PHYL 2041 Lecture Notes - Lecture 13: Cerebrospinal Fluid, Lumbar Puncture, Cranial Nerves
Document Summary
We discriminate between the pns (consists of all the nerves leaving the cns and going to and fro from all structures of the body) and the cns (consists of the brain and spinal cord). The top of the brain is dominated by the two large cerebral hemisphere. There are other structures like the cerebellum, and then the spinal cord. The spinal cord has segmented nerves between each pair of vertebrate. Nerves leaving and entering the spinal cord unit and forms the segmented nerves. The other side of the picture illustrate the sympathetic chain, which also leaves and enters particularly the thoracic and lumbar region for the sympathetic system. At where the spinal cord enters the lumbar region, the solid structure of the spinal cord breaks down and we end up with very fine nerves running in parallel together and forming peripheral nerves. Although in the thoracic region, you get separate nerves leaving each vertebrate and going out to the periphery.