral ganglia back to spinal nerves
What is the order of the meningeal coverings and spaces?
epidural space dura mater subdural space arachnoid subarachnoid space pia mater denticulate ligaments
