Q116
General ScienceBiology
Muscle fatigue is due to accumulation of
- a.carbon dioxide
- b.creatinine
- c.lactic acid
- d.ethyl alcohol
Answer: (C) lactic acid
During hard exercise the muscles do not get enough oxygen and break down glucose anaerobically into lactic acid; its accumulation causes fatigue and cramps, and the extra oxygen needed afterwards to clear it is called the 'oxygen debt'. Ethyl alcohol and carbon dioxide are the products of anaerobic respiration in yeast (fermentation), and creatinine is a waste product removed by the kidneys.