Question

Given above is a diagrammatic cross section of a single loop of human cochlea. Which one of the following options correctly represents the names of three different parts?

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

Answer 1

The correct option is B A: Perilymph, B: Tectorial membrane, C: Endolymph, D: Sensory hair cells

The inner ear contains the sensory apparatus. It consists of a bony shell (the bony labyrinth) within which is found the membranous labyrinth, series of cavities forming a closed system filled with endolymph, a potassium-rich liquid. The membranous labyrinth is separated from the bony labyrinth by the perilymph, a sodium-rich liquid.

The tectorial membrane (TM) is an extracellular connective tissue, that covers the mechanically sensitive hair bundles of the sensory receptor cells in the inner ear. Arranged on the surface of the basilar membrane are orderly rows of the sensory hair cells, which generate nerve impulses in response to sound vibrations. Together with their supporting cells, they form a complex neuroepithelium called as the basilar papilla or organ of Corti.