Final answer:
Oxygen is essential for cellular respiration, where it acts as the final electron acceptor, allowing for the complete breakdown of glucose into ATP, carbon dioxide, and water, thus releasing energy that cells need for various functions.
Step-by-step explanation:
The best explanation for how oxygen is involved in the release of energy within an organism is that glucose is broken down in the presence of oxygen to release energy needed by cells (Option C). This process is known as cellular respiration, during which cells convert biochemical energy from glucose into ATP (adenosine triphosphate), and carbon dioxide and water are produced as byproducts. The general equation for cellular respiration is C6H12O6 + 6O2 → 6CO2 + 6H2O + Energy, signifying the oxidative breakdown of glucose when oxygen is present.
Oxygen plays a crucial role as the final electron acceptor in the electron transport chain, allowing glucose to be fully broken down, which in turn maximizes the production of ATP. This ATP then serves as a universal energy currency for cells to perform various functions such as muscle contraction, nerve impulse propagation, and biosynthesis. Without oxygen, organisms would not be able to efficiently extract the full amount of energy stored in glucose.