The Afferent Neuron That Carries the Sensation and Enters the CNS

Question

The afferent neuron that carries the sensation and enters the CNS is a ________ neuron.
A) receptor
B) first-order
C) second-order
D) third-order
E) fourth-order

Accepted Answer

First-order neurons are afferent neurons that carry sensory information from the periphery to the central nervous system. They typically have cell bodies located in dorsal root ganglia (for somatic sensory information) or sensory ganglia of cranial nerves (for cranial nerve sensory information). Receptor neurons are specialized cells that detect stimuli and are often the first step in sensory processing, but they do not enter the CNS directly. Second, third, and fourth-order neurons are involved in relaying and processing the sensory information within the brain and spinal cord.