Which part of the vestibular apparatus is influenced by changes in gravity and linear acceleration?

The correct choice is related to how the sacculus and utriculus are integral components of the vestibular apparatus, specifically designed to detect changes in gravity and linear acceleration. These structures contain hair cells embedded in a gel-like substance that also holds tiny calcium carbonate crystals known as otoliths. When the body experiences changes in position or movement related to gravity, the otoliths shift due to their inertia, which in turn displaces the hair cells. This displacement generates a neural signal that is interpreted by the brain, allowing it to maintain balance and spatial orientation during linear motions.

In contrast, the cochlea is primarily responsible for hearing, converting sound vibrations into neural signals. The semicircular canals detect rotational movements rather than changes in gravity or linear acceleration. While otolith organs refer to the collective function of the sacculus and utriculus, the term specifically pointing to the sacculus and utriculus as the elements of the vestibular system that respond to gravity and linear acceleration emphasizes their unique role in maintaining balance and orientation.