The culture of FoLu fibroblasts presented in the digital image above was labeled for mitochondria with MitoTracker Red CMXRos and for the cytoskeletal filamentous actin network with Alexa Fluor 488 conjugated to phalloidin, a cyclic peptide derived from the toxic death cap mushroom (Amanita phalloides). In addition, the cells were probed for DNA in the cell nucleus with TO-PRO-3, a monomeric cyanine nucleic acid stain. 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, with the exception of TO-PRO-3, which was pseudocolored cyan.