Within just one day the fertilized
egg develops from a single cell into a complete and autonomous organism
consisting of many different organs.
At the blastoderm stage, the 6000 cells giving rise to all somatic tissues are located as a single cell wide epithelium at the surface of the embryo. Cell lineage analyses have shown, that the three germ layers ectoderm, endoderm and mesoderm are already determined at this stage. Thus, a so-called "anlagenplan" or fate map can be pojected onto the embryo.
Germ layers (1.2 MB)
Germ layers, interactive (3.2 MB)