Final answer:
The cochlea is the part of the inner ear where soundwave energy is transduced into neuronal impulses by bending the stereocilia on hair cells, initiating electrical signals sent to the brain via the auditory nerve.
Step-by-step explanation:
The receptor cells that transduce soundwave energy into neuronal impulses are located within a fluid-filled structure called the cochlea. The process of transducing sound involves sound waves entering the ear, causing the eardrum to vibrate. These vibrations are then transferred through the bones of the middle ear and ultimately reach the cochlea. Within the cochlea, the vibrations cause the basilar membrane to move, which bends the stereocilia on the hair cells of the organ of Corti. This bending leads to a change in electrical potential in the hair cell, resulting in the sending of auditory signals through the auditory nerve to the brain.