Fig. 9
From: The growth pattern of the human intestine and its mesentery
The ileum assumes its right-sided position only after the umbilical herniation is completely resolved at 10 weeks development. Right-sided (panels a1-c1), left-sided (panels a2-c2) views and caudal views (panels a3-c3) of schematic representations of reconstructions of 9.0 week (s89; top row), 9.5 week (s57; middle row), and 10 week (s1507; bottom row) embryos. The ovals indicate the umbilical orifice. The loops of the 4th secondary loop (blue) and the appendix are still inside the hernial sac at 9 weeks, occupy an intra-abdominal position close to the hernial rim at 9.5 weeks, and have attained their definitive positions (cecum and appendix at L4) at 10 weeks. The appendix is hidden behind the liver in panels b and c, and is indicated with a gray dashed line. L: left; R: right. The scale bars (units in μm) show the diameter of the intestines with their surrounding mesenchyme in that panel. Interactive 3D-PDFs are available online (3D-PDF 9.0WKS and 9.5 WKS)