The two half reactions for beginning and end of the electron transport chain are given below in standard form. Calculate & for the overall process. Using the Nernst equation (AG° = -n Fo, F= 96.485 kJ/volt mol), calculate AG°. Explain the need for a stepwise process in the electron transport chain. NAD* + H+ + 2 e- = NADH ½ 0г + 2H+ + 2е- = H20 = -0.32v E = +0.82V

The two half reactions for beginning and end of the electron transport chain are given below in standard form. Calculate & for the overall process. Using the Nernst equation (AG° = -n Fo, F= 96.485 kJ/volt mol), calculate AG°. Explain the need for a stepwise process in the electron transport chain. NAD* + H+ + 2 e- = NADH ½ 0г + 2H+ + 2е- = H20 = -0.32v E = +0.82V

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter27: Metabolic Integration And Organ Specialization

Section: Chapter Questions

Problem 4P

See similar textbooks

Similar questions

Energetics of the Hexokinase Reaction The standard-state free energy change. Gfor the hexokinase reaction, is â€” 1 6.7 kJ/mol. Use the values in Table I to calculate the value of Gfor this reaction in the erythrocyte at 37Â°C.
Characterizing Glycolysis List the reactions of glycolysis that a. are energy consuming (under standard-stale conditions), b. are energy yielding (under standard-state conditions), c. consume ATP. d. yield ATP e. are strongly influenced by changes in concentration of substrate and product because of their molecularity. f. are at or near equilibrium in the erythrocyte (see Table 18.2).
Using the ActiveModel for enoyl-CoA dehydratase, give an example of a case in which conserved residues in slightly different positions can change the catalytic rate of reaction.
Distinguishing the Mechanisms of Class I and Class I Aldolases Fructose bisphosphate aldolase in animal muscle is a class 1 aldolase, which forms a Schiff base intermediate between substrate (for example. fructose-1, 6-bisphosphate or dihydroxyacetone phosphate) and a lysine at the active site (see Figure I8.12). The chemical evidence for this intermediate conies from studies with aldolase and the reducing agent sodium borohydride, NaBH4. Incubation of the enzyme with dihydroxyacetone phosphate and NaBH4 inactivates the enzyme. Interestingly, no inactivation is observed if NabH4 is added to the enzyme in the absence of substrate. Write a mechanism that explains these observations and provides evidence for the formation of a Schiff base intermediate in the aldolase reaction.
The Relative Efficiency of ATP Synthesis in Noncyclic versus Cyclic Photophosphorylation If noncyclic photosynthetic electron transport leads to the translocation of 7 H+/2e- and cyclic photosynthetic electron transport leads to the translocation of 2 H+/e-, what is the relative photosynthetic efficiency of ATP synthesis (expressed as the number of photons absorbed per ATP synthesized) for noncyclic versus cyclic photophosphorylation? (Assume that the CF1CF0-ATP synthase yields 3 ATP/14 H+.)
Based on your knowledge of the structure of NAD+ and an assumption that coenzyme dissociation is the rate limiting step of the alcohol dehydrogenase mechanism, hypothesize why a N249W mutation at the coenzyme binding site would increase the rate of catalysis.
Examine the ActiveModel for alcohol dehydrogenase and describe the structure and function of the catalytic zinc center.
Using the Nernst equation, calculate the equilibrium potential for Ca2 and for C1 from the following sets of data: a. Given [ Ca2+ ]0=1mM,[ Ca2+ ]i=100nM, find Eca2+ b. Given [ Cl- ]0=110mM,[ Cl- ]i=100mM, find Ecl
Using the answer code on the right, indicate which form of energy production is being described: 1. takes place in the mitochondrial matrix 2. produces H2O as a by-product 3. results in a rich yield of ATP 4. takes place in the cytosol 5. processes acetyl-CoA 6. takes place in the mitochondrial innermembrane cristae 7. converts glucose into two pyruvate molecules 8. uses molecular oxygen 9. accomplished by the electron transport system and ATP synthase (a) glycolysis (b) citric acid cycle (c) oxidative phosphorylation
Extending the Mechanism of Methylmalonyl-CoA Mutase to Similar Reactions Based on the mechanism for the methylmalonyl-CoA mutase (see problem 14), write reasonable mechanisms for the following reactions shown.
Figure 27.3 illustrates the response of R (ATP-regenerating) and U (ATP-utilizing) enzymes to energy charge. a. Would hexokinase be an R enzyme or a U enzyme? Would glutamine: PRPP amidotransferase, the second enzyme in purine biosynthesis, be an R enzyme or a U enzyme? b. If energy charge = 0.5: Is the activity of hexokinase high or low? Is ribose-5-P pyrophosphokinase activity high or low? c. If energy charge = 0.95: Is the activity of hexokinase high or low? Is ribose-5-P pyrophosphokinase activity high or low?
Understanding the Mechanism of Hemolytic Anemia Genetic defects in glycolytic enzymes can have serious consequences for humans For example, defects in the gene for pyruvate kinase can result in a condition known as hemolytic anemia. Consult a reference to learn about hemolytic anemia, and discuss why such genetic defects lead to this condition.