Human digestive system it is eaten. After two hours the stomach has emptied. In the small intestine, the pH becomes crucial; it needs to be finely balanced in order to activate digestive enzymes. The chyme is very acidic, with a low pH, having been released from the stomach and needs to be made much more alkaline. This is achieved in the duodenum by the addition of bile from the gall bladder combined with the bicarbonate secretions from the pancreatic duct and also from secretions of bicarbonate-rich mucus from duodenal glands known as Brunner's glands. The chyme arrives in the intestines having been released
Development of the digestive system a membranous sac attached to the embryo, which provides nutrients and functions as the circulatory system of the very early embryo. The lateral body wall folds, pulling the amnion in with it so that the amnion surrounds the embryo and extends over the connecting stalk, which becomes the umbilical cord, which connects the fetus with the placenta. If the ventral body wall fails to close, ventral body wall defects can result, such as ectopia cordis, a congenital malformation in which the heart is abnormally located outside the thorax. Another defect is gastroschisis, a congenital defect in the anterior abdominal wall