Term
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Definition
-occurs in all tissues that have mitochondria and oxygen
-set of 5 immobile protein complexes embedded in mitochondrial membrane (1-4 part of ETC)
-mobile carriers-CoQ and cytochrome c |
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Term
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Definition
-reduction of complex I or II
-substrates-NADH and FADH2
-complex I-NADH dehydrogenase
-NADH oxidized to NAD+ by reducing FMN to FMNH2
-complex II-succinate dehydrogenase
-FADH2 oxidized to FAD by reducing succinate to fumarate |
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Term
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Definition
-electrons transferred from CI or CII to CoQ
-CoQ becomes CoQH2 |
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Term
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Definition
-electrons transferred from CoQH2 to CIII (cytochrome bc1)
-Fe carriers electrons
-Fe+3 reduced to Fe +2 |
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Term
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Definition
-electrons transferred from Fe+2 to Fe+3 in cytochrome c
-outer face of inner mitochondrial membrane |
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Term
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Definition
-electrons transferred from Fe+2 in cytochrome c to Fe+3 in complex IV
-enzyme-cytochrome c oxidase |
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Term
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Definition
-transfer of electrons to oxygen
-complex IV has an O2 binding site
-transported electrons,free protons, and O2 reduce to form H2O |
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Term
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Definition
| -explains how free energy generated by ETC is used to produce ATP |
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Term
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Definition
-free E from electron flow in ETC is coupled to pumping protons across the inner mitochondrial membrane
-from matrix to intermembrane space
-takes place in CI-CIV
-creates electrical and pH gradient
-E generated by gradient is common intermediate between oxidation and phosphorylation |
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Term
| How does ETC produce ATP? |
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Definition
-ATP synthase (complex V)
-hypothesis-protons pumped into intermembrane space re-enter the matrix thru a channel in the F0 domain of CV, driving the rotation of F0
-rotation of F0 causes conformational change in F1 that allows binding of ADP and Pi and produces ATP |
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Term
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Definition
-each NADH that goes thru ETC generates 3 ATP
-each FADH2 generates 2 ATP |
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Term
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Definition
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Term
| reactive oxygen species/free radicals |
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Definition
-superoxide:O2*
-hydrogen peroxide-H2O2
-hydroxyl radical-OH*
-can cause oxidative damage |
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Term
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Definition
when rate of ROS generation exceeds the breakdown
-characteristic of many inflammatory diseases (lupus,diabetes)
-normal aging thought to be partially caused by accumulation of ROS induced damage |
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Term
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Definition
-repair damage
-antioxidant vitamins ACE
-ROS-detoxifying enzymes-superoxide demutase (SOD)
-catalase (CAT)
-glutathione peroxidase (GPx) |
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Term
| beneficial effects of ROS (low levels) |
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Definition
-regulation of NO intracellular signaling
-bactericidal activity of macrophages
-substrates for certain enzymes
-maybe in signaling pathways |
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