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
Coupled human–environment system competition" within the "Biocomplexity in the environment" program, and in 2007 gained formal standing. Coupled human–environment system A coupled human–environment system (known also as a coupled human and natural system, or CHANS) characterizes the dynamical two-way interactions between human systems (e.g., economic, social) and natural (e.g., hydrologic, atmospheric, biological, geological) systems. This coupling expresses the idea that the evolution of humans and environmental systems may no longer be treated as individual isolated systems, compared to earlier times in human history when human-environmental interactions were weak and one-way (linear). As CHANS research is relatively new, it has not yet matured into