Blood vessels run through the entire human body, providing continuous nutrition to the organs and tissues. The heart is the central organ of the circulatory system that acts like a huge pump, pumping blood through the body.

Oxygenated blood is carried from the heart through the large vessels, called arteries, which, in turn, redirect it to smaller vessels — called capillaries. Capillaries deliver oxygenated blood to the most distant parts of the body, feeding the cells, and then they carry the “waste” blood that is saturated with carbon dioxide into the veins. Through the veins, the blood returns back to the heart, in order to then pass through the lungs again, get oxygenated, and begin the next cycle.

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