Human digestive system the superior mesenteric artery, which supplies the regions of the digestive tract derived from the midgut, which includes the distal 2/3 of the duodenum, jejunum, ileum, cecum, appendix, ascending colon, and the proximal 2/3 of the transverse colon. The final branch which is important for the digestive system is the inferior mesenteric artery, which supplies the regions of the digestive tract derived from the hindgut, which includes the distal 1/3 of the transverse colon, descending colon, sigmoid colon, rectum, and the anus above the pectinate line. The enteric nervous system consists of some one hundred million neurons that are embedded
Digestive system of gastropods that the anus of the animal is located above its head. A number of species have developed special adaptations to feeding, such as the "drill" of some limpets, or the harpoon of the neogastropod genus "Conus". Filter feeders use the gills, mantle lining, or nets of mucus to trap their prey, which they then pull into the mouth with the radula. The highly modified parasitic genus "Enderoxenos" has no digestive tract at all, and simply absorbs the blood of its host through the body wall. The digestive system usually has the following parts: The buccal mass is the first part