17 Autonomic Nervous System

Our nervous system is not just centralized in our heads. It runs through the entire body. But why does the nervous system need to spread around the body? Let's think about the last time you had a big exam. Before taking the exam, you probably had butterflies in your stomach. You may have even felt your heart racing, your skin sweating, and your head pounding. It seems like the mere thought of the exam in your brain is enough to prod the rest of your body to prepare for action.