nervous system

the complete system of tissues and CELLS , including NERVES , NEURONS , SYNAPSES and RECEPTORS ( a special cell sensitive to a particular stimulus which then sends an impulse through the nervous system). The nervous system operates through the transmission of NERVE IMPULSES that are conducted rapidly to and from muscles, organs, etc. It consists of the CENTRAL NERVOUS SYSTEM (brain and spinal cord) and the PERIPHERAL NERVOUS SYSTEM , which includes the CRANIAL NERVES and spinal nerves (see AUTONOMIC NERVOUS SYSTEM ).