Nervous System Flashcards
Consists of a cell body, dendrites and an axon
Neuron
a bundle of 100’s to 1000’s of axons often with associated connective tissue and blood vessels
Nerve
Outer layer, Covers the brain, brainstem, spinal cord, rootlets and spinal nerves
Dura matter (Dura=tough mother)
Middle layer, Loosely organized connective tissue with a spider web-like appearance
Arachnoid Matter
Intimately associated with nerves, spinal cord and brain. Thin, deepest/ innermost layer
Pia Matter (pia= soft mother
Originate from the anterior aspect of the cord
Carries outgoing motor information only
No associated ganglion
Anterior Roots
Originate from the posterior aspect of the cord
Carries incoming sensory information
Has Ganglion
Posterior Roots
a collection of nerve cell bodies located outside of the CNS
Ganglion
Anterior and Posterior roots come together to form… Travels through intervertebral foramina
Spinal Nerves
Innervate muscles and structures of the upper and lower limbs
Also innervate skin of the lateral and ventral (anterior) surfaces of trunk
Anterior Primary Rami (branch anteriorly)
Innervate deep muscles of the back
Also innervate skin of the dorsal (posterior) surface of the trunk
Posterior Primary Rami (branch posteriorly)
How many pairs of spinal nerves for Cervical region
8 pairs
How many pairs of spinal nerves for Thoracic region
12 pairs
How many pairs of spinal nerves are in the Lumbar region
5 pairs
How many pairs of spinal nerves for Sacral region
5 pairs