The coordinator – brain or spinal cord – determines whether or not to respond to the stimulus. Conjunctiva Thin, transparent protective outer covering that prevents entry of microorganisms.

Information from receptors passes along neurones, as electrical impulses to co-ordinators such as the central nervous system or CNS ... change in the environment (stimulus) and stimulate ...

Now any stimulus, verbal or nonverbal, which presents itself to the nervous system changes the bio-chemistry of your nervous system. If you want to play the labelling game you can call some of ...