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The ear is the organ of hearing and balance. As you can see in the diagram it is made up of the outer, middle and inner ear.
The folds of cartilage that surround the ear canal are called the pinna. Sound waves travel down the ear canal until they reach the eardrum, causing it to vibrate.
The middle ear is an air-filled space that links the outer ear with the inner ear.
Within the middle ear there are three tiny bones called the ossicles (or the incus, malleus and stapes). When the eardrum vibrates, it causes the ossicles to move backwards and forwards. This movement passes the sound waves through to the inner ear.
The Inner Ear has two parts:
1) The cochlea, responsible for hearing.
The cochlea is a fluid-filled chamber that looks a bit like a snail shell. It is lined with thousands of tiny sensory cells known as hair cells. When sound waves enter the cochlea, the hair cells change the vibrations into electrical signals.
2) The vestibular system, responsible for balance.
The vestibular system is also filled with fluid and has three small sections lined with hair cells. When you move your head, the fluid within these sections moves. In response to this movement, hair cells create electrical signals that are sent to the brain.