Ischemia occurs when blood flow is insufficient to deliver an amount of oxygen and nutrients necessary for maintenance of cell integrity.

Human Physiology/The gastrointestinal system - Wikibooks, open books for an open world

If it is attached to the surface by a narrow elongated stalk it is said to be pedunculated. Several of the enteric hormones are known to enhance rates of proliferation.

Two smooth muscle valves, or sphincters, keep the contents of the stomach contained. Parietal cells secrete hydrochloric acid and intrinsic factor; chief cells secrete pepsinogen; goblet cells secrete mucus; argentaffin cells secrete serotonin and histamine; and G cells secrete the hormone gastrin.

Another method of examination of the stomach, is the use of an endoscope. They can also be caused by viruses or by intestinal parasites like amebiasis and Giardiasis. Paradoxically, NO also contributes to mucosal injury in a number of digestive diseases. The alimentary canal is lined by sheets of epithelial cells that form the defining structure of the mucosa.

The micrographs below depict severe disruption of the barrier. An initially minor effect from ischemia is thus amplified into very significant damage to barrier function. Being more active and increasing daily exercise also helps keep bowel movements regulated. The gallbladder stores bile, which is released when food containing fat enters the digestive tract, stimulating the secretion of cholecystokinin CCK.

Stomach - Wikipedia

It is composed of avascular connective tissue and simple squamous epithelium. The pancreas is composed of pancreatic exocrine cells, whose ducts are arranged in clusters called acini singular acinus.

When in the large intestine, most of the water and salt from the waste products are reabsorbed because they are needed by the body for our everyday functions. The cephalic phase is activated by the smell and taste of food and swallowing.

Human Physiology/The gastrointestinal system

In the digestive system the stomach is involved in the second phase of digestion, following mastication chewing. These hold the anus closed until defecation occurs. A common clinical correlate in many mammals is that use of aspirin and other non-steroidal antiinflammatory drugs NSAIDs which inhibit prostaglandin synthesis is commonly associated with gastric erosions and ulcers. However, lampreys , hagfishes , chimaeras , lungfishes , and some teleost fish have no stomach at all, with the oesophagus opening directly into the anus.

You are at a higher risk to have this disease if you have a close relative who has had it. When you smell or see something that you just have to eat, you start to salivate in anticipation of eating, thus beginning the digestive process.

A Hindi translation of this page was created by Nikol Barton and is available at Hindi translation.

The Gastrointestinal Barrier

Greater curvature 5. The greater omentum hangs from the greater curvature. Here we will be looking at the importance of these two functions of the digestive system: