Which structure within the inner ear is primarily involved in transducing mechanical energy into neural signals?

Which structure within the inner ear is primarily involved in transducing mechanical energy into neural signals?

• A. Outer ear structures such as the auricle.
• B. Auditory nerve fibers.
• C. Cochlea in the inner ear.
• D. Tympanic membrane.

Answer: (C)

Transduction of mechanical energy into neural signals happens in the cochlea, the sensory organ of hearing in the inner ear. Sound causes vibrations that travel through the fluids of the cochlea, making the basilar membrane move. This motion deflects the stereocilia of the hair cells in the organ of Corti. When the hair bundles bend, mechanically gated ion channels open, allowing ions to flow and the hair cell to depolarize. This depolarization opens voltage-gated calcium channels, triggering the release of neurotransmitter onto the afferent spiral ganglion neurons whose fibers form the auditory nerve. The neural signals are then conveyed to the brain. Outer-ear structures and the tympanic membrane primarily help capture and transmit energy to the inner ear, while the auditory nerve carries signals; the actual energy-to-neural transduction occurs in the cochlea.

Transduction of mechanical energy into neural signals happens in the cochlea, the sensory organ of hearing in the inner ear. Sound causes vibrations that travel through the fluids of the cochlea, making the basilar membrane move. This motion deflects the stereocilia of the hair cells in the organ of Corti. When the hair bundles bend, mechanically gated ion channels open, allowing ions to flow and the hair cell to depolarize. This depolarization opens voltage-gated calcium channels, triggering the release of neurotransmitter onto the afferent spiral ganglion neurons whose fibers form the auditory nerve. The neural signals are then conveyed to the brain. Outer-ear structures and the tympanic membrane primarily help capture and transmit energy to the inner ear, while the auditory nerve carries signals; the actual energy-to-neural transduction occurs in the cochlea.