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.
Tissue Layers of the Digestive Tract. Last Updated: Tuesday, February 7, 2012. Most of the tissue in the digestive tract itself has four layers. These layers are called the mucosa, the submucosa, muscularis externa, and the serosa. The layer in the innermost part of the digestive tract is called the mucosa.The mucosa serves to line the cavity of the tract. The mucosa consists of three sub-layers called the epithelium, the lamina propria, and the muscularis mucosae.issue Layers of the Digestive Tract. Last Updated: Tuesday, February 7, 2012. Most of the tissue in the digestive tract itself has four layers. These layers are called the mucosa, the submucosa, muscularis externa, and the serosa. The layer in the innermost part of the digestive tract is called the mucosa.