When there isn’t enough oxygen for aerobic respiration, fermentation might occur. There are different types of fermentation. In humans, fermentation occurs when a person is using ATP quickly, and oxygen cannot get to the muscles fast enough. In human muscle cells, fermentation leads to the production of lactic acid. When lactic acid builds up in muscles, it can cause soreness. Other organisms also use fermentation, and sometimes the reactions are very useful to us. When yeast ferments in dough, the carbon dioxide that is released makes the dough rise.

Based on the passage, when might fermentation occur?

A
after a person eats bread

B
when carbon dioxide is absent

C
when bread does not rise correctly and comes out flat

D
when a person is running as fast as she can to catch a bus

1 answer

Based on the passage, fermentation might occur D when a person is running as fast as she can to catch a bus. This is because the passage explains that fermentation occurs in human muscle cells when there isn't enough oxygen for aerobic respiration, such as during intense physical activity.