Final answer:
The statement is false as the basilar membrane does not move in unison; different regions vibrate at different frequencies, selectively stimulating hair cells along the membrane and contributing to pitch resolution.
Step-by-step explanation:
The statement that 'when the mechanical energy of a sound reaches the cochlea, both ends of the basilar membrane move in unison to stimulate both the inner and outer hair cells at the same time' is false. In reality, when sound waves produce fluid waves inside the cochlea, the basilar membrane flexes in a region-specific manner, according to the frequency of the sound waves. High frequency sounds tend to vibrate the membrane near the base (close to the oval window), while lower frequencies travel farther along the membrane before causing appreciable excitation. This differential movement leads to specific hair cells being stimulated at different locations along the basilar membrane, rather than all hair cells being stimulated uniformly at once.
The place theory of hearing explains that the pitch-determining mechanism is based on the location along the membrane where the hair cells are stimulated. The mechanism contributes to the highly refined pitch sensitivity of the human ear, suggesting that an auditory "sharpening" mechanism enhances pitch resolution.