Question

module: nervous
topic: structures / type: combination

what structure is highlighted?

a. scala vestibuli
b. cochlear duct
c. vestibular membrane
d. scala tympani
e. basilar membrane

attempt: 1/1

Explanation:

Identify the histological section

Using the Cochlea Histology knowledge point
The image shows a cross-section of the bony cochlea, which spirals around a central bony axis called the modiolus. Each turn of the cochlea contains three fluid-filled chambers: the scala vestibuli, the cochlear duct (scala media), and the scala tympani.

Analyze the highlighted regions

Using the Scala Tympani knowledge point
The green highlighted regions are located in the lower chamber of each cochlear turn. In standard cross-sections of the cochlea, the scala vestibuli is the upper chamber (separated from the cochlear duct by the vestibular membrane), the cochlear duct is the middle triangular chamber, and the scala tympani is the lower chamber (separated from the cochlear duct by the basilar membrane). The highlighted spaces are situated below the basilar membrane and spiral organ, identifying them as the scala tympani.

Answer:

• (A) Scala vestibuli
• (B) Cochlear duct
• (C) Vestibular membrane
• (D) Scala tympani (Correct answer)
• (E) Basilar membrane