Final answer:
Both inner and outer hair cells are attached to the basilar membrane and integral in sound transduction in the auditory system. They also play roles in the vestibular system, contributing to balance.
Step-by-step explanation:
The structures attached to the basilar membrane are both inner hair cells and outer hair cells. These hair cells are critical in the auditory system as they are responsible for transduction in the organ of Corti.
Inner hair cells play the primary role in conveying auditory information to the brain, with each inner hair cell synapsing with numerous afferent neurons. Outer hair cells, while fewer in number, are involved in enhancing the precision of sound transduction. Collectively, these cells convert mechanical sound vibrations into neural signals that are transmitted to the brain via the cochlear nerve.
In the vestibular system, hair cells also play a crucial role. They are stimulated by movements such as tilts or accelerations, aiding in the maintenance of balance.