The distribution of filamentous actin and mitochondria in a culture of human embryonic kidney cells (shown above) was visualized with BODIPY FL conjugated to phallacidin and MitoTracker Red CMXRos (pseudocolored yellow). Cell nuclei were counterstained with TO-PRO-3, a carbocyanine monomer with long-wavelength red fluorescence. Images were recorded with a 60x oil immersion objective using a zoom factor of 2.5 and sequential scanning with the 488-nanometer spectral line of an argon-ion laser, the 543-nanometer line from a green helium-neon laser, and the 633-nanometer line of a red helium-neon laser. During the processing stage, individual image channels were pseudocolored with RGB values corresponding to each of the fluorophore emission spectral profiles unless otherwise noted above.