The digestive system is the basis for the uninterrupted operation of the entire human body
The digestive system provideshuman life through the delivery of the necessary nutrients used as a source of energy and building material. These substances enter the body due to the digestive tract, the total length of which is about 10 meters and has throughout the expansion, cavity and constriction.
The structure of the human digestive system includes: the oral cavity, pharynx, esophagus, stomach, pancreas, liver, gall bladder, thick and small intestine.
Oral cavity. In this part of the digestive system, food is directly tested, and its chemical and physical effects are exerted. Chewing food refers to the second type of impact, and from this initial stage of the system depends the quality of intake and assimilation of nutrients. No wonder, many experts advise how to thoroughly chew food, which then under the influence of saliva is formed in the food lump.
Saliva has a fairly important role in the processdigestion of food. It almost entirely consists of water (about 99%). The protein mucin contained in it promotes stickiness, the presence of lysozyme provides food disinfection, and enzymes such as amylase and maltase break down nutrients.
Anatomy of the digestive system shows thatthe next organ behind the oral cavity is the pharynx, which is a muscular organ with certain openings (mouth opening, nasal entrances, entrances to the esophagus and larynx and two tubes from the middle ear). Avoidance of ingestion of food in the path of breathing, the entrance to the larynx is covered by the epiglottis.
The process of swallowing food is due tocuts the muscles of the pharynx, due to which it enters the esophagus and then through the diaphragm - into the stomach. Since the esophagus is a muscle tube, then by cutting these muscles the food is pushed further.
The digestive system includes the stomach, whichis located under the diaphragm in the upper part of the abdominal cavity. Nature has two holes in it - the entrance and the exit. The second is closed by a sufficiently strong blocking muscle (sphincter). Food is delayed in the stomach for a long time (up to 11 hours), where it is exposed to the chemical effects of gastric juice, which is a colorless liquid containing hydrochloric acid. It is with this component that the digestive function is directly performed. Acid also has a harmful effect on the bacteria that enter the human body. Therefore, when there are diseases of the gastrointestinal tract, there is a risk of infection with infectious diseases that are transmitted through the digestive system.
The resulting food gruel from the stomach in portionsGradually enters the intestine through the sphincter. The small intestine begins with the duodenum, which opens the common bile duct and ducts of the pancreas. Here, the digestion of food is completed under the action of pancreatic juice and bile.
From the small intestine processed food graduallymoves into the colon, which has a length of up to 2 meters. Here water is intensively absorbed, and the remains of unwanted food are removed from the body. Due to the large number of different bacteria in the intestine, the absorption of food improves. However, there are negative points. Thus, under the action of these microorganisms, the foodstuffs that are no longer needed are destroyed, and toxic compounds are formed, the elimination of which is responsible for the liver.
The digestive system assigns the liver one of the main roles. After all, it is the largest digestive gland through which all venous blood from the stomach, spleen and intestines passes and is purified.
Thus, the digestive system -a rather complicated system of food processing in the human body, each organ of which has a certain role to play, and if at least one component of this mechanism fails, diseases of the gastrointestinal tract can develop.
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