Fig. 8.

Thin epithelium of the oral ridges, light microscopy (A, B, D, E, and G) and TEM (C and F) images. The goblet cells (go) in the thin epithelium of the oral ridges show different cell shapes depending on the epithelium height. (A) Near the ridge base the cells are round to oval. Scale bar = 10 μm. (B) Close to the ridge top the cells are slender. Scale bar = 10 μm. (C) Granule synthesis occurs in the basal part, supported by several layers of rER and a large Golgi network. Scale bar = 2 μm. (D) The cells are strongly periodate-reactive (PAS staining). Scale bar = 10 μm. (E–G) Secretion process in the goblet cells: as in the columnar cells, the apical part also is pinched off and several granules are released into the gap between the ridges. Scale bars = 10 μm, except in (F) = 2 μm.