Internal environment of the body and its meaning
The phrase "the internal environment of the body"appeared due to the French physiologist Claude Bernard, who lived in the XIX century. In his works he emphasized that the necessary condition for the life of the organism is the maintenance of constancy in the internal environment. This provision was the basis for the theory of homeostasis, which was formulated later (in 1929) by scientist Walter Cannon.
Homeostasis is the relative dynamic constancy of the internal environment,
The internal environment of the body, consisting of extracellular fluid, contains:
- lymph (a component of the tissue fluid) - 2 liters;
- blood - 3 liters;
- interstitial fluid - 10 liters;
- transcellular fluid - about 1 liter (it includes spinal, pleural, synovial, intraocular fluid).
All of them have different composition and differ in their functional
As already noted, the internal environment of the body inas one of the components contains blood. It consists of plasma, water, proteins, fats, glucose, urea and mineral salts. Its main location is the blood vessels (capillaries, veins, arteries). Blood is formed due to absorption of proteins, carbohydrates, fats, water. Its main function is the interrelation of organs with the external environment, the delivery to the organs of the necessary substances, the removal of the decay products from the body. It also performs protective and humoral functions.
The lymph consists of water and dissolved in itorganic substances. It is in the lymphatic system, which consists of lymphatic capillaries, vessels drained into two ducts and flowing into the hollow veins. Formed by tissue fluid, in pouches, which are located at the ends of lymphatic capillaries. The main function of lymph is the return of tissue fluid to the bloodstream. In addition, it filters and disinfects the tissue fluid.
As we see, the internal environment of the body is a combination of physiological, physico-chemical, respectively, and genetic conditions that affect the viability of a living being.