Exam #1: Lab 2 Flashcards
What is the cervical enlargement?
Roots of the brachial plexus coming off the cervical spinal cord= larger cord
What do the ventral primary rami become in the thoracic spinal cord?
Intercostal nerves
What is the lumbar enlargement?
Area of the cord that innervates the lower limb
What is the conus medullaris? Where is the conus medullaris?
~L1 the end of the spinal cord
What is the filuman terminale?
Pia mater anchor for the spinal dura at the end of the spinal cord
Where is the gray matter?
“Butterfly” in the middle of the cord; this is the unmyelinated neuronal cell bodies, axons & dendrites
Where is the white matter/
Outside of the butterfly
How does the white:gray matter ratio of the cervical cord compare to other regions? Why?
In the cervical cord there is much more white matter b/c this is the ascending & descending tracts of myelinated axons & dendrites from all of the body
Where is the anterior horn on the cross-section of the spinal cord? What does the anterior horn contain?
Anterior horn= bottom of the butterfly that contains motonuerons
Where is the dorsal horn on the cross-section of the spinal cord? What does the dorsal horn contain?
Wing-tips of the butterfly that contain sensory neurons
Where is the lateral horn on the cross-section of the spinal cord? What does the lateral horn contain?
Preganglionic cell bodies of the SNS—T1-L2
What is the ventral median fissure?
Wide/ deep groove that is specific for the ventral aspect of the spinal cord
What is the dorsal median sulcus?
Shallow groove in the dorsal part of the spinal cord
What is & where is the dorsal faniculus/ posterior faniculus?
This is the white matter between the two dorsal/ posterior horns i.e. the wingtips of the butterfly
What is & where is the lateral faniculus?
This is the white matter lateral to the two dorsal/ posterior horns i.e. the wingtips of the butterfly
What is & where is the anterior faniculus?
This is the white matter anterior to the ventral horns i.e. the body of the butterfly
How does the white:gray matter ratio change in the lumbar spinal cord? Why?
Less white & more gray matter b/c the descending motor tracts have “left” gone to the upper body & sensory tracts only contain information from the lower limb
What is the anterior horn?
Body of the butterfly that contains cell bodies of the lower motoneurons
How is the posterior/ dorsal horn of the gray matter divided?
The posterior horn is divided into “Rexed’s Lamina”
What are the major division of the posterior horn that we are responsible for? What is their function?
Substantia gelatinosa—”Rexed’s Lamina II” = pain & temperature
Nucleus proprius= pain & temperature
What is Lissauer’s Tract?
- This is a white matter tract that sits just outside of the posterior horn; it is also called the “dorsolateral tract”
- This bundle of myelinated axons comes from cell bodies of sensory neurons located in the dorsal root ganglion (DRG)
Where are the DRG in relation to Lissaruer’s Tract?
DRG sits outside of the cord in the proximal spinal nerve. Axons of the DRG exit the spinal nerve & enter the spinal cord to form “Lissauer’s Tract.”
What is the function of Lissauer’s Tract?
Pain
Temp
Crude touch fibers
How does the pons appear on gross dissection?
Swollen portion of the brainstem
