Final answer:
The term 'oxygen debt' refers to the amount of oxygen required by liver cells to convert lactic acid into glucose or glycogen, typically after anaerobic exercise.
Step-by-step explanation:
The amount of oxygen liver cells require to support the conversion of lactic acid to produce glucose or glycogen is known as the oxygen debt. During strenuous exercise, muscles may use anaerobic respiration to rapidly produce ATP when oxygen delivery is insufficient.
This process generates lactic acid as a byproduct, which is transported to the liver. In the liver, lactic acid can be converted back to pyruvate or glucose through the Cori cycle, a process that requires oxygen. Thus, the term oxygen debt refers to the extra oxygen needed to metabolize lactic acid and restore the body to its pre-exercise state.