Cochlea - Osseous part Flashcards
1
Q
Function and description the cochlea
A
- Responsible for mediating the sense of sound
- Resembles a snail shell
- Has about 2 5/8 turns
- Turns are smaller at the apex than at the base
2
Q
The cochlea is made up of 2 main parts. What are they?
A
- Osseous Cochlea
- Membranous Cochlea
3
Q
List the structures (including openings) of the osseous cochlea.
A
- Modiolus
- Osseous spiral lamina
- Oval window
- Round window
- Internal auditory meatus (bony canal)
4
Q
What is the modiolus, and what does it do?
A
- Bony core of the cochlea
- Accommodates nerve fibers from the hair cells, as well as blood vessels
5
Q
Describe the Osseous spiral lamina.
A
- Shelf-like structure that winds around the modiolus from base to apex
- Spiral lamina is narrower at the apex than at the base of the cochlea
- Composed of two thin plates
6
Q
What is between the two thin plates of the osseous spiral lamina?
What is formed?
A
- Between the plates, auditory nerve fibers pass from the hair cells into the cochlea to the spiral ganglion
- to form the auditory nerve
7
Q
The osseous spiral lamina forms the point of attachment for what?
A
- Forms the point of attachment for the Scala media (cochlear duct)
8
Q
The osseous spiral lamina divides the labyrinth into two incomplete chambers. What are they?
A
- Superior: Scala vestibuli (vestibular canal)
- Inferior: Scala tympani (tympanic canal)
9
Q
What is the oval window?
A
- The opening into the scala vestibuli to which the footplate of the stapes is attached
10
Q
What is the round window?
A
- Membrane-covered window between the scala tympani of the inner ear and the middle ear space
11
Q
What does the internal auditory meatus (bony canal) house?
A
- Houses facial, auditory and vestibular nerves, and basilar artery
- Carries these nerve bundles through the temporal bone to the brainstem
