Final answer:
The spiral organ, or Organ of Corti, converts sound vibrations into nerve impulses, which allow the brain to perceive sound. This process involves hair cells within the cochlea that respond to vibrations by bending their stereocilia and initiating nerve signals.
Step-by-step explanation:
The spiral organ, or Organ of Corti, is essential for transducing sound vibrations into nerve impulses. Located in the cochlea of the inner ear, it houses hair cells with hair-like extensions called stereocilia that are embedded in or contact the tectorial membrane above. When sound vibrations travel through the cochlea, they vibrate the tectorial membrane, bending the stereocilia and triggering a cascade of biological processes in the hair cells that results in the generation of nerve impulses. These impulses are sent to the brain via the cochlear nerve which allows for the perception of sound.
There are two types of hair cells in the spiral organ: inner and outer hair cells. The approximately 3,500 inner hair cells act as the primary auditory receptors, while the roughly 12,000 outer hair cells fine-tune the sound waves. The activation of these cells depends on the intensity and pitch of the sound waves, enabling us to discern different sounds.The organ of Corti contains hair cells that detect the vibrations and convert them into electrical signals that can be transmitted to the brain through the auditory nerve.