The term peripheral nervous system (PNS) refers to one of two components of the nervous system defined by dissection; the other component is the central nervous system (CNS). The PNS includes the cranial nerves, the spinal nerves, the peripheral ganglia and plexuses to which they attach, and the peripheral nerves that attach those to the skin, muscles and other end organs. The nerves are composed of neuronal fibers that conduct sensory information from, and motor control information to, the end organs ( Carpenter-1983 ). The short segments of the fibers that run between central nuclei and the surface of the brain or spinal cord are referred to as 'nerve fibers' and are considered parts of the CNS. The longer segments of the fibers that run in the nerves attached to the brain and spinal cord belong to the PNS ( Swanson-2004 ).