What does the dorsal root ganglion contain?

• A. Dorsal root ganglion
• B. Dorsal root
• C. Anterior horns
• D. White matter

Answer: (A)

This question tests what a dorsal root ganglion is. A dorsal root ganglion is a cluster of neuron cell bodies in the peripheral nervous system, specifically the bodies of sensory neurons. The sensory neurons have their peripheral processes reaching sensory receptors and their central processes entering the spinal cord. Because a ganglion is defined by containing cell bodies, the dorsal root ganglion houses these sensory neuron somas. The dorsal root itself is made up of the axons of these sensory neurons as they travel toward the spinal cord, not the cell bodies. In contrast, the anterior (ventral) horns of the spinal cord contain motor neuron cell bodies, and white matter consists of myelinated axons outside the gray matter. So, the dorsal root ganglion contains the cell bodies of sensory neurons.