Gross anatomy of the Middle Ear - Boundaries , Contents and Functions (Animation) The ear can be split into three parts; external, middle and inner. The middle ear lies within the temporal bone, and extends from the tympanic membrane to the lateral wall of the inner ear. The main function of the middle ear is to transmit vibrations from the tympanic membrane to the inner ear via the auditory ossicles. Parts of the Middle Ear The middle ear can be divided into two parts: Tympanic cavity – located