The major purpose of the cardiovascular system is to provide oxygenated blood to our cells and return deoxygenated blood to the heart, where it travels to the lungs to be reoxygenated. First of all, deoxygenated blood comes from the body, from the venous system, and travels via the inferior (from lower body) and superior (from upper body) vena cava to the right atrium. Blood flows from the right atrium to the right ventricle and out to the lungs through the pulmonary artery. The blood then picks up oxygen in the lungs and travels via the pulmonary vein to the left atrium and down to the left ventricle. From the left ventricle, oxygenated blood is pumped out through the aorta to the body.


