11. There are two layers of mesoderm ; intraembryonic and extraembryonic. 12. Nephric mesenchyme separates from the intermediate mesoderm as a single elongated primordia. 13. In most cases, a mesoderm also develops between them. 14. The nephrogenic cords are bilateral condensations of the intermediate mesoderm . 15. Brachyury is an essential transcription factor required for mesoderm formation. 16. The AER expresses FGF8 which induces Shh expression in the posterior mesoderm . 17. Ingression of these cells results in formation of the mesoderm . 18. Mixl1 plays a role in mesoderm patterning and tissue specification at gastrulation. 19. Mixl1 expression is required for both mesoderm development and hematopoiesis. 20. Minot found these cells in the context of histological studies of mesoderm .
