The ear is made up of an outer part, a middle part and an inner part.

The outer ear is made up of the pinna or auricle and the ear canal. The pinna is the part that sticks out, that we can see and the ear canal is where earwax is made. Earwax helps keep the insides of our ears clean, it’s nice and sticky to trap any specs of dirt that enter. The job of the outer ear is to act as a funnel, collecting sound and taking it through the ear canal which leads to the middle ear.

The middle ear transforms sound waves into vibrations. It is separated from the outer ear by the eardrum or tympanic membrane, this is a special kind of drum. When sounds waves hit the eardrum, it vibrates. These vibrations move three tiny bones in the ears called ossicles which help carry the vibrations to the inner ear. 

The three bones are called the hammer, anvil and stirrup. 

The hammer or malleus is attached to the eardrum.

The anvil or incus is attached to the hammer.

The stirrup or stapes is attached to the anvil. It’s the smallest bone in the entire body!

The inner ear changes vibrations into nerve signals which are sent to the brain. It is made up of the cochlea and semicircular canals. 

The cochlea is shaped like a snail and has liquid inside. This liquid moves when the tiny bones from the middle ear start to vibrate. When the liquid moves it creates nerve signals which travel to the brain along the cochlear nerve (auditory nerve).

The semicircular canals are three tubes which are all connected, they have fluid inside and are lined with little hairs. Their job is to help us keep balance. When the fluid inside moves, it moves the hairs. This creates signals which go to the brain through the vestibular nerve letting the brain know about our position. The brain will then send messages to our muscles to stop us from falling down.

The cochlear nerve sends sound information to the brain and the vestibular nerve sends balance information to the brain and together they make the vestibulocochlear nerve.

Looking after the ears

Now you know how important ears are, you’re going to want to look after them. You can keep them clean by washing them with water, just like you wash the rest of your body. Be careful not to put small items in the ears, even things like fingernails can scratch the eardrum. 

The ear does a lot of work to let us hear, the last thing you want to do is make its job even harder by damaging your hearing. Listening to very loud music, especially with headphones, is not wise and it can cause permanent damage.

Interesting facts 

• Spiders hear through the hairs on their legs.

• If we have too much earwax it can be hard to hear, especially if it’s pressed against the eardrum.
• Earwax normally comes out of the ear naturally.
• To hear properly, the pressure must be equal on both sides of the eardrum. When you go in a plane or lift, the air pressure changes and your ears can make that pop sound.
• A tube that connects the middle ear to the back of the nose called the eustachian tube adjusts the pressure, acting like a pressure valve and balances it on both sides of the eardrum.
• Ear infections are more common in children because of the differences in their eustachian tubes and because their immune systems are not as developed as adults.