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Picture of Heart Detail

Picture of Heart Detail

The heart is the hardest working muscle in the human body. The heart is a specialized type of muscle consisting of four chambers. The upper chambers of the heart are the atria, and the lower chambers of the heart are the ventricles. Veins of the body return blood to the right atrium., From there, blood flows into the right ventricle, which pumps blood to the lungs. After dumping carbon dioxide and picking up oxygen in the lungs, the blood goes to the left atrium. Oxygenated blood flows into the left ventricle, which pumps blood into the arteries that supply the body.

The heart can be thought of as two hearts. The right side of the heart manages deoxygenated blood, receiving it from the body and delivering it to the lungs. The left side of the heart manages oxygenated blood, receiving it from the lungs and delivering it to the body.

Image Source: MedicineNet, Inc.

Text Reference: National Cancer Institute SEER Training Modules: "Structure of the Heart"