Circulation of Blood Through the Heart

Blood Circulation Through the Body

Below are flow diagrams that show blood circulation through the heart and body.


Blood circulates through the heart continuously. Both sides, the left and the right, work together to pump blood all over the body. Blood enters the heart through the right side through two large veins. These veins are called the inferior and super vena cava. These empty oxygen-poor blood from the body into the right atrium of the heart. Once the atrium contracts, the blood flows into the right ventricle through the tricuspid valve. Once the ventricle is full the valve shuts. This prevents blood from flowing backward into the atria, during contraction. Blood leaves through the heart from the pulmonic valve into the pulmonary artery and to the lungs, where it receives oxygen.

While the right side is working, the left side is as well. The left side of the heart has a pulmonary vein that empties oxygen rich blood from the lung into the left atrium. The atrium contracts, as blood flows into the left ventricle through the open mitral valve. When the ventricle is full, the mitral valve shuts. As seen in the right side, the mitral valve prevents blood from flowing backward. Once the ventricle contracts, the blood leaves the aortic valve in the aorta and all over the body.


The lungs receive and give blood for pulmonary circulation of the body. After the blood has traveled through the pulmonic valve, it enters a person’s lungs. From the pulmonic valve, blood travels from the pulmonary artery to tiny capillary vessels in the lungs. Oxygen from tiny air sacs, through the walls of the capillaries is switched with carbon dioxide. This exchange is a bi product of metabolism. The carbon dioxide then leaves when a person exhales. The blood is the purified and oxygenated and travels to the left side of the hear through the pulmonary veins.