What comprises the central nervous system?

The central nervous system (CNS) is comprised exclusively of the brain and the spinal cord. This system serves as the primary control center for the body, processing information and coordinating activities throughout the organism. The brain processes sensory information, governs thoughts and emotions, and initiates motor functions, while the spinal cord acts as the conduit for signals between the brain and the rest of the body, facilitating communication and reflexes.

The other options mention components that do not belong to the CNS. For example, peripheral nerves, skin, and other systems mentioned are part of the peripheral nervous system (PNS) or other bodily systems, which support but are distinct from the CNS. The PNS includes all the neural elements that exist outside of the brain and spinal cord, such as sensory pathways and motor pathways connecting to muscles and organs. Understanding this distinction is fundamental to grasping the structure and function of the nervous system as a whole.