The Ear

The ear has the ability to hear different ranges of sound. Most people can hear between 20 hertz and 20,000 hertz.

The ear plays a role to help us to hear.

Parts of the Ear

The ear is made up of different parts such as the pinna, outer ear canal, eardrum, hammer, anvil, stirrup, cochlea, semicircular canals, eustachian tubes, and nerves.

Helix
Tubercle
Scapha
Antihelix
Concha
Antitragus
Lobe
Triangular Fossa
Legs of Antihelix
Leg of Helix
Anterior Notch
Position of Auditiry Meatus
Intertragical Notch

Pinna and Outer Ear Canal

The pinna, sometimes called the auricle, is the part of the outer ear that we can see.

The pinna is useful in hearing because it helps to collect the sound and then directs the sound to the outer ear canal.

The outer ear canal is a tube that sound, as it enters in the pinna, travels and goes to the eardrum.

Hammer, Anvil and Stirrup

The hammer, also called the malleus, is a super small bone that helps to take vibrations and transport them to the anvil.

The anvil, also known as the incus, is a super small bone that takes the sound from the hammer and transports it to the stirrup.

The stirrup, also called the stapes, is the smallest bone in the human body, smaller than all other bones.

This is sometimes called a “U” shape because it looks like a letter U.

The stirrup transmits the sounds from the hammer and the anvil and sends them to the cochlea.

Cochlea

The cochlea is a structure that is found in the inner ear and it is a spiral shaped structure.

Inside of the cochlea are super small hairs that are called cilia and these hairs move when vibrations occur.

When the vibration hits the cilia, the moving cilia makes a nerve impulse.

Semicircular Canals

There are three different canals located in the ear that are semicircular. These are tubes that are filled with fluid and they loop around the ear.

These tubes are attached to the cochlea, inside of the inner ear, and these canals help to make sure that we have balance.

Eustachian Tube

The Eustachian tube connects the back of the nose to the middle ear. This tube helps to make sure that the pressure of the middle ear and the air on the outside are equalized so that you hear good and that you do not lose balance.

When a person goes up a mountain and feels like their ear “pops” or when someone swallows and their ear “pops” this is the Eustachian tube that is equalizing the pressure in the middle ear.

Nerves

Signals from the inner ear are carried to the brain by nerves.

These nerves send signals to the brain to help the brain interpret what the sound is.

Ear Diseases

There are a few common ear diseases, but the most common are vertigo and deafness.

Vertigo is when a person has improper balance because of pressure that is inside the ear. This disease can cause you to be dizzy or to feel unbalanced.

Deafness can occur due to carelessness or from birth defects.

It is important not to listen to music too loud and to wear earplugs or other protective gear when you will be around loud sounds.

Facts About the Ear:

  • Ears never stop working.
  • The earlobe is always growing.
  • Ears clean themselves by making wax that collects the oil and other substances from getting down inside of the ear.
  • The cilia help to hear. If you lose your hair out of your ears, you lose your hearing.

What Did You Learn?

  • What is interesting about the bones in the ear? The interesting thing about bones in the ear is that the ear has the smallest bone in the body.
  • How does sound travel through the ear? Vibrations travel from the hammer to the anvil and then to the stirrup to other parts of the ear, eventually leading to the brain.
  • What role does the brain play in hearing? Vibrations travel and create sounds that cause nerves to travel to the brain. The brain can then interpret the sound.
  • What part of the ear never stops growing? The earlobe never stops growing.
  • What is Vertigo? Vertigo is an ear disease that causes people to be dizzy or off balance.