3. POSTERIOR VIEW left pulmonary arteries left atrium right pulmonary arteries right pulmonary veins inferior vena cava
4. body cell O 2 CO 2 O 2 glucose CO 2 H 2 o pulmonary vein superior vena cava aorta pulmonary trunk (to arteries) tricuspid valve bicuspid valve pulmonary semilunar valve aortic semilunar valve left ventricle right ventricle right atrium left atrium lungs inferior vena cava