How does the respiratory system work together with the cardiovascular system?

O2 Delivery: The lungs exchange co2 from metabolism for o2. The heart delivers a carefully calibrated amount of blood to the body to match o2 delivered to o2 needed. That's why heart rate goes up w/ exercise. The lungs gets their blood from the right ventricle, and this blood comes back to the left atrium where it is then ejected to the body by the left ventricle.