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.
The chorion, the amnion, the yolk sac, and the allantois constitute the fetal membranes. They develop from the zygote but do not participate in the formation of the embryo or fetusexcept for parts of the yolk sac and allantois. Part of the yolk sac is incorporated into the embryo as the primordium of the gut.