The Illinois state sales tax rate is 6.25%, and the average IL sales tax after local surtaxes is 8.19%. Counties and cities can charge an additional local sales tax of up to 3.5%, for a maximum possible combined sales tax of 9.75%.
(clue: look up Hirschsprung's disease.) The first important step in development of the digestive system occurs during folding of the embryonic disc as neurulation takes place (weeks 4 and 5) - the thin endodermal layer is gathered up' inside the embryonic body to form a tubular structure. Gut tube, respiratory diverticulum, yolk sac, and allantois.
1 The 3 germ layers-the ectoderm, the mesoderm, and the entoderm (endoderm): are in place at the end of gastrulation. The entoderm development is simpler than that of either mesoderm or ectoderm. 2  It is a monocellular layer lining the yolk sac until cephalocaudal flexion of the embryo takes place. 3  Flexion takes the embryo from a flat disk to its basic embryonic body form.