The Nervous System

The nervous system is a complex network of billions of neurons, or individual nerve cells. These cells send and receive messages while you are awake and while you are asleep. They also allow different parts of your body to communicate, including your muscles and your glands. Nerve cells are the primary system of communication within the brain, and between the brain and the rest of the body.

Although slower than the nervous system, the endocrine system also helps different parts of your body to communicate. The endocrine system controls the chemical reactions that happen in all of the systems through the release of hormones. In this topic, you will learn more about how these systems communicate with the body, allowing it to maintain homeostasis and function properly.

Essential Questions

• What are the parts and functions of the nervous system?
• How are messages sent back and forth from the brain to body?
• What are the key components of the endocrine system, and how does this system communicate with the body and brain differently than the nervous system?