Spinal Cord Flashcards
What is the general shape of the spinal cord in cross section?
Oval
What depression lies on the anterior surface of the spinal cord?
Anterior median sulcus
What depression lies on the posterior surface of the spinal cord?
Posterior median sulcus
Where does the spinal cord begin in an adult?
Foramen magnum
Where does the spinal cord end in an adult?
L1
How does the dura mater within the vertebral canal different from the dura within the cranial cavity?
It consists of one layer rather than two
What portion of the spinal cord is composed of dendrites and cell bodies of neurons and glial cells and unmyelinated axons?
Gray matter
What portion of the spinal cord is composed of myelinated axons?
White matter
Within the spinal cord where is gray matter located and how is it shaped?
Centrally butterfly shaped
Within the spinal cord what are the anterior masses of gray matter that contain the cell bodies of somatic motor neurons?
Anterior horns
Within the spinal cord from T1-L12 what structures contain the cell bodies of autonomic motor neurons?
Lateral horns
Within the spinal cord what are the posterior masses of gray matter that contain the axons of sensory neurons and the cell bodies of internerouns?
Posterior horns
What horizontal bar of gray matter surrounds the central canal within the spinal cord?
Gray commissure
What fills the central canal of the spinal cord?
Cerebrospinal fluid
Within the regions of the spinal cords gray matter what are the various functional groups of neuron cell bodies?
Nuclei
Where does the white matter of the spinal cord lie in relation to the gray matter?
External
Anteriorly and posteriorly what are the small attachments of a spinal nerve to the spinal cord?
Rootlets
Rootlets converge to form what structures?
•Anterior root
•Posterior root
The cell bodies of sensory neurons associated with the spinal cord are found in what structures?
Posterior root ganglion
The cell bodies of motor neurons within the spinal cord are found in what structures?
Anterior horn
How many pairs of spinal nerves are there?
31
What is cauda equina?
Spinal nerves that extend after the end of the spinal cord
What are the two main branches of a spinal nerve?
•Posterior ramus
•Anterior ramus
What branches of a spinal nerve are associated with the autonomic nervous system?
Communicating rami
What is a specific segement of skin supplied by a single spinal nerve?
Dermatomes
