The Nervous System controls an organism's actions and sends messages throughout the body using nuerons. The sensory nuerons helps the body respond to stimulus such as light, touch, and sound and coordinate the response to this stimulus. In the human body, the main organs of this system are the brain and spinal cord, with nerves connecting these organs to the rest of the body. Every species has its own unique nervous system, fit to its lifestyle. For example, a parasite may have a simpler nervous system since it does not need to coordinate as many actions as a human. The parasite has all of its needs within its host.
Here is a diagram of the human nervous system, the most advanced of any species
Important Links:
www.britannica.com
www.livescience.com
www.NFW.org
www.pennmedicine.org
www.britannica.com
www.livescience.com
www.NFW.org
www.pennmedicine.org
Here is a diagram depicting a nueron and its many parts. Neurons are messengers of the nervous system.