Some students investigate the anaerobic respiration of sucrose by yeast (Saccharomyces cerevisiae). The yeast cells produce enzymes that ferment sucrose into ethanol and carbon dioxide gas.
The students carried out this method:
The table shows their results.
$ \begin{array}{|c|c|c|c|c|c|} \hline \text{Temperature } (^\circ\text{C}) & \text{at the start} & \text{after 15 minutes} & \text{after 30 minutes} & \text{after 45 minutes} & \text{after 60 minutes} \\ \hline 15 & 0.0 & 4.0 & 8.5 & 13.0 & 17.5 \\ \hline 25 & 0.0 & 8.5 & 17.5 & 26.0 & 35.0 \\ \hline 35 & 0.0 & 15.0 & 31.0 & 46.5 & 62.0 \\ \hline \end{array} $
Explain why the students measured the cumulative volume of carbon dioxide gas.
Describe how the students should display their results in a graph.
Explain the effect of increasing the temperature on the rate of carbon dioxide production in this experiment.
The students plan a further experiment where they boil the yeast suspension first before adding it to the sucrose solution. Predict what effect this would have on the cumulative volume of carbon dioxide gas produced. Explain your answer.