Question

Given below is a diagrammatic cross section of a single loop of human cochlea:

Which one of the following options correctly represents the names of the different parts?

• A. A: Tectorial membrane, B: Perilymph, C: Secretory hair cells, D: Endolymph
• B. A: Endolymph, B: Secretory hair cells, C: Serum, D: Tectorial membrane
• C. A: Secretory hair cells, B: Endolymph, C: Tectorial membrane, D: Perilymph
• D. A: Perilymph, B: Tectorial membrane, C: Endolymph, D: Organ of Corti

Answer 1

The correct option is D A: Perilymph, B: Tectorial membrane, C: Endolymph, D: Organ of Corti

Cochlea is the main hearing organ, where sound waves are transformed into electrical impulses which are sent on to the brain.
It consists of three fluid-filled chambers or canals, the upper scala vestibuli, lower scala tympani and middle scala media.
Both scala vestibuli and scala tympani are filled with perilymph, while scala media is filled with endolymph. The tectorial membrane overhangs the sensory hair in scala media.