The Stomach Essay, Research Paper
The Stomach
Outline:
The stomach is the organ which digests the food in humans and most animals. some animals, though, have two divisions in digesting foods like birds and ruminants. A ruminant is an even toed animal which regurgitates and masticates its food after swallowing. Their stomach has three chambers, and some of the animals are cattle, goat, deer, antelope, and giraffe, which have four stomach chambers. The outer surface of the stomach is smooth, and the inside is a crumbled up layer covered with mucus. these folds help in the mixing up of food with digestive juices. They then move the material/food into the intestines. A known fact of the stomach is that only water, alcohol, and other kinds of specific drugs can be absorbed from the stomach. Most of the food absorption is taking place in the small intestine.
Location and Path of Food:
The stomach is located on the left side of the body under the diaphragm. The diaphragm is the partition of muscles and tendons between the chest cavity and the abdominal cavity. The esophagus located to the top right of the stomach, serves as an elevator for food. An estimated time for the food to get from the mouth, through the esophagus, to the stomach is seven seconds. A good way to time the food, is to drink something hot if your cold or something cold when your hot. You will be able to feel the change in temperature inside your stomach. After the food enters the stomach’s top, it slowly or quickly moves down the stomach’s fold’s and curves, while the stomach is contracting. It ends at the duodenum after passing the pylorus.
The Layers:
The outer layer surrounding the digestive organ is called the mucous membrane. The inside is called a muscular wall. The muscular wall is laytered or arranged in diagonal, horizontal, vertical, and circular ditches. Where the esophagus and stomach meet, the ditches are larger, and form what is now known as the cardiac sphincter. When contracting or closing up this muscle, you prevent the passage of food into the stomach and food to come out of the stomach (throwing-up). The inner-most layer is called the mucosa, it contains secretory cells. The tissues of the stomach are digestible by gastric juice, and so is mucus. When the body is at normal conditions, the mucus lining the inside of the stomach’s muscular wall, is more rapidly renewed than it is removed. When a psychosomatic condition, or physical disorder to the body, due to emotional distress, prevents correct secretion of mucus gastric mucosa becomes worn out, an ulcer forms. If the ulcer is not tended, it may drill the gastric wall and make a passage, allowing the stomach contents to get out into the abdominal cavity. This will cause peritonitis, the inflammation of the peritoneum. Which is the transparent watery membrane lining the abdominal cavity.
Secretory Cells and Enzymes:
One of the secretory cells secretes hydrochloric acid. It controls the gastric contents distinctly and activates the gastric digestive juices, these juices are digested by another cell. Enzymes found in gastric juices are pepsin. “Pepsin is a digestive enzyme in the gastric juice of stomach secretions.” In the presence of acid, pepsin splits proteins to peptones, or smaller, more absorptive peptides. Another enzyme called rennin, makes milk sour, or “curdles” it, and another enzyme called lipase, splits fats into fatty acids and glycerol. Another type of secretory cell, secretes mucus for the protection of the stomach from its own products.
Digestion:
Meat extracts, cooked grains, and partially digested products of proteins generate the flow of gastric juice. These ingredients are called secretagogues. They form the hormone gastrin in the pyloric end of the stomach. “When gastrin is absorbed it stimulates the secretory glands.” Gastric secretion may also be stimulated by the sight or the smell of food, this reaction is called cephalic or reflex stimulation. When the stomach is empty the walls of the stomach are together. When food enters the stomach, the walls open and the cavity gets bigger. The part of the stomach connected to the esophagus, or the cardiac portion of the stomach, stores the ingested food. First come “waves” of relaxation for the stomachs muscular wall, then the circular muscle contracts. This is called peristalsis. This starts in the middle of the stomach and make the food travel downward and it stops just before arriving at the pyloric canal. The “waves” of relaxationa dn contraction may occur at a rate of “three per minute” they then soften the food and thoroughly mix it with gastric juice.
The movement of food from the stomach to the duodenum is caused by the contraction of the muscular wall. They cause the sphincter to open between the stomach and the duodenum. The self continuation of trying to open the sphincter yourself, leads to a several day paralysis. “The stomach, like the heart, must be regarded as an automatic organ.” As of now it is unknown where the “automaticity” is controlled, either in the “musculature or in an intrinsic nerve mechanism.”
Pain:
Contractions of the empty stomach is known to cause hunger pains in humans. Diseases of the stomach might be caused by psychosomatic problems. The abnormal and painful stomach conditions include ulcers, cancer, dyspepsia/gastric indigestion, and catarrh. Catarrh is the increased flow of mucus in the stomach, it is associated with the inflammation of the mucous membrane. Stomach disorders are best treated by allowing the organ to rest. A one or two day fast, followed by a mild diet, “with gradual additions until the normal diet is restored.”