Ear Flashcards
What are the two functions of the ear?
- Maintain balance
2. Perceive sound
The auricle, external acoustic meatus, and tympanic membrane are all part of the _________ ear.
External
The ear ossicles, malleus, incus, and stapes are all part of the _______ ear.
Middle
The epitympanic recess is _______ to the tympanic membrane.
Superior
What structure exits the middle ear cavity anteriorly?
Auditory (Eustachian) tube
What is found at the posterior of the middle ear cavity?
Aditus ad antrum
What types of tissue make up which parts of the auditory tube?
Posterior 1/3 = bony
Anterior 2/3 = cartilage
The _______ _______ makes up the superior wall of the middle ear.
Tegmen Tympani
The _______ _____ makes up the inferior floor of the middle ear.
Jugular wall
Lateral wall of middle ear?
Tympanic membrane
The ______ is a protuberance on the medial wall of the middle ear.
Promontory
What is the fenestra vestibuli also called?
Oval Window
What is the other name for the fenestra cochlea?
Round window
The ________ ________ is a hollow projection of bone on the posterior wall of the middle ear cavity.
Pyramidal eminence
What opening in the posterior wall of the middle ear leads to the mastoid air cells?
Aditus ad antrum
What are the two muscles found in the middle ear?
- Tensor tympani
2. Stapedius
What is the function of the middle ear muscles?
- Reduce oscillations
2. Protects inner ear from loud noise
T/F: The tensor tympani is found in the bony semicanal located superior to the auditory tube.
T
Where does the tensor tymani insert?
Handle of malleus
What nerve innervates tensor tympani?
V3
What is the smallest striated muscle in the body?
Stapedius
Where does the stapedius arise and insert?
Pyramidal eminence -> neck of stapes
What nerve innervates the stapedius?
CN VII
The ______ branches supply blood to the middle ear via the _______ branches.
Tympanic; carotid
Where does the veinous drainage of the middle ear go?
- Superior petrosal sinus
2. Pterygoid plexus
Which cranial nerve goes through the middle ear cavity?
CN VII & chorda tympani
The _______ plexus covers the promontory in the middle ear.
tympanic
What cranial nerve forms the tympanic plexus?
CN IX
What p-symp. nerve comes off of the tympanic plexus to supply the parotid gland?
Lesser petrosal nerve
What is the function of the semicircular canals?
Control balance and position
What is the function of the cochlea?
Control hearing
What structure begins in the oval window?
Cochlea
What marks the end of the cochlea?
Round window
Describe the order of bony connections from the tympanic membrane to the oval window.
Tympanic membrane -> malleus -> incus -> stapes -> oval window
What structures do sound waves travel through after the oval window?
Scala vestibuli -> Helicotrema -> Scala tympani -> Round window
