The Inner Ear (Cochlea) is where transduction takes place.
The Inner Ear: The function of the Outer and Middle ear was to conduct sound energy to the Inner Ear where the actual transduction takes place. The Inner Ear is usually referred to as the Cochlea (in dark green in the picture on the next screen).
It is basically a tube filled with fluid and embedded in the Temporal bone. Unlike the porous bone surrounding the Middle Ear Cavity, the Temporal bone has the highest density of any bone matter in the body.
This is probably a testimony to the delicate nature of this mechanism and its need for protection.
The tube is wound around a central core so that it would resemble a snail shell. At its base are three other tubes, which we have discussed before. These are the Semi Circular Canals of the Vestibular sense (in light green in the picture on the next screen).