3. Cervical enlargement Lumbar enlargement Conus medullaris- the terminal end of the spinal cord Cauda equina - collection of spinal nerves transversing the inferior end of the vertebral column Filum terminale- fibrous extension of the pia mater

6. Posterior horn -projections of gray matter Anterior horn-projection of gray matter Gray commissure -central area of gray matter connecting two vertical regions Central canal -surrounded by gray commissure and contains CSF Posterior funiculus -white matter on eiter side of the fissures Anterior funiculus -white matter on either side of the fissures Posterior median sulcus -deep to the posterior median sulcus Anterior median fissure -open anterior fissure

7. Dorsal root -where the fibers enter the dorsal horns Dorsal root ganglion -enlargement of dorsal root Ventral root –fibers enter the ventral root Spinal nerve -formed by the fusion of dorsal and ventral roots Cervical plexus -arises from the ventral rami c1-C5 and supplies muscles of neck and shoulder Brachial plexus -arises from ventral rami C5-C8, T1 ans supplies arm to fingertips Lumbar plexus -arise from ventral rami L1-L4 and supplies the lower and upper abdominopelvis region, and anterior thigh Sacral plexus -arise from L4-S4 and supplies the buttock, posterior thigh, and all sensory and motor fibers in leg and foot