the Small intestine consists of three departments - duodenal, lean and podvzdoshnoj guts. Here the food arriving from a stomach is split and soaked up in blood.
The Thin gut-it a component of a digestive path connecting a stomach with thick intestines. It represents a soft twisting tube from muscular and mucous covers, dense rings laid in a belly cavity. The small intestine total length makes about 6 metres.
Allocate three departments of a small intestine: duodenal, lean and podvzdoshnuju guts. The duodenal gut is bent in the form of the letter "Р" also it is attached to a back wall of a belly cavity brjushinoj (a cover covering a belly cavity from within). Lean and podvzdoshnaja guts free crinkles lie in a fold brjushiny approximately in the center of a belly cavity.
Humidifying and crushing
About 90% of food consumed by us it is soaked up in blood from small intestines. By this moment the eaten breakfast or a dinner is transformed beyond recognition. Humidified with a saliva and the food chewed in a mouth arrives on a gullet in a stomach where under the influence of digestive juice it turns to a solution named a chemical moustache. At a following stage this solution some hours definitively are digested in a small intestine.
Chemical moustache carefully mixed and split in a stomach is pushed out through a narrow aperture - the gatekeeper - in a duodenal gut where again mixes up as a result of reductions of its muscular walls. With receipt of a portion of food in a small intestine circular muscles at first are reduced, dividing it into separate parts. Then other group of the muscles located between them, forming even smaller segments is reduced; circular in the meantime relax. These measured repeating movements - rhythmic segmentation - occur to frequency of 12-16 times in a minute.
Longitudinal muscles Simultaneously get down to business, being alternately reduced and relaxing pendular movements. Here in such mixer the chemical moustache carefully mixes up with digestive juice of intestines. Then waves peristaltiki, running from duodenal to podvzdoshnoj guts, push all this mix further, to thick intestines. In usual conditions we do not feel intestines work, but after a dense meal we can feel weight, and in case of food poisoning it will have an effect sharp and rather painful spasms.
The Chemical moustache arriving from a stomach in a duodenal gut, already contains hydrochloric acid and enzimy, necessary for splitting of large molecules of food, therefore its acidity is very high. It will be neutralised by the enzymes of a small intestine containing bicarbonate (an alkaline substance). Some of these enzymes are developed by special cages in intestines walls, others - a pancreas and a bilious bubble.
The structure of a small intestine helps an organism to soak up nutrients effectively. Its walls are thin enough, but are collected in folds, as if the goffered hose of a vacuum cleaner thanks to what the area of an internal surface essentially extends. All it is covered similar to microscopic fingers vyrostami, or fibers, and by the form reminds a velvet. Each fiber, in turn, is covered by smaller microfibers that increases soaking up surface even more. Its total area at the average adult person makes over 16,5 sq. m.
The Smallest molecules formed as a result of splitting of food carbohydrates and fibers, get into a cellular cover of fibers, and therefrom arrive in capillaries of blood system. Capillaries run into small blood vessels, and those, in turn - in larger and, at last, in hepatic vorotnuju a vein. In a liver in which the given vein conducts, there are next stages of splitting, and only after that nutrients are delivered to all cages of an organism.
Processing of fats
Fats Containing in food do not arrive directly in blood, and at first are soaked up by special lacteal vessels of fibers. They are a part of lymphatic system, and nutrients passing on them get to blood from lymphatic system, passing a liver.
The nutrients which have Arrived in a blood-groove find, at last, the form, suitable for synthesis of more difficult molecules necessary for maintenance of a life and health of an organism. So, entering reaction with oxygen and forming water, carbonic gas and azotosoderzhashchie substances, these molecules liberate energy to a body for maintenance of processes of ability to live. The fulfilled materials arrive in thick intestines and leave in the form of excrement.