A-Cérumen

From the outer to the inner ear

The ear has two functions: balance and hearing. It consists of three parts, each of which plays a role in hearing:  

  • The outer ear picks up sound waves. It is in this precise area that earwax is developed.
  • The middle ear transforms sound waves into mechanical vibrations.
  • The inner ear transforms mechanical vibrations into electrical stimuli. 

On the left, a diagram of the ear:         

1: the outer ear

2: the middle ear

3: the inner ear

                       

 

The outer ear

It consists of the pinna (visible part) and the external auditory canal.

The auditory canal extends into the eardrum. Its diameter varies from one person to another. It is a curved duct, which sometimes makes it difficult to explore. It is completely covered with skin and is divided into two parts.

The outer ear is cartilaginous and covered with hair. This is where the wax producing glands are found.

The inner part is bony and completely smooth. No glands are present and the area therefore produces no wax.

Remember

The eardrum (see diagram above) is a fine, semi-transparent, elastic membrane. It is pliable and fragile. Sound waves make it vibrate and the waves are thus transmitted to the ossicles in the middle ear. Another role of the eardrum is to prevent foreign bodies from entering.