spinal cord Flashcards
- lies within the spinal cavity and extends from the foramen magnum to the lower border of the first lumbar vertebra - oval cylinder that tapers slightly as it descends - 2 bulges, one in cervical region and one in lumbar region
structure of the spinal cord
the 2 bulges in the spinal cord are called:
- cervical enlargement - lumbar enlargement
the anterior median fissure and the posterior median sulcus are two deep grooves; _____ fissure is deeper and wider
anterior
cervical enlargement extends from ___ to ___.
C4 to T1
lumbar enlargement extends ____ to ____.
T9 to T12
termination of the spinal cord. Tapers in a cone shape and ends at the level of the intervertebral disc between L1-2
Conus Medullaris
2 bundles of nerve fibers project from each side of the spinal cord are called
nerve roots
- carry sensory info into the spinal cord
fibers of dorsal (posterior) nerve root
cell bodies of these sensory neurons make up a small region of gray matter called:
dorsal root ganglion
- carry motor info out of the spinal cord
fibers of ventral (anterior) nerve root
cell bodies of these motor neurons are located in the ______ of the spinal cord
gray matter
_____ are located in the spinal cord’s gray matter core
interneurons
on each side of the spinal cord, the dorsal and ventral nerve roots join together to form a single mixed nerve called a:
spinal nerve
the spinal cord ends at:
L1
bundle of nerve roots extending from the conus medullaris at the inferior end of the spinal cord
cauda equina
_____ consists predominantly of cell bodies of interneurons and motor neurons and extend the length of the cord
gray matter
the left and right gray columns are joined in the middle by a band called the:
gray commissure
_____ carries CSF through the spinal cord
central canal
white matter surrounds gray matter and is subdivided in each half of the cord into three columns (funiculi):
- ant - post - lat white columns
Each white column consists of a large bundle of axons divided into tracts. Names of spinal tracts indicate:
- location of the tract - structure in which the axons originate - structure in which they terminate
2 main functions of the spinal cord:
- provides conduction routes to and from the brain - serves as the integrator, or reflex center for all spinal reflexes