What is the primary metabolic pathway responsible for breaking down glucose into carbon dioxide and water while producing ATP?

The primary metabolic pathway responsible for breaking down glucose into carbon dioxide and water while producing ATP is cellular respiration. This process occurs in multiple stages, starting with glycolysis, followed by the citric acid cycle (Krebs cycle), and then the electron transport chain. During cellular respiration, glucose is oxidized, leading to the release of energy that is captured in the form of ATP, which is the energy currency of cells.

In cellular respiration, glucose (C6H12O6) is completely oxidized to carbon dioxide (CO2) and water (H2O), during which several molecules of ATP are generated. The overall reaction for cellular respiration can be summarized as:

C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP

This pathway is essential for aerobic organisms that rely on oxygen to efficiently extract energy from carbohydrates. In contrast, photosynthesis is a process used by plants to convert light energy into chemical energy, fermentation is an anaerobic process that generates limited ATP and occurs without oxygen, and glycolysis is merely the first stage of cellular respiration that converts glucose into pyruvate, but does not complete the full oxidation process.