What is Nerve?

A whitish cordlike structure composed of one or more bundles (fascicles) of myelinated or unmyelinated nerve fibers, or more often mixtures of both, coursing outside the central nervous system, together with connective tissue within the fascicle and around the neurolemma of individual nerve fibers (endoneurium), around each fascicle (perineurium), and around the entire nerve and its nourishing blood vessels (epineurium), by which stimuli are transmitted from the central nervous system to a part of the body or the reverse. Nerve branches are given in the definition of the major nerve; many are also listed and defined under branch.