What does the dorsal root contain?

What does the dorsal root contain?

• A. Axons whose cell bodies reside in the ventral spinal cord gray matter
• B. Axons that connect preganglionic autonomic neurons within the spinal cord and a visceral root
• C. Axons whose cell bodies reside in the dorsal root ganglion
• D. Myelinated fibers carrying motor commands from the brain

Answer: (C)

The dorsal root contains the sensory afferent fibers that bring information from the periphery into the spinal cord. The cell bodies of these sensory neurons reside in the dorsal root ganglion, which sits just outside the spinal cord. Each sensory neuron has a peripheral process reaching a receptor and a central process that enters the spinal cord via the dorsal root, conveying sensory data such as touch, pain, and temperature. This is why the correct answer points to axons whose cell bodies reside in the dorsal root ganglion. The other options describe fibers with different roles: motor neurons whose cell bodies are in the ventral gray matter contribute to the ventral root; preganglionic autonomic neuron axons travel in pathways that are not defined by the dorsal root; and fibers carrying motor commands from the brain travel via descending tracts and also exit through the ventral roots rather than the dorsal root.

The dorsal root contains the sensory afferent fibers that bring information from the periphery into the spinal cord. The cell bodies of these sensory neurons reside in the dorsal root ganglion, which sits just outside the spinal cord. Each sensory neuron has a peripheral process reaching a receptor and a central process that enters the spinal cord via the dorsal root, conveying sensory data such as touch, pain, and temperature.

This is why the correct answer points to axons whose cell bodies reside in the dorsal root ganglion. The other options describe fibers with different roles: motor neurons whose cell bodies are in the ventral gray matter contribute to the ventral root; preganglionic autonomic neuron axons travel in pathways that are not defined by the dorsal root; and fibers carrying motor commands from the brain travel via descending tracts and also exit through the ventral roots rather than the dorsal root.