Indicate where the brain and the spinal cord are on a diagram of the human body. Their location at the top and core of the body is partially why they are known as the "central" system.
Explain how they are defined in simple terms. The brain is often known as the "headquarters" of the body, while the spinal cord is the "main manager" of the central system. Without the brain and spinal cord to tell the body what to do and communicate with the body's PNS, a person would not be able to live.
Note the similarities in each component's construction by observing visual details of nerve cells in the CNS. Both the brain and spinal cord contain hundreds of billions of nerve cells and extensions. The small extensions are called dendrites, while the longer ones are called axons.
Point to the two sides, or hemispheres, of the brain. Describe their roles and the way that networks of axons connect them.
List or discuss the eight parts of the hemispheres. Describe what they do. For instance, the midbrain monitors vision, eye movement and body movement. The basal ganglia regulates movement, while the limbic system controls emotions, memory and learning through its subparts.
Make a chart on a separate piece of paper regarding what is voluntary and involuntary in the CNS. While the brain is the center of conscious thoughts, the brain and spinal cord also execute bodily systems without people realizing them. For instance, a person does not think about or decide to digest food --- her body does it for her. All bodily systems and organs are managed through this involuntary information transmission that begins in the brain.
Define "peripheral," which means secondary or external system. Explain that despite being secondary to the brain and spinal cord, the center of the body's functioning, the PNS is vital to human existence. It is through the PNS that all voluntary information in the brain is transmitted to the body.
Name the two parts of the peripheral system, the somatic nervous system (SNS) and the autonomic nervous system (ANS). Point on the diagram to the places they meet the brain and spinal cord, which are through the long chains of nerves and connectors.
Point to the skin and sensory organs such as the eyes, hands, nose, ears and bones to describe the role and function of the SNS. The SNS is responsible for carrying information to and from these body parts --- processing the information along the way --- to the CNS. It is through the PNS that, for instance you can see, feel and hear and move your bones and muscles.
Point to the veins, mouth and skin to describe the role of the ANS. Nerves connecting to veins and capillaries ensure that blood pressure is regulated (which is accomplished by the increase and decrease in size of the vessels). The ANS also monitors the need to sweat based on the temperature of the body. These are involuntary systems that do not require conscious thought.
Trace a finger back and forth along the spinal cord out to the limbs. The peripheral nervous system brings messages to the brain and then transmits messages from the brain to the rest of the body.