Biochemistry
6th Edition
ISBN: 9781305577206
Author: Reginald H. Garrett, Charles M. Grisham
Publisher: Cengage Learning
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Chapter 21, Problem 5P
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+.)
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In cyclic photophosphorylation, it is estimated that two electrons must bepassed through the cycle to pump enough protons to generate one ATP.Assuming that the ∆G for hydrolysis of ATP under conditions existing inthe chloroplast is about -50 kJ/mol, what is the corresponding percent efficiency of cyclic photophosphorylation, using light of 700 nm?
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Chapter 21 Solutions
Biochemistry
Ch. 21 - P700* Has the Most Negative Standard Reduction...Ch. 21 - Prob. 2PCh. 21 - Prob. 3PCh. 21 - Prob. 4PCh. 21 - The Relative Efficiency of ATP Synthesis in...Ch. 21 - pH and in the Chloroplast Proton-Motive Force...Ch. 21 - Prob. 7PCh. 21 - Prob. 8PCh. 21 - Prob. 9PCh. 21 - Prob. 10P
Ch. 21 - Tracing the Fate of CO2 During Photosynthesis...Ch. 21 - Prob. 12PCh. 21 - Prob. 13PCh. 21 - The Source of the Oxygen Atoms in Photosynthetic...Ch. 21 - Prob. 15PCh. 21 - Prob. 16PCh. 21 - Prob. 17PCh. 21 - The Overall Free Energy Change for Photosynthetic...Ch. 21 - Prob. 19PCh. 21 - Prob. 20PCh. 21 - Prob. 21P
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