Final answer:
The two body systems that are most useful when the lungs supply oxygen carried by blood to the cells of the body are the Respiratory and Circulatory systems.
Step-by-step explanation:
The two body systems that are most useful when the lungs supply oxygen carried by blood to the cells of the body are the Respiratory and Circulatory systems.
The respiratory system takes in oxygen and releases waste gases. The main function of the respiratory system is the exchange of gases between the body and the outside air. The circulatory system, on the other hand, delivers oxygen to each of the cells in the body. It moves nutrients, gases, and wastes to and from the cells through the blood vessels.