What is the function of the heart and how does it work?

The heart is one of the most important organs in the body, responsible for pumping blood throughout our many tissues. The heart is part of the circulatory or cardiovascular system, along with arteries, veins, capillaries, and the lungs. As blood circulates throughout the body, powered by the heart, it delivers nutrients and oxygen to our tissues and picks up metabolic waste to be excreted.

Below I've shared a simple diagram of the circulatory system. Arteries...

The heart is one of the most important organs in the body, responsible for pumping blood throughout our many tissues. The heart is part of the circulatory or cardiovascular system, along with arteries, veins, capillaries, and the lungs. As blood circulates throughout the body, powered by the heart, it delivers nutrients and oxygen to our tissues and picks up metabolic waste to be excreted.

Below I've shared a simple diagram of the circulatory system. Arteries are depicted in red, and veins in blue. Arteries are responsible for carrying fresh, oxygenated blood away from the heart, and veins are responsible for carrying de-oxygenated blood back towards the heart.

The heartbeat is one of the involuntary or autonomic functions of the body. An electrical impulse from the brain causes the heart to contract (systole) and release (diastole.) The systolic action pushes blood further throughout the circulatory system. The diastolic action fills the heart back up with blood in preparation for the next contraction. 

When deoxygenated blood is returned to the heart, it is pushed on to the lungs, where the cells are supplied with oxygen from the air we breathe. The blood then returns to the heart once more (dropping off a little fresh oxygen on the way) and is pumped throughout the rest of the body. The valves which separate the ventricles and atria of the heart are responsible for regulating the flow of blood throughout the heart and the body.

If you click here, you can see a simple diagram of the directional flow of blood throughout the body.

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