Coloured scanning electron micrograph (SEM) of a freeze-fracture through the jaw of a 14 day old mouse embryo showing the late cap stage of a developing molar tooth. The gums are the thin layer (pink) at top, with fibroblasts (collagen-producing cells) and connective tissue (grey) below them. The dental follicle (yellow) contains pre-odontoblasts (orange) and pre-ameloblasts (red). Ameloblasts are the cells that secrete the enamel that covers the crown (visible part) of the tooth. Odontoblasts create dentine, the mineralised connective tissue that forms the bulk of the tooth. The picture was created as part of a cooperation with Quintessenz Publishing. Magnification: x450 when printed at 15cm wide.