Final answer:
Glucose is transformed into lactic acid and ethanol through the process of fermentation, which includes glycolysis and the reduction of pyruvic acid to ethanol with the simultaneous oxidation of NADH to NAD+.
Step-by-step explanation:
The chemical transformation process in which glucose (C6H12O6) is converted to lactic acid (C3H6O3) and ethanol (C2H5OH) involves a series of reactions commonly known as fermentation. In the absence of oxygen, glucose is first split into two molecules of pyruvic acid through a process called glycolysis. Then, under low oxygen conditions or in the presence of specific organisms like yeast, pyruvic acid can be reduced to either lactic acid or converted into acetaldehyde and carbon dioxide, which is further reduced to ethanol. The reduction of acetaldehyde to ethanol also results in the oxidation of NADH back to NAD+, allowing the fermentation process to continue. This pathway is critical for organisms like yeast to produce energy in the absence of oxygen and is exploited by humans to produce alcoholic beverages and raise bread.