Page < > of 6 ZOOM + name: 3. In the last reaction of the citric acid cycle, malate is dehydrogenated to regenerate the oxaloacetate necessary for the entry of acetyl-CoA into the cycle: L-Malate + NAD+ → oxaloacetate + NADH + H* AG'° = 30.0 kJ/mol (a) Calculate the equilibrium constant for this reaction at 25 °C. (b) Because AG°' assumes a standard pH of 7, the equilibrium constant calculated in (a) corresponds to [oxaloacetate][NADH] Keq [L-malate][NAD*] The measured concentration of L-malate in rat liver mitochondria is about 0.20 mM when [NAD*]/[NADH] is 10. Calculate the concentration of oxaloacetate at pH 7 in these mitochondria. (c) To appreciate the magnitude of the mitochondrial oxaloacetate concentration, calculate the number of oxaloacetate molecules in a single rat liver mitochondrion. Assume the mitochondrion is a sphere of diameter 2.0 microns.

Page < > of 6 ZOOM + name: 3. In the last reaction of the citric acid cycle, malate is dehydrogenated to regenerate the oxaloacetate necessary for the entry of acetyl-CoA into the cycle: L-Malate + NAD+ → oxaloacetate + NADH + H* AG'° = 30.0 kJ/mol (a) Calculate the equilibrium constant for this reaction at 25 °C. (b) Because AG°' assumes a standard pH of 7, the equilibrium constant calculated in (a) corresponds to [oxaloacetate][NADH] Keq [L-malate][NAD] The measured concentration of L-malate in rat liver mitochondria is about 0.20 mM when [NAD]/[NADH] is 10. Calculate the concentration of oxaloacetate at pH 7 in these mitochondria. (c) To appreciate the magnitude of the mitochondrial oxaloacetate concentration, calculate the number of oxaloacetate molecules in a single rat liver mitochondrion. Assume the mitochondrion is a sphere of diameter 2.0 microns.

Human Anatomy & Physiology (11th Edition)

11th Edition

ISBN:9780134580999

Author:Elaine N. Marieb, Katja N. Hoehn

Publisher:Elaine N. Marieb, Katja N. Hoehn

Chapter1: The Human Body: An Orientation

Section: Chapter Questions

Problem 1RQ: The correct sequence of levels forming the structural hierarchy is A. (a) organ, organ system,...

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2.3
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