Final answer:
The fermentation of one glucose molecule under ideal conditions provides a net gain of two ATP molecules for a bacterium. However, in aerobic respiration, up to 38 ATP molecules can be produced from a single glucose molecule.
Step-by-step explanation:
Under ideal conditions, the fermentation of one glucose molecule by a bacterium allows a net gain of two ATP molecules. During glycolysis, a total of four ATP molecules and two NADH molecules are produced from one molecule of glucose. Since two ATP molecules are invested in the early stages of this process, the net gain for the cell is two ATP molecules. In contrast, if the bacteria engage in aerobic respiration, up to 38 ATP molecules can be produced from a single glucose molecule when combining the ATP from glycolysis, the Citric Acid Cycle, and the Electron Transport Chain. However, typically, the number of ATP molecules ranges from 30 to 36 as some energy is used to shuttle intermediates into mitochondria in eukaryotic cells.