What are the two main divisions of the nervous system?

• A. Central nervous system (CNS) and peripheral nervous system (PNS)
• B. Sympathetic and parasympathetic nervous systems
• C. Cranial and spinal nerves
• D. Autonomic and somatic systems

Answer: (A)

The two main divisions of the nervous system are the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS consists of the brain and spinal cord, which serve as the control center for processing information and coordinating responses. The PNS includes all the nerves that extend from the spinal cord and brain to the rest of the body, allowing communication between the CNS and limbs or organs. This division is crucial because it helps organize how the body processes sensory information and executes motor commands.

The sympathetic and parasympathetic systems refer to components of the autonomic nervous system, which is a part of the PNS, rather than being separate divisions of the entire nervous system. Cranial and spinal nerves are subsets of the PNS but do not encompass the CNS. The autonomic and somatic systems explain functional subdivisions within the PNS but do not address the overall framework of the nervous system.