The end result is the simplest form of etching. There are more complicated ways to create more intricate etchings by using a number of different plates and colors. There is also a process to add different tones to the image that involves adding resin dust to the plate and heating it.
Nerves carry electrochemical signals to and from different areas of the nervous system as well as between the nervous system and other tissues and organs. Nerves are divided into four classes: Cranial nerves connect your sense organs (eyes, ears, nose, mouth) to your brain.
The central nervous system is the brain and spinal cord. The peripheral nervous system is everything else like the sensory nerves that let you know when you cut your finger or the nerves that tell your toes to wiggle. Every part of the nervous system is made up of structures called neurons.