Fig. 3. Incubating fixed pseudobranch cells with FITC-labeled streptavidin resulted in a photostable staining of mitochondria. The confocal image shows three optical sections of a pseudobranch cell in the x,z (A), x,y (B) and y,z (C) planes. Within each image the locations of the two accompanying sections are indicated by white cross-sectional bars, i.e. in the x,y section (bottom left) the horizontal bar indicates the location of the x,z section (top image), and the vertical bar the location of the y,z section (bottom right). A similar picture was obtained by in vivo staining using the mitochondria-selective dyes Mitotracker green FM and Mitotracker orange. Scale bar, 10 µm.