Which structure is not located within the CNS?

Which structure is not located within the CNS?

• A. Spinal cord
• B. Cerebellum
• C. Dorsal root ganglion
• D. Medulla oblongata

Answer: (C)

The difference between the CNS and the peripheral nervous system is being tested here. The structure that is not located within the CNS is the dorsal root ganglion, because it belongs to the peripheral nervous system. It sits along the dorsal root of a spinal nerve just outside the spinal cord and contains the cell bodies of sensory neurons. The central processes of those neurons enter the spinal cord to transmit sensory information. In contrast, the spinal cord, cerebellum, and medulla oblongata are all components of the CNS, residing within the brain and spinal column.

The difference between the CNS and the peripheral nervous system is being tested here. The structure that is not located within the CNS is the dorsal root ganglion, because it belongs to the peripheral nervous system. It sits along the dorsal root of a spinal nerve just outside the spinal cord and contains the cell bodies of sensory neurons. The central processes of those neurons enter the spinal cord to transmit sensory information. In contrast, the spinal cord, cerebellum, and medulla oblongata are all components of the CNS, residing within the brain and spinal column.