Question

Some students investigated the effect of temperature on the rate of anaerobic respiration in yeast. The apparatus they used is shown in the diagram. The yeast suspension was mixed with glucose solution and the volume of gas collected in five minutes was recorded.If aerobic respiration had been investigated rather than anaerobic respiration, how would you expect the volumes of gas collected at 30°C to differ from these results?

Explain your answer

Answer 1

The volume of gas collected during aerobic respiration at 30°C would be higher than during anaerobic respiration, as aerobic respiration produces more carbon dioxide due to higher ATP yield per glucose molecule.

Step-by-step explanation:

If aerobic respiration had been investigated rather than anaerobic respiration in yeast, the volume of gas collected at 30°C would have been primarily composed of carbon dioxide (CO2). In aerobic conditions, yeast would perform aerobic respiration, which requires oxygen and produces a larger amount of ATP along with CO2 and water as by-products.

During anaerobic respiration or fermentation, yeast convert glucose to ethanol and CO2, but the amount of CO2 produced is less than during aerobic respiration because fermentation is less efficient at ATP production. Because aerobic respiration produces more ATP per glucose molecule, more CO2 is expected to be produced as a by-product. Therefore, if oxygen were present, one would expect to see an increase in the volume of CO2 produced under aerobic conditions compared to anaerobic conditions at the same temperature.