The organ of Corti is located in which structure?

• A. Vestibule
• B. Semicircular canals
• C. Auditory canal
• D. Cochlea

Answer: (D)

The organ of Corti is the hearing sensory organ located inside the cochlea of the inner ear. The cochlea is a spiral, fluid-filled structure, and the organ of Corti sits on the basilar membrane within the cochlear duct (scala media). When sound waves move through the cochlear fluids, they cause the basilar membrane to vibrate, bending the hair cell stereocilia in the organ of Corti and converting mechanical energy into electrical signals that travel to the brain via the auditory nerve. The vestibule and semicircular canals are involved in balance, not hearing, and the auditory (external) canal is just the outer passage for sound to reach the middle ear. So, the organ of Corti is in the cochlea.