FUNCTIONS OF STRUCTURES OF MAMMALIAN HEART

AORTA: distributes oxygenated blood to all parts of the body
VENA CAVA: it takes deoxygenated blood from all part of the body back to the heart
PULMONARY ARTERY: returns deoxygenated blood from all part of the body back to the heart
PULMONARY VEINS: takes oxygenated blood from from the lungs to the heart
VALVES: (which may be bicusbid, tricuspid or semi lunar) they will avoid back flow of     blood stream i.e blood to flow in one direction.