Question

you step on a sharp object and almost immediately feel pain from it! the sensory signal from your foot would travel up the spinal cord and to the brain.
which horn of the spinal cord would the neuron carrying the pain signal enter?

a. anterior gray horn
b. posterior gray horn
c. lateral gray horn

Explanation:

Identify the signal type

Using the Sensory and Motor Pathways knowledge point
The scenario describes stepping on a sharp object and feeling pain. Pain is a somatic sensory sensation.

Determine the entry point in the spinal cord

Using the Spinal Cord Anatomy knowledge point
Sensory information enters the spinal cord via the dorsal (posterior) root. The cell bodies of these pseudounipolar sensory neurons reside in the dorsal root ganglion, and their central axons project into the posterior (dorsal) gray horn of the spinal cord to synapse with second-order neurons.

Compare with the given options

• Anterior Gray Horn: Contains somatic motor nuclei that send motor signals to skeletal muscles.
• Posterior Gray Horn: Contains somatic and visceral sensory nuclei that receive incoming sensory signals.
• Lateral Gray Horn: Located only in thoracic and upper lumbar segments, containing autonomic motor nuclei.

Therefore, the pain signal enters the posterior gray horn.

Answer:

• a. Anterior Gray Horn
• b. Posterior Gray Horn (Correct answer)
• c. Lateral Gray Horn