Question

module: nervous
topic: structures / type: combination

what structure is highlighted?

a. scala vestibuli
b. stria vascularis
c. vestibular membrane
d. spiral organ
e. basilar membrane

Explanation:

Identify the histological section

The image shows a cross-section of the cochlea of the inner ear, displaying multiple turns of the cochlear duct (scala media), scala vestibuli, and scala tympani.

Analyze the highlighted structure

Using the Cochlea Histology knowledge point, we observe a thin, highlighted line (colored green/yellow) separating the upper chamber from the middle chamber.

Identify the specific chambers and membranes

Using the Scala Vestibuli knowledge point:

• The upper chamber is the scala vestibuli.
• The middle chamber is the cochlear duct (scala media).
• The thin membrane separating the scala vestibuli from the cochlear duct is the vestibular membrane (also known as Reissner's membrane).
• The highlighted line corresponds directly to this boundary.

Match with the options

The highlighted structure is the vestibular membrane, which corresponds to option C.

Answer:

• (A) Scala vestibuli
• (B) Stria vascularis</mcq-correct>
• (C) Vestibular membrane (Correct answer)

<mcq-option>(D) Spiral organ

• (E) Basilar membrane