THE EAR

How you hear
The ear is made up of three parts: the outer ear, the middle ear, and the inner ear. The outer ear consists of the auricle (pinna) and the external auditory canal. The middle ear consists of the tympanic membrane (eardrum), the ossicles (malleus, incus and stapes), and the Eustachian tube. The inner ear consists of the cochlea, the vestibular system, and the auditory nerve. The auricle collects sound waves which are funneled by the external auditory canal to the tympanic membrane. The sound waves hit the tympanic membrane and set the ossicles into vibration. This vibration moves the footplate of the stapes in and out of the cochlea's oval window. The fluid inside of the cochlea is set into motion generating nerve impulses. These nerve impulses are then transmitted by the auditory nerve to the brain, where they are heard as sound.