We explain what the digestive system is and its functions. Organs that constitute it, and common diseases of the digestive system.
What is the digestive system?
The digestive system or digestive system is known as the set of organs and ducts that are involved when it comes to feeding and absorbing the nutrients acquired, both in the body of the human being and in that of many animals superior.
Digestion is the name that receives this process, in which food is transformed and energy and nutrients essential for the support and development of life are obtained from them . This implies the reduction of the organic matter consumed to its most usable elementary parts, and the expulsion of the remaining material from the organism.
The digestive system, in charge of it, includes the entire process from the entry of food into the mouth, until the expulsion of feces, through the absorption of nutrients. It is a complex mechanism, which involves many parts of the body and is essential for life, since animals get energy from the oxidation of glucose, a sugar that It can only be obtained by reducing the organic matter we eat.
See also: Circulatory System.
Functions of the digestive system
The digestive system fulfills various functions, which are transport, secretion, absorption and excretion .
- Transportation Food is taken from the mouth, where it is crushed and converted through saliva into a bolus of food, to the stomach, then the intestines and finally to the outside of the body, through a series of ducts endowed with own muscular movement, peristaltic movement.
- Secretion Once contained in the stomach, the crushed food is subjected to the action of the gastric juices segregated therein, which dissolve the matter and reduce it to its minimum chemical elements.
- Absorption The simple forms extracted from matter, its proteins, amino acids, sugars, etc., are reduced to the minimum possible and are incorporated into the body, then passing into the blood and the body.
- Excretion Once the nutrients are extracted from the food, it is necessary to expel the waste material out of the body, and this is done every so often, through the end of the digestive tract, which in total, from the mouth to the anus, measures about eleven meters
Organs of the digestive system
The digestive system comprises the following organs of the human body:
- Mouth and salivary glands . The beginning of the process is located at the entrance of the food to the mouth, where the teeth serve to grind it and the saliva produced by the salivary glands moistens it.
- Esophagus It is the conduit that carries food from the mouth to the stomach, through the neck, chest and abdomen, and through a hole in the diaphragm.
- Stomach In this organ the food accumulates, waiting for the secretion of gastric juices and digestive enzymes, by the cells that compose it. These juices are basically hydrochloric acid (HCl).
- Pancreas This gland is in contact with the intestine and pours into the duodenum its pancreatic juice, essential for digestion, and at the same time it spills insulin into the blood to process the sugar that enters the blood through the intestine.
- Liver and gallbladder . The largest viscera of the body (weighs a kilo and a half) is the liver; It secretes bile, which is a substance necessary for fat absorption. Bile accumulates in the gallbladder and from there passes into the duodenum.
- Small intestine From the duodenum to the ileocecal valve, this first portion of the intestine is full of villi and is where the absorption of nutrients occurs. It measures between 6 and 7 meters in length.
- Large intestine The rest of the intestine, which culminates in the rectum, measures between 120 and 160 cm. in length and is where the digestion ends and feces are formed.
- Year . The anal opening is where the food already digested is expelled out of the human body, by controlled movements of the anal sphincter.
Diseases of the digestive system
Diseases of the digestive system are usually of the following types:
- Infections Product of the entry into the intestine of bacteria or viruses, coming from water or contaminated food. They can cause diarrhea, bloody stools or rectal mucus, as well as severe intestinal pain.
- Parasites . Intestinal parasites are frequent in rural populations or in poverty, and are transmitted through contaminated food or water. Many of them can then migrate to other regions of the body and perpetuate the cycle if there is no proper elimination of feces.
- Indigestion Foods in poor condition or contaminated with toxic or harmful substances, generate an intestinal reaction very similar to allergic reactions, with colic and usually diarrhea.
- Gastritis and ulcers . The action of gastric juices and the constant consumption of irritants (alcohol, cigarettes, citrus, etc.) can lead to redness and inflammation of the stomach mucosa (gastritis) and, in more severe cases, ulcers and internal sores.
- Cancer The color of the duodenum, colon, liver or pancreas are known and aggressive forms of malignant tumors, associated with certain feeding habits.