What are the two types of hair cells in the cochlea?

What are the two types of hair cells in the cochlea?

• A. Inner hair cells (primary afferent signal generators) and outer hair cells (contribute to cochlear amplification)
• B. Inner hair cells and supporting cells
• C. Outer hair cells and supporting cells
• D. Basilar membrane cells

Answer: (A)

In the cochlea, there are two kinds of hair cells with distinct roles. Inner hair cells are the main sensory transducers that convert mechanical vibrations into neural signals sent to the brain via afferent auditory nerve fibers. Outer hair cells, on the other hand, act as mechanical amplifiers; their electromotile movements enhance and sharpen basilar membrane motion, boosting sensitivity and frequency discrimination. Supporting cells and other basilar membrane–associated cells are not hair cells, so they don’t represent the two primary types. Therefore, the pair that best fits is inner hair cells and outer hair cells, with the highlighted functional distinction.

In the cochlea, there are two kinds of hair cells with distinct roles. Inner hair cells are the main sensory transducers that convert mechanical vibrations into neural signals sent to the brain via afferent auditory nerve fibers. Outer hair cells, on the other hand, act as mechanical amplifiers; their electromotile movements enhance and sharpen basilar membrane motion, boosting sensitivity and frequency discrimination. Supporting cells and other basilar membrane–associated cells are not hair cells, so they don’t represent the two primary types. Therefore, the pair that best fits is inner hair cells and outer hair cells, with the highlighted functional distinction.