Assume you have a solution containing the pyruvate dehydrogenase complex and all the enzymes of the citric acid cycle, but none of the metabolic intermediates. When you supplement this solution with 5 μmoles each of pyruvate, oxaloacetate, coenzyme A, NAD+, FAD, GDP, and Pi , you find that 5 μmoles of CO2 are evolved and then the reaction stops. When you add alcohol dehydrogenase and its substrate acetaldehyde, additional CO2 is produced. (a) How do you explain this result? (b) How many μmoles of acetaldehyde are required to allow complete oxidation of the pyruvate to 15 μmoles of CO2?

Assume you have a solution containing the pyruvate dehydrogenase complex and all the enzymes of the citric acid cycle, but none of the metabolic intermediates. When you supplement this solution with 5 μmoles each of pyruvate, oxaloacetate, coenzyme A, NAD+, FAD, GDP, and Pi , you find that 5 μmoles of CO2 are evolved and then the reaction stops. When you add alcohol dehydrogenase and its substrate acetaldehyde, additional CO2 is produced. (a) How do you explain this result? (b) How many μmoles of acetaldehyde are required to allow complete oxidation of the pyruvate to 15 μmoles of CO2?

Concepts of Biology

1st Edition

ISBN:9781938168116

Author:Samantha Fowler, Rebecca Roush, James Wise

Publisher:Samantha Fowler, Rebecca Roush, James Wise

Chapter4: How Cells Obtain Energy

Section: Chapter Questions

Problem 17CTQ: Both prokaryotic and eukaryotic organisms carry out some form of glycolysis. How does ha fact...

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