Fermentation is the process of yeast respiring anaerobically. This produces ethanol, carbon dioxide and energy.
Glucose --> Ethanol + Carbon Dioxide (+ Energy)
C6H12O6 --> 2C2H5OH + 2CO2 (+ Energy)
This process can be used to make beer and wine.
Yeast can also respire aerobically, releasing more energy. It is the same for yeast as for plants and animals.
Glucose + Oxygen --> Carbon Dioxide + Water (+ Energy)
Aerobic or anaerobic depends on the presence of oxygen. Yeast prefers aerobic because more energy, so for fermentation to take place, there must be no oxygen.
The faster yeast respires, the faster it reproduces. The growth…