What are the two main divisions of the nervous system?

The two main divisions of the nervous system are the central and peripheral nervous systems. The central nervous system (CNS) comprises the brain and spinal cord, which serve as the primary control center for processing sensory information and coordinating responses. It is responsible for higher functions such as thought, emotion, and movement coordination.

The peripheral nervous system (PNS), on the other hand, encompasses all the nervous tissue outside the CNS. This includes sensory and motor neurons that extend to the limbs and organs. The PNS is crucial for relaying information between the CNS and the rest of the body, facilitating communication between these parts.

While the autonomic and somatic nervous systems are subdivisions of the peripheral nervous system, they cannot be considered the main divisions of the entire system. Similarly, the sympathetic and parasympathetic nervous systems are components of the autonomic nervous system, focusing on involuntary responses. The option referring only to the brain and spinal cord highlights a part of the central nervous system but does not encompass the entire nervous system's structure. Therefore, identifying the central and peripheral nervous systems captures the full scope of how the nervous system is organized.