MEDICAL ANIMATION TRANSCRIPT: The spinal cord begins at the brainstem, exits the skull through the foramen magnum, and extends to the first lumbar vertebra, divided into cervical, thoracic, lumbar, and sacral regions. The spinal cord gives rise to pairs of spinal nerves that supply sensory and motor function to the body. The cauda equina, made up of lumbar and sacral spinal nerves, extends through the vertebral canal from L2 to S5. The spinal cord is composed of gray matter and white matter. Gray matter contains nerve cell bodies, dendrites, and the proximal parts of axons. White matter contains spinal tracts which consist of myelinated axons. Sensory nerve impulses travel from the body to the brain through afferent nerves in the dorsal root ganglion and dorsal root. Motor nerve impulses travel from the brain to the body, through efferent nerve axons in the ventral root. Dorsal and ventral roots merge to form each spinal nerve. The American Spinal Injury Association classifies spinal...