The central nervous system (CNS) is the processing center for the nervous system. It receives information from and sends information to the peripheral nervous system. The two main organs of the CNS are the brain and spinal cord.he brain processes and interprets sensory information sent from the spinal cord. Both the brain and spinal cord are protected by three layers of connective tissue called the meninges. Within the central nervous system is a system of hollow cavities called ventricles.
The edge of something is the end of it, the outer limit. You can sit on the edge of your desk, on the edge of a chair, on the edge of a cliff. As stated by someone else, sitting on the edge of your seat is used to indicate tension or anticipation. You are ready to jump up out of the seat as quickly as possible.
(ÉdÊ) n., v. edged, edgâ¢ing. n. 1. a line or border at which a surface terminates: Grass grew along the edge of the road. 2. a brink or verge: the edge of a cliff; the edge of disaster. 3. any of the narrow surfaces of a thin, flat object: a book with gilt edges. 4. a line at which two surfaces of a solid object meet. 5. the thin, sharp side of the blade of a cutting instrument or weapon. 6. the sharpness proper to a blade: The knife has lost its edge. 7. a quality of sharpness or keenness: Her voice had an edge to it.