Basics of the Nervous System

Lesson Plan - Get It!

Audio:

Just like the electrical lines outside that are responsible for moving information to and from your house, there is an electrical system in your body that moves messages and data.

Your nervous system processes information collected from your environment to coordinate your body systems. There are two branches of the nervous system: the central nervous system and the peripheral system. These two work together to ensure that the body is functioning and responding to stimuli, or changes in the environment.

The central nervous system is comprised of the brain and the spine. The brain and spine are cushioned by special fluid that protects them from damage or injury, called cerebrospinal fluid. This is the fluid that is taken during a spinal tap procedure.

Your brain is made up of nerve cells that take in information collected by nerves running throughout your body and provide instructions for response.

The brain connects to the spinal cord, which runs from your neck to your pelvis. It is a pathway between the brain and the nerve cells in your arms and legs.

Once messages have moved from the brain to the spinal cord, they are then transmitted by the peripheral nervous system. The peripheral nervous system directs automatic functions like heart contractions and voluntary muscle movements in your fingers and legs, and assists nerves with controlling impulses.

All these nerves are made up of neurons, specialized cells designed to allow for movement of electrical impulses from one end to the other.

Notice how the cell has many branches. Each branch allows for faster movement of information through the body. At the meeting point between two cells, there is a synapse. This is an area with a neurotransmitter that helps identify the type of information and direct it to where it will be used.

Nerves also collect information from the outside world and send messages back to the brain along the same pathway. This is how you know to sweat when you become hot and shiver when you become cold. The central nervous system and the peripheral system work together to ensure that your body is identifying and responding appropriately to changes in your environment.

Each component in your nervous system has a specific job that aids with communication of, and response to, information.

• Without your nervous system, how would your body respond?
• Which component do you think is the most important part of the system?

Reflect in your notebook before moving to the Got It? section, where you will review the major components of the nervous system.