The lungs are the organs that are most crucial in
expelling cellular carbon dioxide waste. Lungs are the most important organ of
the respiratory system. They excrete these wastes through the process of
diffusion and exhalation. Without the proper excretion of carbon dioxide by the
lungs, the blood will be left without oxygen and might be toxic to course
through the bloodstream. The lungs are responsible for converting unoxygenated
blood into oxygenated blood. Through this process carbon dioxide is expelled as
the by-product.