Exam3 - 11;“033200? 13215 FAX 5124?1B‘|35 BIDEHEH...

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Unformatted text preview: 11;“033200? 13215 FAX 5124?1B‘|35 BIDEHEH IIII'u' UT AUSTIN (II-1369 ExamThree November I. 2007 Name: all?) The following questions nro worth 1 pt ouch. «L Cm: Fran-Lou 4:059 34v C". I n r-wum n '- ME) 4 4t glycernld hydeua-F r. l. '7. - Fa. _ i, a thGDSLHWiL” ‘3‘} 2. I: Hf s M MAE-l yruinle ‘- (“Hi 11 l G I Lead-afie- glucose Mfl Mr W 2 glucose-fi-phos till: 5 Meir (- ' H 9~L phosphoonolpyruv‘gtm lflLgk-rp lntorrnediateCis olthmm AWL-"‘1- Pmpm'kt bump, A) glyderuldehyde-adphafiphntc 2.3 phosphogiyeernle B) 1.3 phosphoglyeernte @one of the above C) glyceroldoyde—Z-phosphnte Reactions 3 and ID generate ATP. "I J | D A) True also Which enzyme uses a Sehifi‘s b intermediate as part of the mechanism? A) enoinse El) hexokinase @ldolaee D) pyruvnte kinase B) glycernldehydo-B-phosphate dehydrogunnse is produood in renor‘ - 1 1 l. A) FADI-I E) NADl-I C) FAD @ AD" E) none ofthe above Which step generates the precursor for the silosterie regulator ot‘hemoglobin'i 2_, a (7 A113): c): DH E)5@6 on me up 1310 Which enzyme would be inhibited by reagents that react with snlfliydryl groups? - phosphoglueomutese D) melnte dehydrogennso lyeeraldehyde 3 phophate dehyrogenase A-u meg. T& 0:35 E.) ' uldolase CI-ketoglunrnte dehydrogennse ‘15 Lou gmuoX Intermediate 13 is A) fructos:—2.6-bisphosphate 13) LB phosphoglyeernle C) fructosofi-phosphnte D) 2.3 bisphosphogiycernle - fructosm I ephoaplmtc fructose-lfi-bisphoshate Intermediate A is A) fructose-1 -phosphate B) I.3 phosphogiyeernte C) fi'uclose—l,6—binphosphate D) 2,3 hisphosphoglyeeruto % glucose-i -phosphnte fructose-G-phoshate Version 1 ' + ELECTREINIE HESER 0023025 CA¢:.J‘/M’¢M '5 1: “L H ; fF/q'bhf-vz ‘ RH“H-n ..I_i_ : i 617'”: [#Tfl ._ 801 c._ i m hmmmhh CIA (“I-1's I": r______ . la, [4pr iifflfir’EUCI? 13:13 Fliii 5124?1|3135 BIDEHEH IIII's' UT AUSTIN + ELEETHEINIE HESEH 003r’025 MGM Use the diagram below to answer the Following qudsr'ns: ukbfi 1"!" a 9. is intermediate C -ketoglutarate El) succinyl CoA C) aeetyl CoA D) suceiltate E.) oxaloaeetate 10. Which reactions @thioester substrate? A’ ) Mag-lg. 1 A) 1.3 B) 1,4 1,5 DJ 1.3 E; 2.4 F) 2,5 6) none oi‘the above I 1. Which reactions generate NADI-l '? q 3; A) 1,3,7 13) 3,5,8 C) 1.4.8 33.8 E) nolte of the above are correct 3) J 12. What are the reactants and products For reaction 5'? A) citrate and ct—ketuglutnrate succinate and malate B) acetyl CoA and oxaloaeetate succinyl CoA and succinatc C) Dltniuflcett‘ltehndiaucitrntc P 13. Which reaction uses usueofuetor? IL Wayfirlwflm {I'll-i" 1 B -2 i " ~ o 7 H enl- trial-o v e. ‘ A) ) (3)3 as r)6 ) )3 'ab‘“ fipute 14. Which reaction is a hydration? #0113): (3):. [:04 E)5 me )7 HJB 15. Which ction uses a symmetrical molecule as a substrate? A)I@2 (1)3 D)4 E)5 16. Which reaction directly gene a high energy bond? A)lB)2 (3)313) F)6G)7 H)3 17. Which reactionsr (302‘? q A) 1,2 13) 2.3 ,4 D) 5.6 E) 7.3 17"; Mutiple Choice, 1 pt each 113. Avidin, a protein in can Whites. binds biotin very tightly and prevents its absorption in the intestine. Consumption ot‘large amounts ol'ruw eggs can result in a biotin deficiency. Which of the following metabolic conversions cannot occur without biotin? (Note: This is not a problem with cooked eggs because cooking denatures avidinJ A) Oxaloacetate -+ phosphoenolpyruvate @ Pyruvate —> oxaloacerate 13) 1,3~Bisphosphoglyccratc —t glyceraldeltyde-El-phosphttte ) Phosphocnolpyruvnte -> 2-phosphoglyeerate C) Fructose-1,6-bisphosphate —h fructose-fi-phosphate 19. The two main purposes ofthe citric acid cycle are: synthesis of citrate and gluconcogencsis. degradation of acetyl-CoA to produce energy and to supply precursors for anabolism. ) degradation ofpyruvate to produce energy and to supply precursors for anabolisrn. D) degradation of glucose to produce energy and to supply precursors tbr anubolisn-i. E) degradation of pyruvate to produce energy and to synthesize oxaloacetate for glueoneogenesis 20. Geminating plant seeds can convert acetyl-CoA (obtained from fatty acids stored as oils) into carbohydrates. whereas animals are incapable of converting fatty acids into glucose. This difference is due to the that that: ' animals have glycogen and don't need to make glucose from fatty acids. .3, plants use the elyoxyiate cycle to convert two acetyl CoA to oxaloaeetate, a precursor for glueoneogenesis. Animals do not have this eyele plant seeds use photosynthesis to make sugar. D) animals use due citric acid cycle exclusively for energy production, whereas plants do not require much energy and just use glycolysis. m C&D 21, Cytnsulic NADH is directly transported into the matrix to deliver its electrons to the electron transport system, True @alsc Version | Page 2 lifflEr’EUCI? 13213 FAX 5124?1|3135 BIDEHEl-l DI'v' UT AUSTIN + ELEETHEINIE HEEEH 004f025 _ H-l ll decimal-4"“ True False 22¢ Q cycle requires 2 ubiquinone molecules to move 2 electrons. it“ch I: l 5 l1 3 r 11.5. I r - 23. How many - ten: are pumped by compch W for every one cytochrome c? h 0"! "locum" C’ ca" "L 4,5 M F' 9 l 1' If A) none ne C) two [3) four E) none of the above _ , pram [limiter/4:31- ptfiv l b1 24. Place the following in order of‘ standard tedex potentials, with the most negative first. 1. NAD+MADH 2. Daft-Iii) 3. succinnteialpna-ltetoglutarate d. cytochrom c (osycyteehrc ed) A) 1-2-34 El) 1-3—4-2 1-4-2 D) 2-3-4-1 E) 3—4-1-2 25. A major allosteric regulator ofboth glycolysis and glueoneogenesis is: A) 2,3 bisphosphoglycerate D) fructose |.6 bisphosphatc 1,3 bisphosphoglyeerate E) nane ol‘the above fructose 2,6 bisphosphate 26. The electrons formed From the complete oxidation ofglucose are: directly transferred to 0: during the citric acid cycle. D) A and B trans Fer-red to the coenzymes NAD"‘ and FAD. E) none of‘ the above C) transferred to succinct: and nrnchidonic acid. 27. The reaction mechanism catalyzed by giycernldeh 3-phosphatc dehydrogonase involves all ol‘thc following except: A) C0valcnt catalysis l3) Inorganic phosphate Pyrephosphate D) 1,3 bisphosphoglycerate E) NAD‘" 28. Which ol‘the t'ellowin 'actors do not contain an adenine; A) CoA E) NADl' MN D) FAD E) Allofthese contain adenine 29. Lipoic acid was discovered by i A) Hans Krebs B) Peter Mitchell C) James Watson ester Reed E) None of the above ' 30. A reaction that r lenishcs the intermediates ol‘a metabolic pathway is start reaction . A) exergouic anaplerotic C) endergonic D) amphibolio E) none ofthe above 31. 'ch of the following are important in regulating isocitrate dehydrogenase'i‘ F‘ ".4 3 @Aor a) are C) NAB" o) AcctthoA a) an et‘the above '3“ ‘5 32. The pentosc-phosphete pathway is used to produce which of the l‘ollowin cules'i A) NADPi-i B) Pyruvate C) Ribose-S-phosphate D) oxaioacetate andC F) B andD 33. Which of the t‘ollouring statements about glycogen is false? A) Glycogen is a polymer ol'glucose in ecu-+4) linkages with inn—>6) linked branches every 3—12 residues. Glycogen is the storage polysaccharide in skeletal muscle and liver cells. % UDP—glucesc is produced fi'om glycogen by the action of the enzyme phosphorylasc. in glycogen breakdown. glucose residues are sequentially removed from the nonredueing ends. E) The breakdOWn of' glycogen in skeletal muscle ultimately supplies glucose-fi-phosphate, which can enter glycolysls to generate ATP. 34. The Q cycle is yclic flow of electrons involving a ubiquinone lntennodiate(s) to Complex ofthe mitochondrial electron transport chain. A) I E) I] II D) W E) none of the above 35. Which of the following are possible sources of acetyl C - ‘r the TCA cycle? A) Amine Heidi: B) Fatty acids C) Carbohydrates lofthe above 36. Oxidative phosphorylction is regulated by: A) the availability of'rcduced cof'actora From catabolie pathways. A and C B) the availability of die dN'l‘Fs. A. B. and C C) the availability of ADP and Pr. 3?. What is this molecule? ILL t t t t . tit“ it Hs--L‘Il ml, :1 t' - -( ll- lll_ L' ---L‘ii -- rl' -L||.---l'_|—||l "in-g --tJ-—t‘l-l, m \- w. (w ill. [19 r_)E' If “‘4, H 3n .i-r) on A) FAD s) biotin C) NAD+ o) lipoic acid a) TPP®20A Version I l'age3 HICISIEUCIT 13:13 Filii 512dT18135 ElIEIEHEi-‘I IIII'Ii' UT AUSTIN + ELEETHEINIE HESER 0053’025 38. Which is the net equation ot‘glycolysis as it occurs in aerobic cells such as brain cells? A Crlucose + 2 ATP —s 2 lactate -I- 2 ADP + 2 Pi @Glucosc -I- 2 ADP + 2 Pt + 2 NAD' —s 2 pyruvate + 2 ATP + 2 NADH ) Glucose + 2 ADP + 2 P1 —> 2 lactate -i- 2 ATP D} Glucose + 2 ADP + 2 P; —> 2 CHJCHtOl-l + 2 CD: + 2 ATP E) Glucose + 2 ADP + 2 P: + 2 NAD*-+ 2 lactate + 2 ATP + 2 NADt-l 39. The same two aeetyl carbons that enter each round of the citric acid cycle are immediately released as two molecules oi‘curbon dioxide in the same round. True @fllfl #0. in which at“ the l‘ollowing metabolic corwersions ls ATP "consented" during glyeelysis? ' l.3-Eisphosphoglycerate —i- 3-phosphoglycerate lucosc -+ glucose-o-phosphate C) 2-Phosphoglyccratc —s 3-phosphoglyceratc D) FructOSU-i.G-hisphusphale —r dihydroxyacctone phosphate + glyceraldchydc-S-phospltate E) Glucose-d-phosphate —i- tl'ttctose-6~phosphate 41. ATP synthase active sites: A) l a) 2 o) 4 a) s ' It. The following questions are each worth 2 pts. “7 with“ I.) FANJ-L -" 41 Which are the mobile carriers ofeleetrons in metabolism? A) NADH. FADHa, Cle-h, cytochrome c D) 'I'N'ADHI CoQHt, cytochrome c B) NADH. FADH2. CoQHz, CoQi—la. cytochrome c C) FADl-li. Cle—Iz. cytochrome c 43. Which ot‘ the following are true statements about the structure of ATP syntl‘tasc'.’ A) It has a membrane-embedded component called Ft) and a component found in the matrix referred to as FL 13) The 7 subunit acts as a turn shalt in the rotational motor. C) The structure has a "lollipop" shape. A and E A. 13. and C 44. The functional core oi“ Complex 111 includes: A) cytochrome en. iron-sulfur protein (Rieslte protein) cytochrome t:|. cytochrome b, myoglobin. _ _ , - =. t' b cytochromec t cytochrome b, tron-sulfur rotein Rteske totem a?) | p ( P l (3 L1 mu trieifldfl. 5 D) all or‘ the above E) none of the above N‘D arr G: Cmntd'tcL 7. 2.0 45. What is the yield of ATP fl'om the complete oxidation (glycolysia, citric acid cycle and electron transport) ofhlycerol 3 phosphate'iilttssume 3 ATP/NADH and 2 ATPfFADI-la a GTP-ATP. P A) s a) 12 C) 14 o) 16 20 F) mine ot‘rhe above “- 4 DL M 46. The diagram represents a “substrate cycle" or “fistile cycle" in glucose metabolism. Which ot‘the following statemean about the cycle is cut-rent? A) Root-titans till ii are catalyzed by the same enzyme and help establish an equilibrium between the two metabolites. Reaction ll produces ATP by substrate-level phosphorylation. @ Reaction l is catalyzed by an allosteric enzyme that is activated by froetose-2-6-bisphosphate_ Reaction l is involved in die biosyntheais ot'glueoae. E) Reaction ll occurs under low-energy conditions when the cell needs ATP. 47. Eiesynthesis requires the expenditure of free energy. Which of the following metabolic conversitms involved in glucose synthesis requires the direct expenditure of ATP Free energy (ATP is also a reactant)? A) Glyceraldehydc-S-phosphate + dihydroxyacc'tonc phosphate —> fructose-[,6-bisphosphate Fl'tlctose- I ,fi-biaphoaphntc —> i'iru ctosc-fi-phosphntc @ 3-Phosphoglyccratc —s 1,3-bisphosphoglycerate l,3~Bisphoanhoglyeeratc —r glyceroldehyde-Ii-phosphute E) None oi‘Lhe above. Version 1 Page 4 113053200? 1321? Hill 5124T1|3135 BIDEHEl-l IIII'u' UT AUSTIN + ELEETHEINIE HEEEH 008.3025 45. Place the following events in the citrate synthasc reaction in the correct order: i. ucetyl cola enters active site ii. oxaloacetate actors active site iii. citrate is released A o '— C, CASDFL (LOW E. iv. water enters the active site for hydrolysis v. citroyl cost is made vi. an cool is generated ii-i-viuv-iv-iii l3) ii-i-iv-iii-vi-v @4-vi-wiv-iii D) i-ii-ivuiii-vi-v B) none are the correct order 49. Which statement is correct concerning the metabolic reaction shown below? HOEH; .anm H1 ..—__ H l I H he enzyme that catalyzes this reaction is called a mutase. = The enzyme that catalyzes this reaction can be classified as a ltinase. C) This reaction requires the free energy ot‘ATP hydrolysis. D) This reaction occurs only in the kidney. E) The oxidation level of glucose-l-phosphate is higher than that of glucose-G-phosphate. 50. (l 0-3a) The brain uses 40% of the circulating glucose under normal circumstances. in the brain, the first step of glycolysis is limiting compared to muscle tissues and liver in which step 3 is limitng. The brain lacks the ability to store energy in the form of glycogen and therefore relies upon glueoae ot glucose-l-phosphate t'or glycolysis making the first step ol'glycolysis limiting. rue I: False RAH-p an 5 |. What would be the predicted energy yield ol‘itt'l'l:I From glyeoiysis in a patient with a defect in trioscp as are isomernse? @OATP a) IATP C)2ATP mam: E)4ATP mm 6.3;. o nel-A-"TP .52. (1 1-93) The compound S—acetonyl-CoA can be synthesized from l-bromoacetone and eoenzyme A. The Lineweaver—Burk plot of the inhibition of citrate synthase by S-acetonylaCoA is” spawn. What typeofinhibitorisfifeetonyl-Com 0 || i-roc— c— c: l-_.---‘ s em am 41 ‘l D DE B one mi iN'-At:t':ltiIItg.'l-(_'.UA manuscuAHHM-Ii I I A) irreversible B) non-competitive ompetitive D) it is not an inhibitor 53. The isomerization of‘eitrate to isoeitrate: A) is the only unnecessary step ol‘ the citric acid cycle. protects cells from the toxic effects ofarsenite ion. @eoawr‘ts a tertiary alcohol. which cannot easily be oxidized. to a secondary alcohol that can be oxidised. is a major regulatory step for the citric acid cycle. E) is an oxidation reaction. 54. Which ol‘the Following statements are true about oxidative phosphorylation? A) Electron transport provides energy to pump protons into the interrnembrane space. E) An electrochemical gradient is formed across the inner mitochondrial membrane, Potassium and sodium ions form an ionic gradient across the inner mitochondrial membrane. @ A and B . B and C F) A, a, and c 55. Place the following events in the enzyme mechanism for aldolase in the correct order: i. active site lysine forms Schil’l‘s base ii. tyrosine gives up proton forms Sehiff‘s base iii.aubtllratc binds to active site iv. hydrolysis of Sehifl's base v. tyrosine accepts proton and bond breaks in s a . ‘ . A) ili,ii,v,i,iv El) ill.iV.V.li.l C) iii.v.iv,ii,v iii,i,v,ii,iv E.) iii,i,iv,ii,v Version 1 Page 5 llr’CIEiIEUCIT 1321? FAX 512|1T18135 ElIEIEHEl-‘I [II'v' UT AUSTIN + ELEETHEINIE HESER WWQEE 56. Several prosthetic groups act as redox centers in Complex 1, including; A . FM'N, ubiquinone. iron-sulfur clusters. heme. D) all of the above ‘3” FMN. ubiquinone, iron—sulfur clustersr E) none of the above heme, ubiquinone. iron-sulfur clusters. 57. Which of the following statements about glycogen and glucose metabolism in skeletal muscle is correct? Glycogen is hydrolyzed to Free glucose that can then enter the glycolytic pathway. @Glucose residues from glycogen yield a net of 3 ATP when converted to lactate in skeletal muscle. No nucleotide is required to convett glucose to glycogen D) A reducing end is Ihe only site to degrade glycogen lo glucose-fi-phosphate. E) ATP is directly required for the conversion of glycogen to glucose-l-phosphnte_ 58. Which ot‘thc regions circled below is the correct functional part of this eo—factor‘? B 0 fl) ll A l- CH1“ CHE—o --l-'—(_) —P-—o@ l i C‘I ‘53 l «I - DE, 09 F N/ l - 11—NQS H®N H C D A) l3) @ D) E) Nora: ol‘tho above 59. Glucose-fi-phosphnte is a substrate/product in which of the following or at? - s‘i‘ A) Gluconeogenesis El) Glycolysis C) Pentose phosphate pathway a ll of the above 60. One reason why arsenic is poisonous is that arsenite ion (A5033) reacts with reduced lipoamide to fotm a stable complex as shown. This derivatch of , “POEM”: t-‘ilflflDl lJ= Tflolldizcd- Wltlelt Dllll'Ie FolloWintt metabolic conversions cannot occur in the presence ol'untonite? | 0 ‘ Lyn l WNPW S S \Jié: o. A) Pyruvate + C0; -+ oxaloacetate. ' Phosphoenolpyruvgtc + CD; —+ oxaioacetate B) Pyruvntc —t- ncetyI-CoA-I- (30:. F‘Fbc- Curh'p $13 “'1‘”: C) o-Keloglularete —> suecinyl-CoA+ (30:. AandD 61. What is Lhe Function of this molecule? if C _ :i 4‘ M |-|N/ KNil %L .1}: a“ - --— H I \ {fit-l Hut,“ #CI-t—CHI—CHN—CI-h—(311,—: q ' ' ‘ ‘x " Clll A) electron transport to complex] D) electron trans on within con-t lcxl P P electron transport fi'oln complex l to complex II E) acetyl group transfer urboxylation F) none of the above 62.. Which of the following is correct concerning the metabolic reaction shown below? Pyruvate + NM)" + Con-EH —t- Aeetyl-CoA + NADH + H- + (:0; A) The enzyme that catalyzes this reaction contains u biotin group. B) This reaction is sometimes referred to as on maplerotic reaction in that it “refills” the citric acid cycle when intermediates have been removed for biosynthcsis. C The enzyme that catalyzes this metabolic conversion is activated by high concentrations of ATP, @This reaction is an oxidative dccarboxylution. This reaction is catalyzed by an enzyme in the cytosol of the cell. Version 1 Page 5 lifflEr’EUCI? 13:1? Fitii 5124?1|3135 BIDEHEl-l DIl'iI UT AUSTIN + ELEETHEINIE HESEH 003.3025 63. Which ot‘dte regions eirelcd bclmv is the correct Functional part of this molecule: D M f') 3 pt each 54- (12-35) In MifiCifll Sriilflmfl. thc Fl: OfATP syntliasc can be inserted into an artificial rncmbranc and functions as a proton channel. The proton channel activity is blocked when the F. component is added to the artificial n'IcmlJrane. Based on your knowledge ol‘the ATP wattage mechanism you add d find it restores the proton channel activity. ,1) :3 Lu wares; “4% ‘ A) ADP 5W C) Pi D) PFI E) none ofthe above M A I 65. (l 0-30) A Metabolic discnac caused by the lack ol'glucosc-fi-phosphatese reatilts in symptoms that include cnlnrgement aI’llVer, What is the cause arm: Enlarged liver? fit increased production cf'pyruvctc results in pH induced edema incrcuscd production ol‘glycogen due to build up ot’glueese—l-phcsphatc increasecl production of livcr glycolytic enzymes D) A and E E) a and C F) none ol‘the uhov: 66. (l l-23) You are studying the chchs of'cxcrcisc on Inusclcs using a rat model. You measure the level of‘ pyruvatc. oxnloacctatc and phosphoenolpyruvate before and after cxcrcisc. You find that the level of pyruvate is constant, oxaioaeetate increases and phosplmcnulpymvate is decreased You expected that the levels of both phosphocnolpymvatc and pyruvate would dro due to increased glycolysia and entry into the citric acid cycle of the pyruvute, chcvmclnbcr that pyruvntc can also be used to maitl would account for the increased level of ostalcaeetute. is this correct? A ‘r'e‘fii! . i ' ) (“Par UVan Hit); h—g we: LhDQU—FLCF-"LL' 67. ( [0-14) Arsenatc is a phosphate analog and can replace phosphate in the glyceraldehyde 3-1“I dchydrogcnasc reaction. What would be the expected effect ‘ . "‘1‘ ATP yield in glycolyais in tho presence Dl'arsrennlc? wi ATP produccd B) 1 ATP produced C‘.) 2 ATP produced D) 3 ATP produced E) 4 ATP produced used to prepare mitochondria. Thc ratc cl'oxygcn cgpsurnpti was-measured in the presence ni‘s oxygen was then measured in the presence of pyLu'vamfmalate +,7- I wwwmflr i i- ‘ . i was also found to below. m..- _._ i ' ' Eascd on these data you conclude that your patient has a defect in A) Complex] l5) Cornplcx II C) Complexlll D) Complex IV FBI-[complex Version 1 Page 7 11IOElr’200? 13:13 Filii 5124?‘|B‘|35 BIDDHEl-‘I DI't' UT AUSTIN + ELECTRDNIE HESER 0033025 _ —-.,-u-...-. hen-nu ; 1. ts. was born after a 34—week gestation period. In the first 24 hours‘df life he littlopcd respiratory distress. At 3 weeks, hr.- beeame dependent on a ventilator iilllCll he t'equ1red tor the rest of his life. By 6 weeks, he had developed neurological problems. A heart murmur was observed. and tests revealed a erirdioinyopalliiil Between 5 and 16 weeks, he developed progressive lacticacidemia (an increasedutit' of lactate to pyruvatc in the blood) and an elevation of serum pyraVate. The hell i‘ : cacidernia persisted until the child died ol‘cerdiopulmonary arrest at 16 weeks ofagti Tail-l5 Performed on the infant shoWed normal levels of glycolytic and glass ii neogenic enzymes. Pyruvate dehydrogenase activity was also normal. 1: After the infant's death. mitochondria were prepared from his heart. The tutti! _j oxygen consumption by these mitochondria was measared with snccinate as a salt strate. It was normal, both in the presence and absence of ADP. When the mitochon- dria were incubated with pyruvate plus malate, however, the rate of oxygen Cliil- sumption was extremely low. It was still far below normal when ADP was addtt '-. Electron paramagnetic resonance (EPR) measurements showed a lower than l‘lOl'IlTllé content of iron, and were able to pinpoint the complex and type of iron invohietl. Succinate was oxidized normally by mitochondria isolated from the infant’s heat but pyruvste was not. Therefore, the problem was not between snccinate and Tllctlll of the electron transport chain, but in the NADH dehydrogenasc complex (Complti 6 1). Because the iron content of his mitochondria was low, the problem was rnonlitt- RM ly in an Fe—S center in Complex I. (This complex does not contain a cytoctu‘ontdfllt / problem' in Complex I caused NADI-IfNADi' to increase, which resulted in an lillllllii tion of pyruvate dehydrogenase. the accumulation of pyruvate. and its conversitmli lactate. Consecuentlv. dae levels of rwnwnte: and lactate increased in the blood Decreased oxidation of NADH . and FADiEH) in the ET chain . results in pyruvste s... lactate GIUGDBB and fatty acids —- triglyceride NAD“ Fatty acids NADH Pyrwate I Glycerol—P LDH NADH Triglycerid Fatty acyl cernltine NAD“ Pyruvate Acetyl CoA Lactate Fatty acyl CoA NADH, FAD(2H) Deficiencies or inhibition of TCA cycle enzymes (nuclear encoded) Inhibit acetyl CoA oxidation Cytochrome Cytochmme oxidese b—c. Complex IV Complex III Cu. Fe Anoxie. lschemie. cyanide. i220 poisoning and other interruptions of the ET chain prevent electron r flow and ATP synthesis Genetic defects in proteins encoded by mtDNA (some subunits of Complexes I, III, IV and F0F1—ATPase) dcreaee electron transport and ATP synthesis Dysfunctional mitochondria. Genetic deficiencies or other the blood, and incorporation of fart . , , _ , , I I acids into trirl c r'des t' - at problems in oxidative metabolism result in accumulation of lactate in glycerols). ET = electron transport. y E y e 1 ( mm“ HEWIEUCIT 18211 FAX 5120318135 BIDEHEH IIII'u' UT AUSTIN + ELEETHEINIE HESER 0023’002 Answer Key ._ PFFHQPPPFH Mb...—.—.__._—._-._.._. rpwwflgwéwwr MMMb-lld HF‘HPE-‘J. gififiififififiigfifififififfifififigfig 5 UOEEUJ'HUUOOFUZbE'UE-JOWOOWI'WWWUOMWOUEUD>fiT|mTiUGWETJ Lnb'l .Nr'. LnLfl +w mmmmammuum 9¥FPTPFDFETJP. an F" cn Ln 7.. Ln >>EEIDJDJUUDUIUDMEUUOD>>>OODUOW an 9': Version I Puma ...
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This test prep was uploaded on 03/19/2008 for the course CH 369 taught by Professor Kbrowning during the Fall '07 term at University of Texas at Austin.

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Exam3 - 11;“033200? 13215 FAX 5124?1B‘|35 BIDEHEH...

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