Yeast is a fungus that is used in making bread. As the yeast cells reproduce and feed, they ferment sugars to produce ethyl alcohol and carbon dioxide gas. The carbon dioxide forms bubbles in the dough, causing the dough to rise.
How fast the dough rises depends on temperature.
Three portions of dough weighing exactly the same are allowed to rise for 45 minutes at three different temperatures. At the end of forty-five minutes, the volume of each portion is measured. The results of the experiment are listed in the table at the left.
Based on the chart, which statement is an accurate conclusion?
A . Yeast cells at 20° C metabolize the fastest.
B . Yeast cells at 25° C metabolize the fastest.
C . Yeast cells at 37° C metabolize the fastest.
D . Carbon dioxide slows yeast cell metabolism.
E . Carbon dioxide speeds up yeast cell metabolism.
Answer: C