The circulatory system consists of three independent systems that work together: the heart (cardiovascular), lungs (pulmonary), and arteries, veins, coronary and portal vessels (systemic).

Your circulatory or cardiovascular system serves a vital function by delivering oxygen and nutrients to all the organs and tissues of your body. Learn more about how the circulatory system works ...

Your circulatory system is how your oxygen-rich blood flows from your heart through your body, washing over all your vital organs, then returning oxygen-poor blood to your heart.

What are the main arteries of the body? Illustrations and lists breakdown this major part of your circulatory system.