Concept explainers
(a)
Interpretation:
The number of ATP equivalents consumed per N atom of ammonium formed needs to be determined.
Concept Introduction :
A molecule of GTP has a quantity of energy needed in its triphosphate cluster that is corresponding to the quantity of energy in the triphosphate cluster of a molecule of adenosine triphosphate. Those molecules have identical quantity of energy; however, they are not equivalent molecules.
(b)
Interpretation:
The nitrogen fixation pathway needs to be explained.
Concept Introduction :
Nitrogen fixation could be a method by that the nitrogen atom within the air is reborn into ammonia (NH3) or diazotrophs; the nitrogen’s-generated ammonia is assimilated into salt through the aminoalkanoic acid synthetase/glutamate synthase pathway.
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Biochemistry
- The Energetic Cost of Nitrogen Excretion via the Urea Cycle How many ATP equivalents are consumed in the production of 1 equivalent of urea by the urea cycle?arrow_forwardNitrogen fixation is the reaction of: conversion of gaseous N2 into a biologically useful form of nitrogen (NH3). conversion of gaseous NH3 into a biologically useful form of nitrogen (N2). reduction of nitrogen to a peptide bond. fixing gaseous N2 into an unreactive form. electron transfer to ATP.arrow_forwardAmong the given choices, a. FAD, b. NADPH, c. NADH, d. FADH2, which of these is the form of reducing equivalent is required for fatty acids in biosynthesisarrow_forward
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- From the complete oxidation of glucose (glucose → 6CO2), how many total NADH electron carriers are produced and how many total nucleotide triphosphates are yielded (be sure to deduct payback) as part of substrate level phosphorylation?arrow_forwardBoth the yeast Saccharomyces cerevisiae and the bacterium Zymomonas mobilis produce ethanol from glucose under anaerobic conditions without external electron acceptors. The yield of cell biomass from glucose is 150 mg/g for yeast and 75 mg/g for Z. mobilis. In both cases, the nitrogen source is ammonia (NH3) and both cellular compositions are represented by the formula CH1,8O0,5N0,2. (a) What is the yield of ethanol from glucose in both cases? (b) Based on the results of part (a), which microorganism seems most efficient for the production of industrial ethanol?arrow_forwardThe 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+.)arrow_forward
- In the beta oxidation of linoleic acid, converting the 3, 5, 8 trienoyl CoA intermediate back to an expected intermediate for a beta oxidation substrate costs the equivalent of how many ATPs? (hint: look at the 'right side' of the figure for addressing problem 3 with linoleic acid)arrow_forwardAll of the following products of biosynthesis are nitrogen-rich tetrapyrrole structures that can be synthesized from Krebs cycle intermediates (in some plants, animals, or bacteria), with the exception of: triglyceride molecules chlorophyll b molecules vitamin B12 molecules chlorophyll a molecules heme molecules Identify the Krebs cycle enzyme that consumes a six-carbon substrate molecule, producing a five-carbon product molecule along with NADH, and one molecule of CO2. succinyl CoA synthetase a-ketoglutarate dehydrogenase malate dehydrogenase isocitrate dehydrogenase citrate synthasearrow_forwardWhy must nitrogen fixation occur in an anoxic (i.e., oxygen-free) environment? a)Because H2 is an additional product of nitrogen fixation, and the combination of H2 and O2 would cause the cell to combust. b)Oxygen poisons the dinitrogenase enzyme by entering the FeMo cluster c)Oxygen competes as an electron acceptor in the ETC, so electrons cannot be passed to N2. d)Oxygen "steals" electrons from the dinitrogenase reductase, producing free radicals.arrow_forward
- BiochemistryBiochemistryISBN:9781305577206Author:Reginald H. Garrett, Charles M. GrishamPublisher:Cengage Learning