What is a consequence of prolonged reliance on anaerobic metabolism?

What is a consequence of prolonged reliance on anaerobic metabolism?

• A. It can lead to tissue damage and death due to insufficient ATP and acidosis.
• B. It increases mitochondrial ATP production efficiency.
• C. It improves oxygen utilization efficiency in tissues.
• D. It reduces lactic acid accumulation.

Answer: (A)

When tissues rely on anaerobic metabolism for an extended period, energy production plummets. Glycolysis without mitochondria yields only about 2 ATP per glucose, far less than the 30–32 ATP produced by aerobic respiration. That limited ATP means critical processes like the Na+/K+ pump fail, leading to ion imbalance, cell swelling, and ultimately cell injury or death. At the same time, pyruvate is converted to lactate to regenerate NAD+, causing lactic acid buildup and acidosis. This acidosis further impairs enzyme function and cellular processes, compounding damage. Because of the severe energy shortfall and acidosis, tissue damage and cell death can occur with prolonged anaerobic metabolism. In contrast, increasing mitochondrial ATP production efficiency or improving oxygen utilization does not happen under anaerobic conditions. Lactic acid accumulation would not be reduced by prolonged reliance on anaerobic metabolism; it typically increases as lactate is produced to sustain glycolysis without oxygen.

When tissues rely on anaerobic metabolism for an extended period, energy production plummets. Glycolysis without mitochondria yields only about 2 ATP per glucose, far less than the 30–32 ATP produced by aerobic respiration. That limited ATP means critical processes like the Na+/K+ pump fail, leading to ion imbalance, cell swelling, and ultimately cell injury or death. At the same time, pyruvate is converted to lactate to regenerate NAD+, causing lactic acid buildup and acidosis. This acidosis further impairs enzyme function and cellular processes, compounding damage. Because of the severe energy shortfall and acidosis, tissue damage and cell death can occur with prolonged anaerobic metabolism.

In contrast, increasing mitochondrial ATP production efficiency or improving oxygen utilization does not happen under anaerobic conditions. Lactic acid accumulation would not be reduced by prolonged reliance on anaerobic metabolism; it typically increases as lactate is produced to sustain glycolysis without oxygen.