Cochlea cells. Scanning electron micrograph (SEM) of a vertical section through part of the cochlea inside a human ear. The section shows part of the row of columnar outer pillar cells that runs along the organ of Corti, the auditory sense organ. The outer pillar cells arise from the basilar membrane (across bottom), and their upper surfaces (across top) form part of the surface of the organ of Corti. This organ lies on the basilar membrane, an internal surface of the cochlear duct. The organ of Corti also contains hair cells (not seen) and an overlying tectorial membrane (removed). Sound waves deform hair cell cilia and trigger auditory nerve impulses. Magnification: x600 at 6x7cm size.