Stratified squamous epithelium from the esophagus of the rat. Keratin filaments (tonofilaments, arrows) are sparse, and desmosomes are few (see inset), in the basal cell layer of this tissue. Figures 87 and 88 (inset), both courtesy of Scott McNutt, from Chapter 3 (Junctional Specializations) of 'The Cell, 2nd Ed.' by Don W. Fawcett M.D. A PDF copy of the accompanying chapter is available on the ASCB's BioEDUCATE website.