Consider a cell that requires much more ribose5-phosphate than NADPH. The cell needs ribose 5-phosphate but has a relatively high concentration of NADPH and a low concentration of NADP+. These conditions may occur in rapidly dividing cells. What is the fate of glucose 6-phosphate, glycolytic intermediates, and pentose phosphate pathway intermediates in this cell? Most of the glucose 6-phosphate enters the pentose phosphate pathway. One molecule of glyceraldehyde 3-phosphate and two molecules of fructose 6-phosphate are used to generate three molecules of ribose 5-phosphate. Most of the glucose 6-phosphate enters the glycolytic pathway and is converted to fructose 6-phosphate and glyceraldehyde 3-phosphate. Glycolytic intermediates can only enter the pentose phosphate pathway through conversion to pyruvate and subsequent gluconeogenesis. Under the given conditions, all triose phosphates are converted to pyruvate by the glycolytic pathway. The oxidative pentose phosphate pathway reaction catalyzed by glucose 6-phosphate dehydrogenase is slowed down.

Consider a cell that requires much more ribose5-phosphate than NADPH. The cell needs ribose 5-phosphate but has a relatively high concentration of NADPH and a low concentration of NADP+. These conditions may occur in rapidly dividing cells. What is the fate of glucose 6-phosphate, glycolytic intermediates, and pentose phosphate pathway intermediates in this cell? Most of the glucose 6-phosphate enters the pentose phosphate pathway. One molecule of glyceraldehyde 3-phosphate and two molecules of fructose 6-phosphate are used to generate three molecules of ribose 5-phosphate. Most of the glucose 6-phosphate enters the glycolytic pathway and is converted to fructose 6-phosphate and glyceraldehyde 3-phosphate. Glycolytic intermediates can only enter the pentose phosphate pathway through conversion to pyruvate and subsequent gluconeogenesis. Under the given conditions, all triose phosphates are converted to pyruvate by the glycolytic pathway. The oxidative pentose phosphate pathway reaction catalyzed by glucose 6-phosphate dehydrogenase is slowed down.

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter2: Cell Physiology

Section: Chapter Questions

Problem 10RE: Using the answer code on the right, indicate which form of energy production is being described: 1....

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