Ear Flashcards
What type of epithelium makes up the inner surface of the tympanic membrane?
Simple squamous to simple cuboidal
What kind of epithelium lines the middle ear?
Simple squamous
What is the function of the tensor tympani?
Increase tension on the tympanic membrane
What is the function of the stapedius?
Dampens movement of the stapes on the oval window
What is the attenuation reflex?
Combined action of stapedius and tensor tympani to protect internal ear from damaging loud sounds
What is otosclerosis?
Bone remodeling causing stapes to be fixed onto oval window
What type of epithelium lines the auditory tube?
Pseudostratified columnar with goblet cells
What type of epithelium lines the mastoid air cells?
Simple squamous
What is the endolymphatic space?
Within membranous labyrinth
What is the chemical composition of endolymph?
High K+, low Na+
Where is the perilymphatic space?
Between membranous and bony labyrinths
What is the chemical composition of the perilymphatic space
High Na+, low K+
Where is the cortilymphatic space located?
Within the tunnels of the organ of Corti of the cochlea
What is the chemical composition of the cortilymphatic space?
High Na+, low k+
What are the two divisions of bony labyrinth?
- Cochlear labyrinth2. Vestibular labyrinth
How is the cochlear duct connected to the saccule?
Ductus reuniens
How are the utricle and saccule connected?
Utriculosaccular duct
What is the crista ampullaris?
Sensory receptor located in the ampulla of semicircular duct; for angular movements of the head
What are otoliths?
Crystalline bodies of calcium carbonate and a protein that are specialized to sense linear movement of head and gravity
What is the scala media?
Aka cochlear duct; compartment that houses organ of Corti and ends at helicotrema
What is the scala media filled with?
Endolymph
What is the scala vestibuli?
Compartment above the cochlear duct
What is the scala vestibuli filled with?
Perilymph
What is the scala tympani?
Compartment below the cochlear duct and ends at round window on medial wall of middle ear
What is the scala tympani filled with?
Perilymph
What is the vestibular (Reissner’s) membrane?
- Separates cochlear duct from scala vestibuli (roof of scala media)2. Two layers of squamous epithelium with tight junctions
What fluid does the stria vascularis produce?
Endolymph
What is the basilar membrane?
Forms the floor of the scala media, extends from spiral lamina of modiolus to lateral wall
What is the function of the basilar membrane?
Supports organ of Corti via spiral ligament
Does the organ of Corti have kinocilium?
No
Discrimination between sound frequencies depends on response of what membrane?
Basilar
What can cause increased pressure of endolymph?
- Meniere’s disease2. Dizziness3. Tinnitus4. Vertigo
Where is the spiral ganglion located?
Modiolus
What type of epithelium lines the ossicle?
Simple squamous
In which plane is the utricle?
Horizontal
In which plane is the saccule?
Verticle
What are phalangeal cells?
Support hair cells; inner phalangeal cells completely surround inner hair cells
What is the tectorial membrane?
- Membrane that projects over and attaches to organ of Corti by stereocilia of hair cells2. Made of collagen II, V, IX3. Contains glycoproteins called otogelin and tectorin4. Attached medially at modiolus
