Ear anatomy and physiology
What is the ear?
The ear is the organ of hearing. The parts of the ear include:
External or outer ear, consisting of:
- pinna or auricle - the outside part of the ear
- external auditory canal or tube - the tube that connects the outer ear to the inside or middle ear
- tympanic membrane - also called the eardrum. The tympanic membrane divides the external ear from the middle ear.
Middle ear (tympanic cavity), consisting of:
ossicles - three small bones that are connected and transmit the sound waves to the inner ear. The bones are:
- eustachian tube - a canal that links the middle ear with the throat area. The eustachian tube helps to equalize the pressure between the outer ear and the middle ear. Having the same pressure allows for the proper transfer of sound waves. The eustachian tube is lined with mucous, just like the inside of the nose and throat.
- ossicles - three small bones that are connected and transmit the sound waves to the inner ear. The bones are:
Inner ear, consisting of:
- cochlea (contains the nerves for hearing)
- vestibule (contains receptors for balance)
- semicircular canals (contain receptors for balance)