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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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
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biochemistry and related others by exploring similar questions and additional content below.Similar questions
- It is believed that the ratio of cyclic photophosphorylation to noncyclicphotophosphorylation changes in response to metabolic demands. Ineach of the following situations, would you expect the ratio to increase,decrease, or remain unchanged?(a) Chloroplasts carrying out both the Calvin cycle and the reduction ofnitrite (NO2-) to ammonia (This process does not require ATP.)(b) Chloroplasts carrying out not only the Calvin cycle but also extensiveactive transport(c) Chloroplasts using both the Calvin cycle and the C4 pathwayarrow_forwardA new ATP-producing protein is discovered that couples ATP production to the oxidation of NADPH by oxidative phosphorylation. Assume that the value of ΔGo for ATP synthesis is 30 kJ•mol−1. If this protein only produces 1 molecule of ATP per reaction that consumes one NADPH: a. How much free energy is wasted, under standard conditions?b. How many more ATP molecules could be created by a perfectly efficient electron transport chain from one NADPH?arrow_forwardThe reduction potentials of iron in each of the cytochromes in the electron transport complexesvary from 0.The reduction potentials of iron in each of the cytochromes in the electron transport complexes vary from 0.1 V to 0.39 V. Explain why these different values are necessary for the operation of this processarrow_forward
- Cyclic photophosphorylation uses two photons to generate one ATP. If the AG of ATP hydrolysis is -50 kj/mol. What is the percent efficiency of cyclic photophosphorylation? F =96.5 kj/mol*V. Use c AG = -nFAV ⒸShow Transcribed Text to solve.arrow_forwardEnzymes normally enhance the rates of biochemical reactions by preferentially binding and stabilizing the transition states rather than either the substrates or the products of a reaction. The F|-subunit of ATP synthase does not fit this norm so well as tight binding to ATP rather than a transition state is employed to make ATP. Explain the binding-change model of the mechanism of ATP-synthase. How and why is the proton-motive force used in the reaction cycle of ATP synthase?arrow_forwardUnder standard conditions, NADH reoxidation by the electron-transport chain has a free-energy change equal to –220 kJ/mol. With 100% efficiency, how many ATP could be synthesized under standard conditions? What is the "actual" efficiency given these numbers?arrow_forward
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