We analyze the structure of a small sample of galaxies, using a set of CCD images in standard photometric bands presented in a previous paper (Prieto et al. 1991). These and their combinations in the form of color index images, offer high quality information about the structure of the galaxies, allowing us to pick out the major concentrations of dust and star formation, notably in the intermediate zone between bulge and disk. The detection of these structures allows us to interpret the radial luminosity profiles of the galaxies, in particular where these show departures from the simple sum of an R exp 1/4 law bulge component and an exponential disk component. The radial color index profiles are shown to be especially useful in revealing the presence of a true bulge and hence in effecting a reliable bulge-disk decomposition. We infer that in all the galaxies examined here, the causes of observed departures from simple two-component bulge + disk models for radial profiles are to be found in the intermediate zones of the galaxies, and are the enhanced young stellar populations and the associated dust concentrations encountered in these zones.