Question

if a runner is doing vigorous exercise, which results from the anaerobic cellular process?
accumulation of lactic acid
accumulation of oxygen
depletion of ethanol
depletion of carbon dioxide

Explanation:

During vigorous exercise, when oxygen supply is limited, human cells undergo anaerobic respiration. In anaerobic respiration (lactic acid fermentation in humans), glucose is partially broken down. The end - product of lactic acid fermentation is lactic acid. Oxygen is used up in cellular respiration (both aerobic and anaerobic, but in anaerobic, it is not the final electron acceptor in the same way as in aerobic). Ethanol is a product of alcoholic fermentation (which occurs in yeast, not in human muscle cells during exercise). Carbon dioxide is a product of aerobic respiration (in humans) and also in alcoholic fermentation (in yeast), but not depleted during anaerobic respiration in human muscle cells.

Answer:

accumulation of lactic acid