How does the circulatory system work?

The

circulation system brings the body cells what they need to survive - oxygen and nutrients. Only the most primitive animals lack the circulatory system.

The center of the circulatory or cardiovascular system is the heart, the executive organ of the pump designed to beat many millions of times throughout the life of the body. The heart circulates blood during veins and arteries. Types carrying blood rich in the heart from the heart, provide it in tissues, and then return exhausted red blood back to the heart of the vein for reoxygenation. Red blood cells float in a medium called plasma , which is similar to the interstitial fluid, and forms most of the blood volume, the primary fluid of the circulatory system.

The biggest artery in the human body is aorta, running through the neck and the heart is approaching immediately. The heart oxygenates red blood cells in its chambers or compartments of regulated valves. The lungs get fresh oxygen from the air outside and then pass it to the heart. Complex multicellular organisms such as human beings, needThe air with a large amount of oxygen (15-25%) to survive. Plants and many microbes can survive in an oxygen -free environment - unlike animals, they require carbon dioxide to breathe.

If the heart activity is interrupted, the body is likely to die quickly after the brain damage begins. By using artificial heart stimulation systems, modern medicine is able to maintain the circulatory systems of such victims alive alive in surgery.

Anthropods and molluscs lack typical circulatory systems - in the body, there is no difference between blood and interstitial fluid - a material that simply buys the organs in the necessary oxygen.