Final answer:
Most organisms perform lactic acid fermentation, converting pyruvic acid to lactic acid. This process does not produce carbon dioxide and provides additional ATP molecules for energy.
Step-by-step explanation:
Most organisms perform lactic acid fermentation, which is a type of fermentation that converts pyruvic acid to lactic acid. This process is carried out by certain bacteria, such as the bacteria in yogurt, as well as by muscle cells during intense activity. Lactic acid fermentation does not produce carbon dioxide. Instead, it produces additional molecules of ATP, allowing glycolysis to continue and providing energy to the cells.