Final answer:
Yeasts produce ethyl alcohol and carbon dioxide gas through alcoholic fermentation in the absence of oxygen. Ethyl alcohol is used in alcoholic beverages, and carbon dioxide is used in bread making and in carbonating beverages.
Step-by-step explanation:
Without the presence of oxygen, yeasts are used to produce ethyl alcohol (ethanol) and carbon dioxide (CO2) through a biochemical process known as fermentation. Yeasts, which are single-celled eukaryotic organisms, perform this process known as alcoholic fermentation.
The ethyl alcohol produced is commonly used in the production of alcoholic beverages such as wine and beer, and the carbon dioxide is instrumental in making bread rise and providing carbonation in sparkling wines.
Yeast cells are capable of switching between aerobic respiration and fermentation depending on the availability of oxygen, making them facultative anaerobes. During the fermentation of glucose (C6H12O6), the balanced chemical reaction is:
C6H12O6 --> 2C2H5OH + 2CO2
This reaction depicts the transformation of glucose to ethanol and carbon dioxide under anaerobic conditions.