Most sensory afferent pain fibers enter the spinal cord by way of the ________ nerve roots.

• A. dorsal
• B. lateral
• C. ventral
• D. anterior

Answer: (A)

Verified step by step guidance

1. Understand the anatomy of the spinal cord: The spinal cord is divided into regions, and nerve roots are categorized as dorsal (posterior) and ventral (anterior). These roots are responsible for transmitting different types of signals.
2. Recall the function of dorsal nerve roots: Dorsal nerve roots are primarily responsible for carrying sensory information, including pain signals, from the peripheral nervous system to the central nervous system.
3. Contrast dorsal and ventral nerve roots: Ventral nerve roots are involved in motor function, transmitting signals from the central nervous system to muscles, while dorsal nerve roots handle sensory input.
4. Identify the pathway of pain signals: Pain signals, as part of sensory afferent fibers, travel through the dorsal nerve roots to enter the spinal cord.
5. Select the correct answer based on the function: Since sensory afferent pain fibers are associated with sensory input, they enter the spinal cord via the dorsal nerve roots.