It is the set of organs that allow blood circulation , in order to supply the cells with nutrients and oxygen and thus allow the elimination of carbon dioxide and other waste products.
What is the cardiovascular system?
It is a closed system of vessels (the blood vessels) in which the blood circulates under the pressure of the heart . There are two main components that form it: the systemic circle and the small circle (also called the pulmonary circle). Each of these individual components is made up of arteries, capillaries and veins .
The arteries are tubes with a thick part consisting of elastic tissue and muscle fibers that receive blood from the heart (muscle that works like a real pump). The arteries gradually branch into increasingly thin blood vessels, up to arterioles through which the blood is conveyed into capillaries (small tubes with a thin and permeable wall) by nutrients, gases and waste products. The capillaries then direct the blood towards small vessels, the so-called. venules , which converge to form the veins that bring blood back to the heart.
In the case of systemic circulation , blood from the lungs – rich in oxygen and nutrients – is pumped from the left ventricle (one of the four cavities of the heart in which blood flows) into the aorta , which distributes it to the rest of the body. Once the blood is enriched with carbon dioxide and waste products , it is poured from the vena cava to the right atrium (which is another of the four cavities of the heart).
The pulmonary circulation instead forms a closed circuit between the heart and lungs and begins in the right ventricle, from which the carbon dioxide-rich blood collected from the right atrium – with which it is connected through the tricuspid valve – is pumped inside the ‘ pulmonary artery . This in turn divides into two branches, each directed towards a single lung ; here the branches end, forming the capillaries that collect oxygen at the level of the alveoli . The oxygenated blood is then conveyed into increasingly large vessels, until it flows into the pulmonary veins, which pour it into the right atrium, from which it will pass into the corresponding ventricle via the mitral valve.
What is the cardiovascular system used for?
It allows to distribute oxygen and nutrients to all organs, tissues and cells and to eliminate carbon dioxide and waste substances .
It also serves to convey important components of the immune system (white blood cells) and other molecules that perform numerous functions in the body (such as hormones ) which – precisely through the dense network that makes up the cardiovascular system – can move from one organ to the other. other and from one tissue to another, according to the needs of the organism.