HSS 391 Ch. 16: Spinal Cord

An area containing gray matter in the spinal cord are referred to as a _____.

horn

An area containing white matter in the spinal cord are referred to as a _____.

funiculus

An area of connection within the spinal cord is referred to as a _____.

commissure

Anterior horns

Sections of gray matter that contain dendrites and cell bodies of somatic motor neurons (exit via anterior root and travel to effector muscle)

Posterior horns

Sections of gray matter that contain dendrites and cell bodies of interneurons; sensory axons synapse here

Lateral horns

Sections of gray matter located in T1-L2; contain dendrite and cell bodies of visceral motor neurons (sympathetic neurons)

Gray commissure

Section of gray matter that surrounds the central canal and connects gray matter of the left and right sides

White commisure

Section of white matter that connects the two anterior funiculi, beneath the gray matter and gray commissure

Anterior/ventral median fissure

Deep groove on anterior surface of the spinal cord; contains anterior spinal artery

Posterior/dorsal median sulcus

Shallow groove on the posterior surface of the spinal cord

Motor neurons exit on the _____ side of the spinal cord.

anterior/ventral

Sensory neurons enter on the _____ side of the spinal cord.

posterior/dorsar

Anterior/ventral root

Extends from the ventrolateral spinal cord surface; contains axons of somatic motor neurons and visceral motor neurons

Posterior/dorsal root

Extends from the posterolateral spinal cord surface; contains axons of sensory neurons

Posterior/dorsal root ganglion

Swelling on the posterior root that contains cell bodies of sensory neurons & satellite cells

Rootlets

Small branches of nerve fibers from the spinal cord that come together to form anterior & posterior roots

Spinal nerves

Nerves that form when anterior and posterior roots converge; exits vertebral canal through intervertebral foramina

Dura mater

Tough, outer meningeal layer composed of dense irregular CT (1 layer in the spinal cord)

Arachnoid mater

Thin, loose, middle meningeal layer containing web-like extensions comprised of collagen & elastic fibers; creates subarachnoid space for cerebral spinal fluid

Pia mater

Thin, highly vascular, inner meningeal layer of areolar CT in direct contact with spinal cord tissue (inseperable)