Divisions of the Heart

The human heart is divided into four main chambers. The right and left atrium and the right and left ventricle work together to pump blood throughout the body and supply nutrients and oxygen to all organs. Blood flows into the heart through the superior vena cava into the right atrium. The right atrium is larger then the left atrium and has much thinner muscle walls due to its stronger need to pump the blood further in the body then any other compartment of the heart. The blood that flows into the heart from the vena cava is blood that has already traveled through the body and dispersed nutrients and oxygen to the organs. The blood then travels through the coronary sinus and tricuspid valve into the right ventricle. The right ventricle pumps the blood out of the heart and into the lungs in order to be re oxygenated. Once the blood has traveled through the lungs and has been resupplied of oxygen it then travels through the pulmonary veins back to the heart into the left atrium. The left atrium is much smaller then the right atrium because it does not need as much strength to pump the blood through the body. Once the left atrium fills with blood, the bicuspid valve opens in a one way direction and allows the blood to flow into the left ventricle. The left ventricle then contracts and sends the blood out of the heart and into the rest of the body. The blood travels the full extent of the body through the arteries and capillaries and passes into the veins which return the blood back into the heart to start the cycle over again. The heart pumps the blood in this continuous cycle to keep the body alive.