Synonym
Gastrointestinal tract
Definition
The term digestive tract is used to describe an organ system of the human body that is responsible for the absorption, digestion and utilization of food and fluids and is essential for a problem-free life.
Classification of the gastrointestinal tract
The digestive tract of the human body is divided into an upper and a lower digestive tract. Upper digestive tract: the upper digestive tract includes the mouth and throat area through which food and liquid is absorbed. This is where the primary processing of food is performed.
In this process, the food is crushed purely mechanically in the mouth by the teeth and moistened by the salivary glands of the oral cavity. These two mechanisms serve as preparation for the swallowing process. It is important that the food is crushed into small bites.
This is the only way it can pass through the following digestive tract in size. Insalivation serves to make the bites slip better. After the mouth and throat, the food passes through the esophagus.
Through the epiglottis, which closes the windpipe during swallowing, the food is pushed in the right direction into the esophagus. Rhythmic contraction of the muscles of the esophagus ensures that the food is pushed down. After a length of about 50-60 cm, the food reaches the stomach.
Here the mechanical processing of the food ends. From here on, chemical and enzymatic splitting processes occur increasingly. The stomach is a very acidic environment.
This ensures that bacteria, which are present in all food, are killed. The bites are further reduced by muscular kneading movements. The once eaten food bite has become a food pulp in the stomach, which is then passed on to the duodenum.
This is where the so-called lower gastrointestinal tract begins. Lower gastrointestinal tract: The duodenum (duodenum) absorbs the chyme coming from the stomach. Here it is mixed with the bile acids that are produced in the liver and stored in the gallbladder.
This leads to a further splitting of the food. Enzymes for fat splitting (lipase) now also reach the digestive tract via the pancreas and are thus mixed with the food. The duodenum is followed by the small intestine, which in turn is divided into further sections, but these flow into each other.
One still distinguishes the jejenum and the ileum. These sections are traversed by the now almost liquid chyme, some nutrients are extracted from the food here and made accessible to the body cells via the blood. The small intestine system is followed by the large intestine (colon).
One of its main tasks is the detoxification and thickening of the chyme. The removal of water is particularly important because in this way, in addition to the amount of water consumed, the body can also recycle the liquid in the food. As long as the food remains in the large intestine, it becomes thicker and thicker as the water is removed.
Now there are only unusable food components and toxins left in the intestine. All necessary food components have so far been removed from the chyme and returned to the body. A part of the large intestine is called rectum.
The end part of the intestinal system, also known as the rectum, serves as a storage section, which is used to retain the stool prepared for excretion until the quantity and consistency is sufficient to start the defecation. As the amount of stool increases, so does the pressure within the rectum. Certain nerve tracts now trigger the urge to defecate in humans.
With the excretion of the stool, the digestive passage from food intake to excretion ends. From beginning to end, the food has covered a period of 60 to 120 hours. The digestive mechanisms are basically the same in every person, but differ slightly from person to person in terms of stool frequency.
On average, bowel movements are excreted daily or every two days. However, it can also happen that defecation occurs every three days. An increased stool frequency up to a maximum of 3 daily stools is still considered physiological. More frequent bowel movements should be clarified medically, since a metabolic or utilization disorder can always be the reason for this.If no bowel movement has taken place after approximately one week, laxative measures should be taken. Also a possible intestinal obstruction (ileus) should be excluded in this case.