Final answer:
The cochlear duct's roof is known as the vestibular membrane, separating it from the scala vestibuli. Its floor is made up of the basilar membrane, with the organ of Corti housing the hair cells for sound transduction.
Step-by-step explanation:
The correct option : c
The cochlear duct, positioned within the cochlea of the inner ear, is an essential component for hearing. It sits between two fluid-filled cavities, the scala vestibuli and scala tympani. The vestibular membrane, also known as Reissner's membrane, forms the roof of the cochlear duct and separates it from the scala vestibuli. Below the cochlear duct lies the basilar membrane, which supports the organs of Corti, containing sensory hair cells that transmit auditory signals when they vibrate in response to sound.
The tectorial membrane is another important structure, situated above the hair cells of the organ of Corti, which plays a part in the transduction of sound waves into neural signals. The vibrations in the cochlear fluid resulting from sound waves move the basilar membrane at different spots, corresponding to the frequency of these waves. This movement in turn affects the hair cells and leads to the creation of neural signals that the brain interprets as sound.