Power Up for 2026: Conquer the AQA A-Level PE Energy Systems Challenge!

Glycolysis produces a net gain of ATP per glucose molecule. At the start, 2 ATP are invested to phosphorylate glucose and keep it trapped inside the cell, forming high-energy intermediates. Later, the pathway generates 4 ATP through substrate-level phosphorylation as the intermediates are converted to pyruvate. Because two ATP were spent initially, the overall net production is 2 ATP per glucose. Additionally, glycolysis yields 2 NADH, which can contribute to ATP production further if the NADH is shuttled into the mitochondria under aerobic conditions. The question is asking for net ATP produced in glycolysis, so the correct value is 2.