Ear Anatomy

hearing

balance

What are the two main functions of the ear?

external ear, middle ear, inner ear

What are the three subdivisions of the ear?

auricle or pinna

external acoustic meatus

What are the two main parts of the external ear

auricle or pinna

The part of the ear that "sticks out of the head" is called:

External acoustic meatus

What part of the external ear begins at where the rolled up part of the auricular cartilage narrows and ends at the eardrum?

earwax

What does the gland in the skin lining the external acoustic meatus produce to prevent dust from reaching the eardrum

tympanic

The middle ear is essentially formed by what cavity:

auditory tube or Eustachian tube

The tympanic cavity communicates with the nasopharynx via the:

eardrum or tympanic membrane

Incorporated into the lateral aspect of the tympanic cavity is the :

auditory ossicles

These three small bones transmit sound waves across the tympanic cavity:

auditory ossicles

These three small bones transmit sound waves across the tympanic cavity:

middle

The tympanic cavity, auditory ossicles and the tympanic membrane would be part of what subdivision of the ear?

cochlea

Hearing based on mechanical stimuli produced by sound waves are transformed into nerve impulses in the ____________ of the inner ear.

vestibule

BALANCE can be detected based on the action of small amounts of fluid on neuroreceptors within the __________ of the inner ear

internal acoustic meatus

The inner ear is exposed to sound vibrations on its lateral surface. These are converted into impulses that leave on nerve fibers through the __________________on the medial surface.

membranous labyrinth

The inner ear consists of the complex, closed system of tiny membranous ducts and cavities called the ______________.

concha

ID the general area of the external ear outlined and labeled "B"

scapha

ID the general area of the external ear outlined and labeled "A"

Apex

ID #1

medial border of the helix

ID #2

antihelix

3?

pretragic incisure

4?

tragus

5?

intertragic incisure

6?

antitragus

7?

lateral border of the helix

8?

ear canal

The external acoustic meatus is also called the:____________

Disadvantages include drainage of material from the ear canal problematic. In breeds with dependent ear forms and relatively large amounts of hair in the ear canal, chronic otitis externa can develop. Otitis externa is a chronic inflammation of a dog external ear canal.

You should know why the "L" shape of the ear canal can be disadvantageous.

Otitis Externa

Chronic inflammation of a dog external ear canal is called:

Also callled Swimmer's Ear

1-Pinna

2-External acoustic meatus

3-Tympanic membrane

4-Auditory ossicles

5-Vestibule fluid of inner ear

6-Vestibulocochlear nerve

7-Brain

You tell your dog to "sit". Enter the terms in the correct order for your command to reach your dogs brain.

tympanic bulla

Identify the structure indicated by "x"

external acoustic meatus

The opening, indicated by "z", is for what "structure"

eardrum or tympanic membrane

The opening, indicated by "z", is covered in life by what structure?