Final answer:
Anaerobic glycolysis is the process of breaking down glucose into lactate to produce ATP when oxygen is scarce. Only 2 ATP molecules are produced per glucose molecule, and this process is critical during intense exercise or in cells lacking mitochondria. It also has applications in food production.
Step-by-step explanation:
Glycolysis is a biochemical pathway that breaks down glucose to form pyruvate, ultimately yielding a small amount of ATP without the need for oxygen. Under anaerobic conditions, such as during intense exercise or in cells lacking mitochondria, glycolysis is followed by fermentation processes to regenerate essential coenzymes needed for glycolysis to continue. The most common form of fermentation in human cells is lactic acid fermentation, where pyruvate accepts electrons from NADH, forming lactate and regenerating NAD+, which is essential for glycolysis to proceed and maintain ATP production in the absence of oxygen.
In the process of converting one molecule of glucose to two molecules of lactate, only 2 ATP are produced, which is relatively inefficient compared to aerobic respiration. Moreover, 93% of the energy from glucose remains stored in the lactate, signifying the incomplete oxidation of glucose under anaerobic conditions. This pathway is crucial in circumstances where oxygen supply is limited, such as during vigorous exercise leading to muscle fatigue, or in cells like erythrocytes that lack mitochondria. The lactate produced can be transported to the liver, where it is converted back into glucose or pyruvate via the Cori cycle.
Overall, anaerobic glycolysis is an important biological mechanism that ensures the continuous production of energy, albeit limited, allowing organisms to survive short periods of oxygen scarcity. It also has practical applications, like in the production of yogurt and soy sauce without oxygen.