Forerunner cells at the end of gastrulation.
80-100% epiboly. Forerunner cells overlapped by the converging germ ring.
Play QuickTime movie of forerunner cells at end of gastrulation:
Vegetal pole view of a 80-100% epiboly embryo. Dorsal is toward the bottom-left corner. Embryo was labeled with BODIPY 505/515. The forerunner cells (arrow in above image) are the wedge shaped mass of cells in the most vegetal position in front of the blastoderm margin on the dorsal side of the embryo. Notice that the forerunner cells are overlapped by cells of the converging germ ring. The forerunner cells are depressed into a more ventral position in the forming tail bud. Soon, Kupffer's vesicle will form with the forerunner cells surrounding it (not shown).last update