Human digestive system teeth, and also by the contractions of peristalsis, and segmentation. Gastric acid, and the production of mucus in the stomach, are essential for the continuation of digestion. Peristalsis is the rhythmic contraction of muscles that begins in the esophagus and continues along the wall of the stomach and the rest of the gastrointestinal tract. This initially results in the production of chyme which when fully broken down in the small intestine is absorbed as chyle into the lymphatic system. Most of the digestion of food takes place in the small intestine. Water and some minerals are reabsorbed back into the
National Institute of Diabetes and Digestive and Kidney Diseases Diseases Data System; National Digestive Diseases Data System; Kidney and Urologic Diseases Research Centers; and Digestive Diseases Research Centers. June 10, 1993—The NIH Revitalization Act of 1993 (P.L. 103—43) established the NIDDK as the lead Institute in nutritional disorders and obesity, including the formation of a research and training centers program on nutritional disorders and obesity. The act also provided for the directors of the National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institute on Aging, National Institute of Dental Research, and the NIDDK to expand and intensify research and related programs concerning osteoporosis, Paget's disease, and related