The capillaries of the lung receive an immense blood supply, equal to that distributed to all other parts of the entire body. The alveoli expand and contract 15,000 times a day. During activity ...

What Is the Respiratory System? The respiratory system is the organs and other parts of your body involved in breathing, when you exchange oxygen and carbon dioxide. All the cells in your body ...

From there, the heart pumps the blood through an artery that branches to distribute blood to itself and other body parts (except the lungs). The lungs work with the heart to oxygenate blood.