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The heart and blood vessels, which are divided into arteries, veins and capillaries. The heart is responsible for pumping the blood throughout the blood vessels and is divided into four chambers, two of which are responsible for moving poorly oxygenated blood and two of which move highly oxygenated blood. Oxygenated blood, which is pumped through the body via the arteries, supplies the body's tissues with oxygen that they need to live. Blood in the arteries is under high pressure; however, which could damage the tissue, so this oxygenated blood first needs to go to the capillaries, which are very small and low-pressure blood vessels that are responsible for supplying the oxygenated blood to the tissues. Once the capillaries have delivered their oxygen, they also absorb excess carbon dioxide into the blood and then deliver it to the veins, which then supply the blood back to the heart. This system is called...
What is the cardiovascular system