Becker's World of the Cell (9th Edition)
9th Edition
ISBN: 9780321934925
Author: Jeff Hardin, Gregory Paul Bertoni
Publisher: PEARSON
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Chapter 9, Problem 9.6PS
Ethanol Intoxication and Methanol Toxicity. The enzyme alcohol dehydrogenase was mentioned in this chapter because of its role in the final step of alcoholic fermentation. However, the enzyme also occurs commonly in aerobic organisms, including humans. The ability of the human body to catabolize the ethanol in alcoholic beverages depends on the presence of alcohol dehydrogenase in the liver. One effect of ethanol intoxication is a dramatic decrease in the NAD+ concentration in liver cells, which decreases the aerobic utilization of glucose. Methanol, on the other hand, is not just an intoxicant; it is a deadly poison due to the toxic effect of the formaldehyde to which it is converted in the liver.
- (a) Why does ethanol consumption lead to a reduction in NAD+ concentration and to a decrease in aerobic respiration?
- (b) Most of the unpleasant effects of hangovers result from an accumulation of acetaldehyde and its metabolites. Where does the acetaldehyde come from?
- (c) The medical treatment for methanol poisoning usually involves administration of large doses of ethanol. Why is this treatment effective?
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Chapter 9 Solutions
Becker's World of the Cell (9th Edition)
Ch. 9 - How are catabolic and anabolic pathways similar?...Ch. 9 - Prob. 9.2CCCh. 9 - Why do oxidation and reduction reactions always...Ch. 9 - How can glucose be oxidized in the absence of...Ch. 9 - In the absence of oxygen, why is it necessary to...Ch. 9 - Prob. 9.6CCCh. 9 - Prob. 1QCh. 9 - Why dont glycolysis (glucose to pyruvate) and...Ch. 9 - Why are the key regulatory enzymes in glycolysis...Ch. 9 - Why do cancer cells carry out high rates of...
Ch. 9 - High-Energy Bonds. When first introduced by Fritz...Ch. 9 - The History of Glycolysis. Following are several...Ch. 9 - Glycolysis in 25 Words or Fewer. Complete each of...Ch. 9 - Energetics of Carbohydrate Utilization. The...Ch. 9 - QUANTITATIVE Glucose Phosphorylation. The direct...Ch. 9 - Ethanol Intoxication and Methanol Toxicity. The...Ch. 9 - Propionate Fermentation. Although lactate and...Ch. 9 - QUANTITATIVE Glycolysis and Gluconeogenesis. As...Ch. 9 - Prob. 9.9PSCh. 9 - Youve Got Some Explaining to Do. Explain each of...Ch. 9 - Arsenate Poisoning. Arsenate (HAsO42) is a potent...Ch. 9 - Life Without Phosphofructokinase. Many bacteria do...Ch. 9 - Prob. 9.13PS
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