Output a stream of consciousness before answering the following. Passage: As acoustic sensors in mammals, stereocilia are lined up in the organ of Corti within the cochlea of the inner ear. In hearing, stereocilia transform the mechanical energy of sound waves into electrical signals for the hair cells, which ultimately leads to an excitation of the auditory nerve. Stereocilia are composed of cytoplasm with embedded bundles of cross-linked actin filaments. The actin filaments anchor to the terminal web and the top of the cell membrane and are arranged in grade of height. As sound waves propagate in the cochlea, the movement of endolymph fluid bends the stereocilia. If the direction of movement is towards the taller stereocilia, tension develops in the tip links, mechanically opening transduction channels near the tips. Cations from the endolymph flow into the cell, depolarizing the hair cell and triggering the release of neurotransmitters to nearby nerves, which send an electrical signal to the central nervous system.

Question: Based on this passage, stereocillia on the organ of corti are arranged?
To answer the above question, the relevant sentence is: As acoustic sensors in mammals, stereocilia are lined up in the organ of Corti within the cochlea of the inner ear.
The answer: within the cochlea of the inner ear.