How many ATP molecules are produced during lactic acid fermentation?

Lactic acid fermentation is an anaerobic process that occurs in some bacteria and animal cells, such as in muscles during strenuous exercise when oxygen levels are low. During this process, glucose is partially broken down without the use of oxygen, resulting in the production of lactic acid and a net gain of 2 ATP molecules.

This particular fermentation pathway follows glycolysis, where glucose is converted into pyruvate, generating 2 ATP in the process. In the absence of oxygen, pyruvate is then transformed into lactic acid through the action of lactate dehydrogenase. Importantly, even though the yield of ATP from lactic acid fermentation is limited compared to aerobic respiration, it is still significant for cells relying on quick bursts of energy or in low-oxygen environments. Therefore, the correct answer reflects the total ATP produced during this fermentation process, which is 2.