Final answer:
The number of net ATP produced from one glucose molecule during aerobic respiration is typically around 36, although the theoretical maximum yield is 38 ATP.
Step-by-step explanation:
Approximately how many net ATP are produced via the oxidative energy system from the metabolism of one glucose molecule? The correct answer is 36 to 38 ATP. During cellular respiration, the complete oxidation of glucose includes glycolysis, the Krebs cycle (citric acid cycle), and the electron transport chain (ETC). Glycolysis produces a net of 2 ATP, but these are typically consumed in the process of transporting the NADH produced during glycolysis into the mitochondria, thus not contributing to the net ATP gain. In the Krebs cycle and the ETC, NADH and FADH2 are generated, which then transfer their electrons to the ETC to generate ATP.
The NADH molecules contribute to the production of approximately 30 ATP, while the FADH2 molecules contribute to about 4 ATP. Additionally, a small amount of ATP is generated directly during the Krebs cycle via substrate-level phosphorylation. The theoretical maximum yield of ATP made during aerobic respiration of one glucose molecule is 38, but the actual amount tends to be slightly lower, typically around 36 ATP, when considering the energy costs associated with transport into the mitochondria.