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Question #16 of 32: In fermentation, ____________ is ___________.

A.NADH....reduced

B. NADH....oxidized

C. ethanol....oxidized

D. NAD+....oxidized

Question #17 of 32: When an organism such as a yeast lives by fermentation, it converts the pyruvate from glycolysis into a different compound, such as alcohol. Why doesn't it secrete the pyruvate directly?

A.The conversion yields one NADH per pyruvate molecule.

B. A buildup of pyruvate in the surrounding environment would be too toxic.

C. The conversion is needed to regenerate the molecules needed from glycolysis.

D. The conversion yields 32 ATP per pyruvate molecule.

Question #18 of 32: A child is born with a rare disease in which mitochondria are missing from skeletal muscle cells. However, the muscles still function. Physicians find that

A.the muscles contain large amounts of carbon dioxide following even mild physical exercise.

B. the muscles require extremely high levels of oxygen to function.

C. the muscles contain large amounts of lactate following even mild physical exercise.

D. the muscle cells cannot split glucose to pyruvate.

Question #19 of 32: Some friends are trying to make wine in their basement. They've added yeast to a sweet grape juice mixture and have allowed the yeast to grow. After several days they find that sugar levels in the grape juice have dropped, but there's no alcohol in the mixture. The most likely explanation is that

A.the mixture needs more sugar, because yeast need a lot of energy before they can begin to produce alcohol.

B. the mixture needs more oxygen, because yeast need oxygen to break down sugar and get enough energy to produce alcohol.

C. the yeast used the alcohol as a carbon source.

D. the mixture needs less oxygen, because yeast only produce alcohol in the absence of oxygen.

Question #20 of 32: In yeast cells,

A.alcohol is produced after glycolysis.

B. alcohol is produced during the citric acid cycle.

C. lactic acid is produced during anaerobic respiration.

D. lactic acid is produced during glycolysis.

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