Final answer:
The cochlear duct supports the organ of Corti, containing sensory hair cells and associated with the vestibulocochlear nerve (VIII), crucial for hearing.
Step-by-step explanation:
The cochlear duct, filled with endolymph, supports the organ of Corti which contains the receptors for hearing- the sensory hair cells and nerve endings of the cochlear nerve a division of the vestibulocochlear nerve (VIII).
The organ of Corti is essential for the process of hearing as it is the site of sound transduction. It resides in the cochlear duct space within the auditory portion of the inner ear, flanked by the scala tympani and scala vestibuli on either side. This organ contains the mechanoreceptor hair cells, which send signals to the brain when the stereocilia (hair-like structures) are bent by the movement of fluid in the cochlea caused by sound vibrations. There are two types of hair cells: inner hair cells, which act as the primary auditory receptors, and outer hair cells, which enhance the precision of sound transduction.
The vestibulocochlear nerve, also known as cranial nerve VIII, transmits both equilibrium and auditory sensations from the inner ear to the brain stem. Specifically, the cochlear nerve is a part of this system, which collects and carries auditory information from the cochlea's hair cells to the brain to be interpreted as sound.