If glucose is not immediately stored as glycogen, which pathway is most likely used to generate energy?

• A. Glycolysis
• B. Glycogenolysis
• C. Glycogenesis
• D. Gluconeogenesis

Answer: (C)

Energy from glucose is produced most quickly through glycolysis, the pathway that breaks glucose into pyruvate in the cytoplasm and yields ATP and NADH. If glucose isn’t being stored as glycogen, glycolysis directly uses that glucose to make energy. In the presence of oxygen, the pyruvate can then enter the mitochondria for further ATP production via the citric acid cycle and oxidative phosphorylation, boosting overall energy yield. The other processes play different roles: glycogenesis stores glucose as glycogen; glycogenolysis breaks down glycogen to release glucose for energy when stores are needed; gluconeogenesis creates glucose from non-carbohydrate sources, not the immediate energy production from a directly available glucose molecule.