The heart of man is a kind of motor that drives the blood . But how does the human heart work?
Ensure the constant and unidirectional movement of blood through the vessels is the main purpose of the heart, its most important role in the vital activity of our body.
And the fulfillment of this important work is subordinated to everything: the location of the heart, its structure, the composition of its walls, its innervation and blood supply.
The heart comprises of $ chambers in total. The two right chambers (atrium and ventricle) are intended for pumping venous blood.
The two left chambers of the heart are for pumping arterial blood.
Due to the fact that right and left cameras are reliably separated from each other, venous and arterial blood are never (normally) mixed. And this is despite the fact that one and the same blood pumps one organ!
The atria take blood from the vascular bed and push it into the ventricles. The ventricles, more powerful and strong, give blood to the vessels.
Gradually pumping blood from one chamber to another, separating each chamber from the adjacent valves, a healthy heart never allows a reverse flow of blood.
Therefore, all organs and cells, thanks to a clear work of the heart, receive blood rich in oxygen and nutrients on time, constantly and in sufficient quantity.
The structure of the walls of the heart and the work of the heart
Here too everything is provided!
All cavities of the human heart from the inside are covered with a special connective tissue membrane – endocardium . This membrane provides a “comfortable” stay of blood in the cavities of the heart.
And under it – a powerful muscle layer – the myocardium . This is the layer of muscles that is just needed for this organ! After all, it is he, rhythmically contracting and relaxing, leads to a rhythmic contraction and relaxation of the heart.
All this magnificent muscular power from above is carefully and carefully covered by a layer of connective tissue, which is called the epicardium .
And, finally, the pericardium is a heart bag. It really is some kind of bag, in which the heart is.
But what is important: between the epicardium and this bag is the thinnest layer of liquid. What for? Then, to facilitate the work of the heart. To reduce the frictional force of it against neighboring tissues and organs!
Blood supply to the heart
But that’s not all! The heart is an organ that does not stop working all our life. And this work is not only important, but also difficult.
Imagine: the heart of an adult who is in peace, for one minute, pumps about 5-5.5 liters of blood, and a day – up to 10 000 liters! And this despite the fact that the mass of our hearts is only 250-330 grams! And for one reduction, the heart pushes out only 65-70 ml of blood!
So, caring and wise nature took into account this. I took it into account, and I was worried that such an intensively working body would eat well.
Therefore, our small heart receives 20% of the blood pushed into the aorta! Think about 20% of all the blood that our body receives!
Therefore, the human heart has a well-developed network of its own vessels that carry blood that feeds all the tissues of this important organ.