General Overview of the Digestive System

The digestive system consists of the digestive tract, a tube extending from the mouth to the anus, and its associated accessory organs (primary glands), which secrete fluids into the digestive tract. The digestive tract is also called the alimentary canal. The term gastrointestinal tract technically only refers to the stomach and intestines.

The first section of the digestive tract is the mouth, or oral cavity. It is surrounded by the lips, cheeks, teeth, and palate, and it contains the tongue. The salivary glands and tonsils are accessory organs of the oral cavity. The oral cavity opens posteriorly into the pharynx, which in turn, continues inferiorly into the esophagus. The major accessory structures are single-celled or small, simple tubular mucous glands distributed the length of the pharynx and the esophagus. The esophagus opens inferiorly into the stomach. The stomach wall contains many tubelike glands from which acid and enzymes are released into the stomach and are mixed with ingested food. The stomach opens inferiorly into the small intestine. The first segment of the small intestine is the duodenum. The major accessory structures in the segment of the digestive tract are the liver, the gallbladder and the pancreas. The next segment of the small intestine is the jejunum.

Small glands exist along its length and it is the major site of absorption. The last segment of the small intestine is the ileum, which is similar to the jejunum except the fewer digestive enzymes and more mucus are seceted and less absorption occurs in the ileum. The last section of the digestive tract is the large intestine. Its major accessory glands secrete mucus. It absorbs water and salts and concentrates undigested food into feces. The first segment is the cecum, with the attached vermiform appendix. The cecum is followed by the ascending, tranverse, descending and sigmoid colons and the rectum. The rectum joints the anal canal, which ends at the anus, the inferior termination of the digestive tract.

1. Painful syndrome. Intensive pain, paroxysmal, after the meal, more often at night and on empty stomach. The pain is localized in epigastrium, umbilicus, right subcostal area, sometimes irradiates to waist or has spread character. Tenderness on palpation in pyloroduodenal area, muscular defence, and hyperesthesia of skin in tender zones (zakhariev-Ged), positive sign of Mendel.
2. Dyspeptic syndrome; vomiting, nausea, heartburn, vomiting frequently causes relief, removing pain, decrease of appetite, tendency to constipation (in patients with increased gastric acidity) or unstable stool (in patient with low gastric acidity).
3. Intoxication syndrome; weakness, lucidity, bad sleep, headache, irritability, tearfulness, increased disposition to perspiration, blue shadows under the eyes.