What are the two main divisions of the nervous system?

• A. Central nervous system and peripheral nervous system
• B. Autonomic nervous system and somatic nervous system
• C. Brain and spinal cord
• D. Cerebrum and cerebellum

Answer: (A)

The nervous system is organized into two main divisions: the central nervous system and the peripheral nervous system. The central nervous system includes the brain and spinal cord and acts as the control center, processing information and coordinating responses. The peripheral nervous system consists of all nerves outside the brain and spinal cord, linking the CNS to muscles, glands, and sensory receptors so signals can be transmitted to and from the body. This framework helps explain how signals travel: the CNS interprets and plans actions, while the PNS carries those messages to and from the rest of the body. The autonomic and somatic systems are subdivisions within the peripheral nervous system, handling automatic functions versus voluntary control, while the brain and spinal cord are parts of the central nervous system, and the cerebrum and cerebellum are major brain structures, not divisions.