Describe structure and function of the spinal cord

Describe structure and function of the spinal cord -...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Describe structure and function of the spinal cord. Major reflex center: spinal reflexes are initiated and completed at the spinal cord level. Pathway for nerve impulses to and from the brain. Spinal cord is protected by bone, CSF, and meninges. 31 pairs of spinal nerves arise from the cord by paired roots and exit the column via the intervertebral foramen to travel to the body regions they serve.The cord has two obvious enlargements (cervical and lumbar) where the nerves serving the upper and lower limbs arise. The lumbar and sacral spinal nerve roots angle sharply down ward and travel inferiorly through the vertebral column for some distance before reaching their foramina. The nerve roots at the inferior end are called the cauda equina (horse's tail). In cross section, gray matter appears in a shape of a butterfly (consists of neuron cell bodies, unmyelinated axons, and dendrites) and white matter is exterior (myelinated axons of tracts).
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Describe gray matter of spinal cord. Gray matter is subdivided into regions called horns (anterior, posterior, and lateral). Anterior horns are largest in the regions serving the limbs - associated with voluntary motor activity. Lateral horns contain autonomic motor neurons that serve visceral organs. Motor fibers leave the cord via the ventral root. Sensory fibers come into the cord via the dorsal root. Sensory neuron cell bodies are located in the dorsal root ganglion. Dorsal and ventral roots fuse to form spinal nerves. . Describe white matter of spinal cord. Composed of myel;nated fibers that travel up brain and brainstem (sensory), down from brain and brainstem (motor), and across from one side of the cord to the other. White matter is made up of tracts - multineuron pathways that connect brain to body periphery. Ascending tracts are sensory. Descending tracts are motor....
View Full Document

Ask a homework question - tutors are online