Our ears enable us to pick up sounds from our surroundings, listen and reply to other people, and enjoy music. The structure of the ears is primarily adapted to clearly pick up sound, although it also contains the vestibular system that provides our sense of balance.
The external part of the ear that we can see is called the pinna or auricle. It is made of cartilage and skin. Sound is collected by the pinna and funnelled into the outer ear canal. The sound makes the tympanic membrane (eardrum) vibrate.
These vibrations, in turn, are picked up and amplified by three tiny bones (ossicles) called the malleus, incus and stapes, in the middle ear. To ensure that the sound quality is clear, the Eustachian tube balances the air pressure in the middle ear.
Sound waves entering the inner ear pass through the cochlea, which looks like a snail shell. Nerve endings in the cochlea convert these vibrations into electrical impulses that are carried by the auditory nerve into the brain, which processes it into hearing.