Final answer:
The scala vestibuli and scala tympani are parts of the cochlea involved in hearing; the scala vestibuli extends from the oval window to the cochlea's apex, and the scala tympani extends from the apex to the round window.
Step-by-step explanation:
Within the cochlea are two compartments: The scala vestibuli is the portion of the cochlea that extends from the oval window to the apex of the cochlea. The scala tympani is the portion that extends from the apex of the cochlea to the round window. These fluid-filled compartments are essential for transducing sound vibrations into neural signals, a process that is critical for hearing. The scala vestibuli and scala tympani flank the cochlear duct, which contains the organ of Corti. The organ of Corti is responsible for converting the wave motion of the fluid in both scala into signals that the brain interprets as sound. As the cochlear fluid moves, it stimulates the sensory cells within the organ of Corti that then transduce this mechanical energy into electrical signals sent to the brain.