Final answer:
Without KOH in the aerobic respiration experiment, the results would likely show decreased oxygen consumption because the produced CO2 is not absorbed, which interferes with accurately measuring the rate of oxygen uptake.
Step-by-step explanation:
If you performed the aerobic respiration experiment without adding KOH (potassium hydroxide) to the microrespirometers, you would predict a decreased oxygen consumption as one of the potential outcomes. KOH is added in such experiments to absorb CO2, which is produced during aerobic respiration. By removing CO2, the only gas phase change in the system is due to the consumption of oxygen for respiration, allowing for more accurate measurement of oxygen consumption.
Without KOH to absorb the CO2, the pressure in the microrespirometer would not decrease as much as it should due to the presence of the produced CO2. This would give the appearance of decreased oxygen consumption because the CO2 produced would take up space, masking the full extent of oxygen uptake. This is important because oxygen is a critical final electron acceptor in the electron transport chain during aerobic respiration, allowing for the production of a large amount of ATP – typically 36-38 ATP molecules per molecule of glucose. Without reliable oxygen consumption data, it would be difficult to measure the rate of respiration accurately.