This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Chapter 13 Spinal Cord and Spinal Nerves Pages 460 469; 480 490 A. External Anatomy of the Spinal Cord: Fig 13.2 Spinal Cord- Flattened slightly anterior and posteriorly. (42-45 cm and 2 cm thick; 16-18 inches long, terminates at L1-L2 junction ) Extends from the medulla oblongata to the superior border or 2 nd lumbar vertebra. o Spinal cord stays the same while the spinal (vertebral) column grows when you become an adult. o Spinal Nerve ends with corresponding vertebrate ie C1 nerve exit at C1 vertebrate. o Cerebrospinal fluid, vertebral column protects the spinal cord. Cervical Enlargement The superior enlargement extending from 4 th cervical vertebra to 1 st thoracic vertebra All nerves in the upper limbs of the body (Arms) come from here. o Vertebrate starts to become thicker. Lumbar Enlargement- The inferior enlargement extending from the 9-12 thoracic vertebra. All nerves in the lower limbs of the body ( legs) come from here o Vertebrate starts to become thicker. Conus medullaris- Where the spinal cord terminates as a tapering, conical structure that ends at the intervetebral disc between first and second lumbar. Pia Mater- Innermost layer...goes to this. Filum terminale- An extension of the pia mater that extends inferiorly and anchors the spinal cord to the coccyx. Cauda equina The roots of the spinal cord nerves (two bundles of axons). Like a horses tail, wisps Lumbar, Sacral, Coccygeal spinal cord roots and exits through its corresponding vertebrate. Processing of information by the spinal cord: Fig 13.4 Butterfly/H-Shaped Gray Matter, and surrounding it is white matter. Propagate nerve impulses (white matter) o Posterior Columnswhite matteralso anterior and lateral columns. Some are only sensory tracts. Integrating information from sensory neurons (Gray Matter). o Can go up the white matter in ascending tract. o Synapse with interneuron and go on the other side of the brain and go up ascending tract o Sensory neuron can synapse directly with motor neuron by going down descending tracts....
View Full Document