The circulatory scheme and the respiratory scheme work nearly simultaneously to double-check that body part tissues obtain sufficient oxygen. Oxygen is needed for cellular functions. The air respired in and held in the lungs is moved to the blood. The body-fluid is distributed by the heart, which pumps the oxygenated body-fluid from the lungs to the body.
Additionally, the two body schemes work simultaneously to eliminate carbon dioxide, which is a metabolic waste product. (Tottora & Derrickson, 2010)
The heart is where circulation and collaboration between the respiratory and the cardiovascular ...