Which region of the spinal cord contains motor neuron cell bodies?

Which region of the spinal cord contains motor neuron cell bodies?

• A. Ventral horn of the spinal cord
• B. Dorsal horn of the spinal cord
• C. Median ventral fissure
• D. White matter of the spinal cord

Answer: (A)

Motor neuron cell bodies sit in gray matter, and for controlling skeletal (voluntary) muscles they reside in the ventral (anterior) horn of the spinal cord. The axons exit through the ventral roots to innervate muscles. The dorsal horn contains sensory interneurons and processing of incoming sensory information, not motor neuron cell bodies. The white matter is made up of myelinated axons carrying signals between brain and spinal cord, not cell bodies. The median ventral fissure is simply a groove on the ventral surface, not a site for motor neuron somata. (Note: autonomic motor neurons can be in the lateral horn at certain levels, but for somatic motor control the ventral horn is the region with motor neuron cell bodies.)

Motor neuron cell bodies sit in gray matter, and for controlling skeletal (voluntary) muscles they reside in the ventral (anterior) horn of the spinal cord. The axons exit through the ventral roots to innervate muscles. The dorsal horn contains sensory interneurons and processing of incoming sensory information, not motor neuron cell bodies. The white matter is made up of myelinated axons carrying signals between brain and spinal cord, not cell bodies. The median ventral fissure is simply a groove on the ventral surface, not a site for motor neuron somata. (Note: autonomic motor neurons can be in the lateral horn at certain levels, but for somatic motor control the ventral horn is the region with motor neuron cell bodies.)