The opossum kidney cell appearing in the digital image above is in the early anaphase stage of mitosis, the chromosomes appearing to have just become completely separated. The chromosomes were visualized by treating the culture that this cell was resident in with mouse anti-histone (pan) monoclonal antibodies, followed by secondary goat anti-mouse antibodies conjugated to Texas Red. The specimen was simultaneously labeled for peroxisomes with Oregon Green 488 conjugated to goat secondary antibodies that target rabbit anti-PMP 70 (peroxisomal membrane protein 70). Images were recorded with a 60x oil immersion objective using a zoom factor of 5.0 and sequential scanning with the 488-nanometer spectral line of an argon-ion laser and the 543-nanometer line from a green helium-neon laser. During the processing stage, individual image channels were pseudocolored with RGB values corresponding to each of the fluorophore emission spectral profiles.