Term
| What is our major source of ATP and our major means of transferring energy from the chemical bonds of the fuels to cellular energy-requiring processes? |
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Definition
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Term
| What is used to generate ATP from ADP in oxidative phosphorylation? |
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Definition
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Term
| Tell me more about oxidation-reduction reaction... |
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Definition
| It always involve a pair of chemicals: an electron donor, which is oxidized in the reactions; and an electron acceptor,which is reduced in the reaction. |
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Term
| In metabolism, what is oxidized and what is reduced? |
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Definition
Oxidized- the fuel (glucose, fructose, etc.)
Reduced- NAD+ and FAD |
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Term
| What is the difference in reduction potentials of the oxidation–reduction pair? |
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Definition
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Term
| The bigger the E value the more... |
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Definition
| likely a molecule will be reduced or gain electrons |
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Term
| The more negative the E value... |
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Definition
| the less likely the molecule will be reduced, in fact it will be oxidized and lose electrons |
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Term
| What class of enzymes transfer electrons from the substrate to O2, which is reduced to water (H2O) or to hydrogen peroxide (H2O2)? |
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Definition
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Term
| What class of enzymes incorporate one or both of the atoms of oxygen into the organic substrate? |
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Definition
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Term
| Energy from fuel oxidation is converted to the high-energy phosphate bonds of adenosine triphosphate (ATP) by the process of... |
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Definition
| oxidative phosphorylation |
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Term
The electron-transport chain oxidizes _________
and donates the electrons to _____,which is reduced to _____. |
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Definition
oxidases NADH and FAD(2H)
O2 is reduced to H20 |
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Term
| What enzymes uses the energy from the reduction of 02 to phosphorylate ADP to ATP? |
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Definition
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Term
| How many mols of ATP per mol of NADH oxidized? |
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Definition
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Term
| How many mols of ATP per mol of FAD(2H) oxidized? |
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Definition
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Term
| What is a consequence of oxygen depravation from ischemia (low blood flow)? |
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Definition
| Inability to generate energy from the electron-transport chain results in increased permeability of this membrane and mitochondrial swelling. Mitochondrial swelling is a key element in the pathogenesis of irreversible cell injury leading to cell lysis and death (necrosis). |
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Term
What is the anthracycline drug doxorubicin used to treat?
What are some of the side effects? |
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Definition
1) It treats follicular-type non-Hodgkin’s lymphoma.
2) Its toxicity can impair the mitochondrial function. This is why dosing is key. It will possibly present as a patient developing biventricular heart failure.
To go more in depth...
Doxorubicin binds to cardiolipin, a lipid component of the inner membrane of mitochondria, where it might directly affect components of oxidative phosphorylation. Doxorubicin inhibits succinate oxidation, inactivates cytochrome oxidase, inter-acts with CoQ, adversely affects ion pumps, and inhibits ATP synthase, resulting in decreasedATP levels and mildly swollen mitochondria. It decreases the ability of the mitochondria to sequester Ca2+ and increases free radicals (highly reactive single-electron forms), leading to damage of the mitochondrial membrane. |
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Term
| From NADH, electrons are transferred sequentially through... |
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Definition
1) NADH Dehydrogenase (complex I)
2) coenzyme Q (CoQ)
3) cytochrome b-c1 complex (complex III)
4) cytochrome c
5) cytochrome c oxidase (complex IV) |
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Term
| From NADH, electrons are transferred sequentially through... |
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Definition
1) NADH Dehydrogenase (complex I)
2) coenzyme Q (CoQ)
3) cytochrome b-c1 complex (complex III)
4) cytochrome c
5) cytochrome c oxidase (complex IV) |
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Term
| Which enzymes are multi-subunit protein complexes that span the inner-mitochondrial membrane? |
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Definition
| NADH dehydrogenase, cytochrome b–c1 complex, and cytochrome c oxidase |
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Term
| What is a lipid-soluble quinone that is not protein-bound and is free to diffuse in the lipid membrane. It transports electrons from complex I to complex III and is an intrinsic part of the proton pump for each of these complexes? |
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Definition
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Term
| What is a small protein in the intermembrane space that transfers electrons from b-c1 complex to cytochrome oxidase? |
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Definition
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Term
| What is also called the proton motive force, it represents potential energy driving protons to return to the more negatively charged alkaline matrix? |
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Definition
| electrochemical potential |
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Term
| The headpiece of ATP synthase is found in? |
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Definition
| the matrix of the mitochondria |
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Term
| How many protons (H+) does it take to rotate the head piece of ATP synthase and how many ATP are made in result? |
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Definition
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Term
| What two important proteins are synthesized from the vitamin riboflavin? |
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Definition
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Term
| What is part of the TCA cycle and also a component of complex II of the electron-transport chain? |
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Definition
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Term
| Why do patients with anemia report symtoms of fatigue? |
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Definition
| The iron-containing cytochromes and Fe–S centers of the electron-transport chain in tissues such as skeletal muscle are affected as rapidly as hemoglobin and other iron containing proteins in the blood. A deficiency in iron will cause a decrease in production ATP-hence the fatigue. |
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Term
| Both hemoglobin and cytochromes contain heme group. What is one major difference about heme in both cases (think Fe)? |
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Definition
The iron atoms in the cytochromes are in the Fe3+
state. As they accept an electron,they are reduced to Fe2+. As they are reoxidized to Fe3+, the electrons pass to the next component of the electron-transport chain. Hemoglobin never wants iron to change its oxidation state. |
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Term
| What ions in the cytochrome oxidase complex facilitate the collection of the four electrons and the reduction of O2? |
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Definition
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Term
| What allows O2 to be “pulled”from the erythrocyte to myoglobin,and from myoglobin to cytochrome oxidase,where it is reduced to H2O? |
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Definition
| Cytochrome has a much lower Km for O2 than both myoglobin and hemoglobin. |
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Term
| Intravenous nitroprusside rapidly lowers elevated blood pressure through its direct vasodilating action. If a transfusion goes for too long 24 to 48 hours or more nitroprusside is converted to? |
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Definition
| Cyanide- inhibitor of the cytochrome c oxidase |
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Term
| How many protons are pumped at complex I (NADH Dehydrogenase)? |
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Definition
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Term
| How many protons are pumped at complex III (cytochrome b-c1 complex)? |
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Definition
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Term
| How many protons are pumped at complex IV ( cytochrome c oxidase)? |
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Definition
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