Pinna
Soft cartilaginous outer portion of the ear
- Allows sounds to be collected
Acoustic Meatus
- The canal of the ear that carries the sound waves to the eardrum
- Lined with hair
- Covered with cerumen
Cerumen
- A waxy substance that traps dust particles
- Lines the acoustic meatus
Tympanic Membrane (Eardrum)
- A resistant elastic membrane at the end of the acoustic meatus
- Vibrates when it receives sound waves from the canal, and then transmits the waves to the ossicles
Tympanic Cavity
- A small cavity surrounding the bones of the middle ear
Malleus
- Hammer-shaped ossicle/bone in the middle ear
- Connected to eardrum, and lateral to the incus bone
Incus
- Anvil-shaped small ossicle/bone in middle ear
- Connects the malleus bone to the stapes bone
Stapes
- Stirrup-shaped small ossicle/bone in the middle ear
- It is the smallest and lightest bone in the human body
Semicircular Canals
- Three interconnected tubes
- Located inside each ear
Vestibule
- A bony structure into which the three semicircular canals opens into
- With these canals, it is responsible for equilibrium
Cochlea
- Bony structure intended for hearing
- Part of the inner ear
- It receives vibrations from the ossicles, and transforms them into nervous impulses before transmitting them to the brain
Vestibular Nerve
- Nerve transmitting messages related to equilibrium to the brain
- Emanates from both the vestibule and semicircular canals
The Ear
- the organ of hearing and equilibrium
- Organized into the External, Middle, and Inner Ears
Auricle
- A visual outer portion of the ear enabling sounds to be collected
- Consists of : The auricle, external acoustic meatus, and the tympanic membrane
- Leads into the middle ear
Auditory (Eustachisan) Tube
- Tube connecting the middle ear to the nasopharynx
- Equalizes air pressure on both sides of the eardrum
Cochlear Nerve
- Transmits auditory messages collected in the cochlea to the brain
- Joins with the vestibular nerves to form the auditory nerve
- Extends to the brainstem, where its fibers make contact with the cochlear nucleus
The Internal Ear
- Liquid-filled cavity hollowed out of the temporal bone
- Transforms sound vibrations into nerve influxes to be interpreted by the brain
The Middle Ear
- Air-filled cavity hollowed out of the temporal bone
- Receives sound from the external ear, amplifies them, and transmits them to the internal ear
The External Ear
- The visible portion of the ear
- Enables sounds to be collected and directed to the middle ear through the acoustic meatus
