Question

activity 17: quiz
module: nervous
topic: structures / type: combination

what structure is highlighted?

a. scala vestibuli
b. modiolus
c. scala tympani
d. vestibular membrane
e. spiral ligament of cochlea

Explanation:

Identify the histological section

Using the Cochlea Histology knowledge point
The image shows a cross-section of the cochlea, which is a spiral, bony chamber of the inner ear. The central bony pillar is the modiolus, around which the cochlear canal winds.

Analyze the highlighted compartments

Using the Scala Vestibuli and Scala Tympani knowledge points
Each turn of the cochlear canal is divided into three fluid-filled chambers:

• Scala vestibuli: The upper chamber, located superior to the vestibular membrane.
• Scala media (cochlear duct): The middle, triangular chamber containing the organ of Corti.
• Scala tympani: The lower chamber, located inferior to the basilar membrane.

In the provided histological section, the green highlighted regions correspond to the upper chambers of the cochlear turns. These chambers are located superior to the vestibular membrane and are filled with perilymph. Therefore, the highlighted structure is the scala vestibuli.

Answer:

• A. Scala vestibuli (Correct answer)
• B. Modiolus
• C. Scala tympani
• D. Vestibular membrane
• E. Spiral ligament of cochlea