Final answer:
In the absence of oxygen, a cell's ability to convert glucose into ATP is greatly decreased, allowing for only 2 ATP molecules to be produced per glucose molecule due to anaerobic glycolysis.
Step-by-step explanation:
The cell's ability to convert the stored energy of glucose to usable ATP in the absence of oxygen is greatly decreased. Under anaerobic conditions, cells undergo glycolysis, which yields a net of only two ATP molecules per glucose molecule, rather than the 36-38 ATP molecules that are produced during aerobic respiration.
This limited ATP production constrains the energy available to the cell for metabolic activities.