The bloodstream reaches almost every corner of the body to supply the cells with oxygen and nutrients. Learn here why bottlenecks sometimes occur and what helps the blood circulation on the jumps.
For humans, the blood circulation is at the same time a supply and disposal system: it transports oxygen and nutrients to the tissues and organs and removes waste products from the metabolism. At the same time, he is involved in the regulation of the acid-base balance and body temperature and brings immune cells to where they are needed to fight pathogens.
The best way to compare the blood circulation with a complex tube system, which continues to branch and finally reunited to form a closed circuit. This vascular system is more than 100, 000 kilometers long in an adult human and would thus extend more than twice around the equator.
As a driving motor, the heart ensures that the blood stream always remains in motion. With more than 100, 000 strokes a day, the fist-sized muscle pumps the oxygenated and nutrient-rich blood through the arteries from its left ventricle. This is done with high pressure to reach every corner of the body. In the organs, the blood vessels branch into a network of very thin vessels, the capillaries. Mainly in this part of the bloodstream oxygen and nutrients from the blood get into the tissues, at the same time waste substances of the cell metabolism are absorbed.
The blood is not evenly distributed in the body, but in the individual organs always adapted to the current needs. Thus, during sports or heavy physical work, the capillary blood flow of the affected muscles increase by 20- to 50-fold. From the capillaries, the oxygen- and nutrient-poor blood finally flows into the veins and from there back into the right ventricle. Because the flow velocity in the veins has already decreased significantly, small valves ensure that the blood flow always runs in the direction of the heart and the blood does not accumulate.
The blood then enters the lungs from the right ventricle. Here, the red blood cells release the carbon dioxide from the cell metabolism and absorb oxygen. Then it reaches the left ventricle again and is pumped again through the arteries to the organs. During the course of a day, the red life juice will cover some 270, 000 kilometers on this route.