AT THE EDGE
Our Complex Nervous System
Our nervous system has three major parts: central, peripheral, and autonomic. The central nervous system consists of the brain and spinal cord. It controls the body's voluntary actions as well as some involuntary actions, such as reflexes. The peripheral nerves connect all the body's tissues and organs to the central nervous system. The autonomic system, a complex subset of the peripheral nervous system, controls involuntary activities, such as heart rate, temperature, and intestinal motility.
Neural tissue in all three systems is made up of neurons (nerve cells) and associated glial cells. Neurons consist of a round …