What are the two major components of the aerobic energy system?

• A. Transportation of Oxygen and Utilization of Oxygen
• B. Transportation of Oxygen
• C. Utilization of Oxygen
• D. Oxygen Diffusion

Answer: (A)

Two things must happen for aerobic energy production: oxygen has to be delivered to the muscles, and it has to be used by the muscle cells to generate energy. The transportation of oxygen covers the whole pathway from the lungs through the bloodstream to the tissues—the lungs exchange gases, the heart and circulation move the oxygen-loaded blood, and hemoglobin carries oxygen to where it’s needed. The utilization of oxygen occurs inside the cells, mainly in the mitochondria, where oxygen participates in oxidative phosphorylation to produce ATP. Oxygen diffusion is a mechanism that supports moving oxygen in and out, but it isn’t treated as a separate major component of the energy system. So the two major components are transportation of oxygen and utilization of oxygen.