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There is a fixed number of NADH and FADH2 produced per glucose oxidizes (assuming we are starting from the beginning of glycolysis) so reason 2 is unimportant for variability. The third reason you are right that the cell uses the proton gradient for additional purposes such as pumping ADP and Pi into the mitochondria by secondary active transport but we know ...


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It depends on the mode of transport used to transfer reduction equivalent (NADH or FADH2) across the inner mitochondrial membrane. If glycerol phosphate shuttle transfers hydrogen atoms across the membrane, it uses FADH2 and 3 ATPs are produced. And in case of malate-aspartate shuttle NADH is used for transport and 5ATPs are synthesized. Each FADH2 ...


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You are totally spot on with #1. ADP phosphorylation pump is driven by the proton gradient and ADP availability, while the the electron transport chain slows when it becomes too hard to pump protons. Furthermore, other processes (mostly channels) may use up a proton from the gradient. The different electron carriers have store different amounts of energy (...


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Radical generator Looking at the molecules they are highly conjugated —must be dark red or similar! And the disease is photosensitivity. Aromatics + UV? That is a standard UV radical reaction. It may be enough as a catalyst, but you'll get more will a cyclic amine, such as pyrrolidine or piperidine. If you want to go technical confer: Hofmann–Löffler ...


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They have complimentary interfaces on their surfaces and it is energetically favourable for them to stay together once they have found each other by Brownian motion. Often they are highly unstable alone. So it is simply thermodynamics and a decrease in Gibbs free energy. This happens across life. Enzyme complexes in bacteria are on the same operon, ...


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If a molecule is polar, it has a relative charge within the molecule. That is what polar means. For example ethanol. https://employees.csbsju.edu/hjakubowski/classes/Chem%20and%20Society/Alcohol_Drugs/olEtOHStructAct.htm The formal charge on each atom in ethanol is zero. This is calculated by assigning electrons to each atom in ethanol and ...


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The two most often used methods used to determine protein structures are X-Ray crystallography and NMR (nuclear magnetic resonance spectroscopy). Both of these allow some deductions of electron configuration, but don't actually measure it directly (and as far as I know there is no method available that can do that, but physicists might know more about that). ...


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As far as I am aware, there is no known requirement for Cd in mammalian systems, but it is extremely toxic (Waalkes & Goering). It would seem that cadmium is required to get crystals of RBP, and its presence is an artifact of the crystallization process (ref): Pig holoRBP crystals were obtained at 277 K by the sitting-drop vapor- diffusion method, ...


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Acetyl-CoA has three carbon-hydrogen and one carbon-carbon bond, and it is electrons 'held' in these bonds that are available for biological oxidation. Thus we say that acetyl-CoA contributes four reducing equivalents. In the TCA cycle, these are transiently passed to NAD+ (to give NADH) and to FAD (to give FADH2): the cofactors may be considered ...


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