Chem 153 A Fall - 2005 FINAL EXAM - I It Seat ‘ i...

Info icon This preview shows pages 1–13. Sign up to view the full content.

View Full Document Right Arrow Icon
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 4
Image of page 5

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 6
Image of page 7

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 8
Image of page 9

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 10
Image of page 11

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 12
Image of page 13
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: I It Seat ‘. i . Chemistry 153A Fall 2005 Final Exam 14 Number itTA's name Time and clay of your discussion section INSTRUCTIONS YOU SHOULD HAVE ONLY YOUR STAMPS, WRITING MATERIALS, ERASER, APPROVED NON-PROGRAMMABLE, NON-GRAPHING CALCULATOR WITHOUT CASE OR COVER AND YOUR PICTURE I.D. ZIP EVERYTHING ELSE INSIDE YOUR BACKPACK AND STORE IT ALL THE WAY UNDER YOU CHAIR. p... 00 O __ I3 .r E II U3 I.—- U.) [0 U1 II y—I --..‘l Lu [\3 Hi NO OTHER ELECTRONIC DEVICES OR CELL PHONES ARE ALLOWED. NO BOOKS OR LOOSE PAPERS OF ANY KIND SHOULD BE IN THE VICINITY OF YOUR DESK. II 1+) N WRITE YOUR SEAT # AND INITIAL (1“ letter of your last name) IN THE UPPER RIGHT-HAND CORNER. FILL IN THE INFORMATION ABOVE AND YOUR LAST NAME IN THE SPACE PROVIDED ON EVERY PAGE OF THE EXAM. SIGN BELOW AFTER READING ALL INSTRUCTIONS. READ EACH QUESTION CAREFULLY! BUDGET YOUR TIME. SHOW YOUR CALCULATIONS! KN -—-* o ._C “9 E U\ W N ,_. [\J I... ._I Li) A... TOTAL 300 NO CREDIT WILL BE GIVEN FOR ANYTHING WRITTEN ON THE BACK OF A PAGE OR IN A SPACE OTHER THAN THAT PROVIDED FOR YOUR ANSWER. TOTAL COURSE SCORE ANSWERS MUST BE BRIEF AND TO THE POINT. WHERE WORD LIMITS ARE SHOWN, No CREDIT WILL BE GIVEN FOR THE PART OF YOUR ANSWER THAT SIGNIFICANTLY EXCEEDS THAT ‘ LIMIT. FINAL COURSE GRADE Numbers in parentheses represent the point values. Some useful values: I h d d d l . . . AGO, of ATP hydrolysis = 305 kJ/mole ave rea an understoo a l of the InstructIons on this Gas constant: R: 8.31 x 10.3 kJ/K/mole page. I have not used any prothIted materials nor have Std. Temp = 298 K I hel thle taking this exam. Faraday’s constant: 96.5 U V" mol" Igna l. (14) a. (1) Which of the following statements is true? 1., l {Liquid and solid water have the same number of hydrogenbonds per molecule of water. K Liquid water has more hydrogen bonds per molecule than does solid water. C. Solid water has more hydrogenbonds per molecule than does liquid water. D. Hydrogenbonding is a major factor in the structure of gaseous water. + I ' E. None is true b. (1) What is the pH of a dilute aqueous solution if [OH‘] is 3.45 x 10'5 M? D A. 3.45 B. 3.47 C. 5.53 D. 9.54 E. 10.55 F. 4.47 G. cannot be determined + I c. (1) Which protein amino acid has the R-group whose pKa is normally closest to physiological pH? LS$Z£EE€ e. (1) Which statement is true regarding the orientation of the R-groups in beta structures? E A. In the parallel beta sheet structures the amino acid R—groups are all on the same side 0 the sheet. B. In the antiparallel beta sheet structure the R—groups on alternate strands are on the same side of the sheet. g In parallel and antiparallel sheets consecutive R—groups on each peptide strand alternate sides of the sheet ,BfBécause of the free rotation around the alpha carbon, the R-groups can seek the least crowded region and are not restricted to a specific side of the sheet. (1. (1) Which protein amino acid has the R—group whose pKB is normally farthest from physiologic? pH? «DI'XLQ 5 a E. A and B 7 f ') f. (4) Diversity is important to life. What is the maximum number of different compounds that could be formed by the {is '3 i} 5 following [not limited to known biological molecules] 9‘ +_ \ 1) Formation of a peptide bond between L—alanine and L—leucine. l 2) Formation of a glycosidic bond between two D-glucopyranose molecules including all anomers. Z ? + 3) Membrane lipids consisting of glycerol, ethanolamine, phosphate plus palmitic acid &1'or steric acid, 1 4) A pentapeptide consisting of protein amino acids. £— AC 8 C I) E g. (1) Glycine is four times as soluble in solvent A as in solvent B. Phenylalanine is only two times as soluble in A as in B, while Lysine is ten time more soluble in A an in B. What qualitative judgment can be deduced about the relative nature of solvent A and solvent B? More .1 44km .l- I h. (1) Three of the four types of weak interactions that stabilize protein native conformation actually have the same basis of interacti n, blfiffier in sp cificity or deg ee. Which of th four weak interactions has a strikingly different basis? LYch A” Wt inan i. (1) AG“ for the hydrolysis of glycerol-S-phosphate to glycerol + Pi is -9.2 klfmole. Thus, you can conclude that 4, I A. this reaction will occur spontaneously in a living cell. I3 B. this reaction may or may not occur spontaneously, depending on the actual cencentrations of reactants and products. C. this reaction will only occur spontaneously if it is coupled to another reaction that has a more favorable G‘”. D. this reaction is so strongly favorable that it could be coupled to drive ATP synthesis. j. (1) In most biochemical reactions, AP and AV are A. negligible 4— i B. positive C. negative D. dependent on AG 5 k. (1) Which of the following processes does not describe the role of NAD+? l , A. It is an oxidizing agent. + /-—B. It is a hydride ion acceptor. C. It is a reducing agent. (Bf—‘lt is an electron acceptor. -E.’"lt is a water-soluble substrate. Name; page 2 rou s of the listed comounds at 25°C. The results are as follows: Ka of Carbox lGrou Ka’s of the ionizable 6:19.36, - M m3 at. a, 4.294» Jane/‘55 l,4, d. (3) Which of the above compounds is (are) biological c0mp0und(s) that we have encountered in this course? Give the common name(s) of any compound(s) that is (are) such biological compounds. “ e. (1) Calculate the isoelectric point for 4-aminobutanoic acid. (Show your calculations) xv.“ Mn 4 6) fr: 1. ' "L: p 6 f. (8) Plot a series of curves showing the fractional concentrations vs. pH for each of the Erotonation states of 4-aminobutanoic acid (from f’ully protonated to fully deprotonated). Be sure to clearly identi each curve. L-—_ _ P _-.__.-........ - I 1.......-.-—.--.--.—-— l..-.—.-. .0 P .- --......--p- --.-....--.... J-..--.——- -.-. -—- —_q..-...---_..-._--- .J.._-. -—...._-... e. m N 0' D Indicate which of the following characteristics most frequently apply to globular'and which to fibrous proteins by writin 3. (30) a. (10) X% 69 proteins. 8 :32 c , each of which is a «Bt‘Elastic —I'I'.‘Elongated (Le: 11 which every third residue is glycine, and the dentical polypeptides ine. Describe the specific role that might be sofi .I.. m .m 0e._ mm... f 9. n C .l. S 0 .ma 0 e Smgn S c V. O .1 MWSmfi. mm 1 ommum a m c 8.1— fiomtwpm mea .mRmmf anal... 801.100 .llmO.C..w 3.3de .flftcCy mwae todnx a mr. uxeeo O m Pi ur h n .n d caniV Tdewiy hBMHa .mhfish c 6 6.1.3... mngv mieno e k. a a.WS.Ur..m s m mumwm w noD P . fl .lnmee d .1 In 3 fl 9A.mAa.h H. mm 4w.sm V g Innap luv. ~ rhy m 32 mwsx . e r mesa mampad .l .I. [.m DIV. 1 .me mEYfleh m anew PnbuWe. (him.H imbdMln n h “.650” 0 3w... miwmpm .1 .1 l h MwnoAMdaP Arm Saccdme 68....Unoaadnm 0N tweamsoh [1 VS .ln 5 FE, .U.1~eiwm lTas Chfpmrd p n 6.moaa..m.1 Pommnhsm a BR fflWfl 36.1 mpmmw Od3fig ,ir .mRmommmmmmmm nm a geewfm a quhmg ow .mUaouddmfifle thcmcmhdam rOwnnflIThEi mLflmmd 6G ff.$)) ) 1 O n00 G e .. 0 m {wcnfl 3 I‘\ 1.! L.» .4 b mino - cids. ii .. by the properties of each of thes kco IL. WY? m3 m All-l m m... r \ D... e C M. $ P Ha. — . w an s N.H m4. i/w. .m s 2 de. OuC m m W. 07% n L. . Aw H “gr ) C C 0 2 . \ I I...“ s fH w; H.N H m mm... 2 2 I 1.”... m mch-zm Row .i u N I o - 1W, Inc. M m mH H \N..H .m H .m C O HzixlN m m C. LC E _ e m C N d c a. H b H L .m M N _ m w m %, 6 f t 6 CH0 .1 t . V m I C p QpCrf A’fi .m 0mm H N w 3 ._.u H yo h 6 . ‘ cl .w. m. g w L w W e n 1 me m w m e .h Ila Y e m. m m 0 m m _ Q U m 7 L. if Q "-1..- Ills-1... Air-5|"... . r._ n... .Ihumnnnzlvunifiv- .._r . L: -i I I w .1 n. u . .n. din-n...“ .1 LIfLInIFL .I . . . . . . J Jludldtul 1”! .TwLflmnwln u" .m- LnrlollrL .. L. - . . . . . J . n 1-1.1...I1l LI 4... . _ . _ . _ . . . ..I..-|._...r... 1 .1... .-..._r L... nu“. . . . . . GI...- I1J|uu lull... . . . . . r. . u . . . sfiJluafiJI-u. 1|... .3...”- .rL|..-r..|r- If... r-.. . _ . . . . . w. . . ... IIJIHIIIIII1JIJI 1:15: . . . . . . L _ . . _ . — . Janna-Junlfi .IleJld IJIDI unrqunrur air-if“ rLI+u ._.._.._... ... lurllllrllllrnillr L - . _ . _ . . .l. . . _ . J.._._.......I .. 111. . up sup-.. uLLr . . _ . . _ u.. .up... Equr - - I I .1 . ... ..+.1 Ir.- _ .rnr uliqulalfL-Ll Lou ..._....__ .._ IIJIn-IJIunfilnn—IHJIJITJnJ _.....r...._.... :fiJluufiquu.J-dnnJ-unl.||.nql.|..|u|_ I.le Ira—inn LI l L: I I I Inl.l II 23.11.;T.Iifi 6 8 OH’ equiv alents Calculate the isoelectric point for this peptide. a“ 3) (1) a Ca‘ I .,,_7 » rm f‘of’ Name: page 4 i or? 4. (25) a. Structural analysis of polysaccharides can be done by use of a procedure known as exhaustive methylation. In this procedure the intact polysaccharide is treated with methyl iodide. This results in conversion of all free hydroxyl groups (—OH) in the polysaccharide to methoxy groups (-OCH3). When all hydroxyl groups have been converted, the methyl iodide is removed from solution after which all glycosidic bonds are acid hydrolyzed. (The acid hydrolysis does not _ disrupt the ether linkages to the new methyl groups, but it will disrupt all glycosidic bonds including methyl-glycosides.) (Ifth a .94 a}; You carry out this procedure on 5 mM amylopectin. After exhaustive methylafion and acid hydrolysis are complete, you immediately neutralize the hydrolysate solution and go to lunch for 2 hours. When you return, you analyze the products - of your procedure. Structures of several compounds are shown below. Notice that they are lettered A through J. CHzoCHa H OH H H H CD) H (9 OCH3 H OH H H3C0 H H300 CH3 H OCH3 H OH r 3 '- 3 1) (5) Circle the structures shown above that you expect to find in your hydrolysate. (p 2) (2) Of the products you circled, write the letter of the product that will be found in highest concentration. 3) (3) If you carried out an identical procedure on 5 mM glycogen. Which of the products circled above would be found in significantly greater concentrations in this hydrolysate than in the hydrolysate of amylopectin. 6 I. t I b. 1) (I) Give the chemical name of the long~term energy storage family of compounds in animals. 2 ~ + L 2) (2) The advantages of this family of energy storage compounds over other energy storage compounds are (a) More energy can be released per unit time relative to other compounds. (b) It does not need hydration. so the weight of water required for hydration of other compounds is avoided. (c) More energy can be released per carbon oxidized to C02. (d) The carbons in this family of compounds are more highly oxidized than in glycogen. c. (12) Membrane lipids are amphipathic. For each of the following membrane lipids, name the components that make up the hydrophobic “tail” group and those that make up the hydrophilic “head” group. Lipid Compound Hydrophobic “Tail” Group Hydrophilic “Head” Group Phosphatidylcholine _ F4, W l Sphingomyeiin c cad} / #l’ 4/ Gangliosides W EA) W," J“ «mi . [cl-m ire-2&4“ Name: page 5 5. (17) a. (5)You have discovered a previously unknown isomerase, the substrate of which is not utilized in any other known biological reaction. You add various amounts of the substrate to a fixed volume of a crude extract of bovine muscle cells and assay for this enzymes activity by monitoring the rate of disappearance of substrate. Your reSults yield the plot A below. You then purify the enzyme from an identical volume of the same crude extract, and repeat the assay in the same total volume as before. The plot of the result from the assay of the purified enzyme is as follows. t I .3..l-.I I I | a I I.-I.-I. 1.‘.‘ .l. .l- ‘- I r'F-r I '8 I + K. [5] mM Since purifications usually lead to the loss of a significant fraction of the protein being purified, you would expect to see less activity from your purified enzyme, but instead you see more activity. Based on careful review of your procedures you confirm that it is not possible that you have a greater amount of enzyme in the second reactiOn mixture. Propose the most likely and lausible explanation for your results. Be as sp ific as possible in your inrpretation of your results. Ag pwré talkie-‘53" may; A keg <04 a. na-fLCaTvaeni‘nlwfi [ hr}— {SW 22? ar‘t-V’l— a—j’ 4—“, KM L‘LS M .2 (A, I" UN {3’ i A} (it..an ihrifui-n Lia A. fire. mi HF— fiar‘e’cfi—I‘b‘ “Lair-wit act-NM“; staph-W i {Gigi/k HQ LWW b. (12) Briefly describe the model for the kinetics of phosphofructokinase discussed in class and illustrate it by use of a diagram and a rough Vo vs. {S} plot in the presence and absence of an inhibitor. NOTE: The drawing and plot are not sufficient. F6 P You must also demonstrate an understanding of the entire concept by your explanatiOn. a14th QM 0P0 '3’ 'J- _ ' ‘ 61:: Fig“? PFL Le! {Irri‘lMi v +17: I , in 95g» 5.0, wt one peanut C‘flzoPdJ-‘u d ciyzrclrt‘j $12 6-4340 [5-] 23' amfl flwm 5M“Gr’rxr’r‘¢e 5' lac-m3 a ElmM aw fg_iif3 pFl—Q/ J-vk freeway. 1mm [4-67.5.3 €—-.27(-¢5P uLJZ/h ‘PF/(I/(Hg AME fl_ CiJfit gutsy,“ LaeL ate—am. Whm £32ng 3? Zav/ PFI‘Z r3- F’Q’é‘ 8P h’f LB 3-“ I0 It . ' / . f P / OS’ rp as: 442A; mad F92)(* Bp F6?! A93 Name: .— page 6 6. (13) The catalytic scheme of a well-known enzyme is shown below. Glu 211 H20 Kg/ Glu 2 11 a. (6) Give the following information about the enzyme and the reaction catalyzed. / ‘vuame of enzyme: Q4?— Class of this enzyme mlanced equation showing reaction catalyzed ’P’& --"7 P *kathwafls) in which the reaction participates b. (7) List the catalytic mechanisms illustrated in the - occurrence to the extent possible. Use only as many of the lines provi ed below as needed to complete your listing. QLIF¢ (“Ev " 23 fl (3* 7 c. 5' L¢2LLM L L‘ {394. Efiwf ([3 2 /< 75 FA Name; page 7 7. (32) a. (1) The reaction catalyzed by glyceraldehyde-3-phosphate dehydroge ase e ables the flycolysis pathway to ultimately accomplish what important goal of anaerobic metabolism? D b. (1) Specifically what does this reaction in into the resulting metabolic intermediate to make the above goal possible? ' in»; 7L3 ("é I c. 2) What ‘ the source f e ene gy to dae the incorporation of the above? Give a specific rather than general answer. MM: x??? —=7 ’29 . d. (1) Referring to part c. ove, this energy not only drives the incorporation of die necessary component, but also contributes to the lti t oal mentioned in part a. above by directly producing a product with very high '3 potential that will be used to drive synthesis of ATP in the next reaction. e. ( 1) What additional advantage does the g1yceraldehyde—3-phosphate dehydrogen se reaction rovide only organisms carrying out aerobic metabolism? ta» ouple th enrgy source mentioned in part c. bove to the f.(2 ) A” 2 ,Mcmw Hp -K reiult fent'oned in I . 1) If the reaction catalyzed by succinyl-COA synthetase is at equilibrium, what will be the effect of adding inorganic phosphate to the tea 'on ixture in the presence e engrme? {I e. . 1) Does glucokinase have a lower Km for glucose than exokinase? {him The formation of glucose-o-phosphate leads to the transport of more " I Q. into the cell. 3.: 2) The isomerization of glucose-6- hosphate to fructose-é-phosphate in glycolysis facilitates the two subsequent reactions catalyzed by he: - PAM: and tilde/Q96 k. (I) What enzyme catalyzes the rate limiting and major regulatory reaction of glycolysis? Mm 1. (5) The two reactions of glycolysis that generate ATP are the ansfer of phosphate from to ADP catalyzed b - and the transfer of phosphate from These types of reactions are known collectively as s‘wtvs’icc. /C¢v_C;( phosphorylation. m. (1) What other reaction of glycolysis aid you expect to proceed via the same reaction mechanism as that catalyzed by {FT- -- e 5") 2- EP n. (7) We have discussed several alternative fates of pyruvate during this course. List all compounds (that you know of) to (- which pyruvate’s carbon can be converted in one reaction 0-6 o. (3) There is no net synthesis of metabolic intermedia s b Tricarboxylic Acid (TCA) Cycle. Thus its primary function is than can be achieved anaerobically. However, we have also observed that TCA intermediates are sometimes u d as precursors t amino acids and other necessary biological X D compounds. What process makes this possible in plants? What makes it possible in animals? Wit C [w are p. (2) If a given metabolic pathway has only one regulated reaction, why will that reaction be rate limiting for the entire pathway? [:30 words] [M He with: ffeflol'iw «=19— Ju $9., we,ij L{mueryi!)[€_"¢¢7 bar/I 3c in w ‘" cats/vaulted Q’Lu; ‘ .. ice/WE: ar')‘ «9 We. MW/nme JJxa up 8. @ k Namei ———'page 3 (29) a. (2) Circle any ofthe following enzymes that exhibit(s) "induced fit" sub binding. exoki glucosephosphate isomerase aldolase citrate synth enolase b. ( ) Briefly explain the hjglggjgal importance of the particular mode of “induced fit" binding exhibited by the enzyme(s) you circled above. (<45 words) 015% La . Wt ekwie) b} “c5 g at 5- 7413* 52% W3 J» (aw-mm” W L21 . c. (9) What is the direct effect of increasing the concentration of each of the following metabolites on the net rate of energy metabolism (glycolysis &/or TCA cycle) under aerobic conditions? Indicate your answers by \/ marks. Increase Dfiease No effect/ 1) citrate 2) C02 ____|: ___ 3) fructose-2,6-bisphosphate / 4) ATP _ L __ 5) Aspartate / 6) NAD+ /__ Z 7) Succinyl-COA / 8) glucose / 9) AMP /. -_ cl. 1) (4) The AG‘" for the reaction catalyzed by malate dehydrogenase is +293l kJ/mole, and the AG‘" for the reaction catalyzed by citrate synthase is -31.4 kJ/moi. Illustrate how these two reactions can be coupled to produce a net reaction in the direction of citrate synthesis and calculate the AG” for the net reaction. Use names, not structures. Be sure to show all the reactants and products of each individual reaction, and cancel any that do not appear in the net reaction by drawing slash across its name. h me (ale. “‘7 a ’3 X. *K W... ( l . _ ‘ W”? ClifJfl . 7 ai A hf“ Name the roducts of he malate dehydrogenase reaction in the direction favored in the mitochondrial matrix. 0 (Leela. magma!" Name the Eicéucts of the malate dehydrogenase reaction in the direction favored in the cytoplasm of animals. ma. . . '" 2) (41 \ How do these thermodynamic results help to insure that re—oxidation of all NADH produced in aerobic energy metabolism by animals will drive ATP synthesis? (<45 words) 13‘ o arse b PM A (038* :J— gleir 6—15 Mar-36%“ cth We; SBA as; a; ._ C“ A Wine x‘FTfl waste gatw L aide; reload last A wall/l, Chet: W e. (8) Predict the short-term effects of each of the following disruptions of the normal functioning of the mitochondrial proton gradient on each of the indicated processes or concentrations of intermediates by placing a ” +” to indicate increased activity or concentration, ”- " to indicate decreased activity or concentration and "0” to indicate no effect: 1) rum /F f 11; Ml to 3g 3’ Insertion of an ionophore (artificial ion channel) in the mitochondrial inner membrane that would allow spontaneous flux of protons through the membrane from regions of higher hydrogen ion concentration to the region of lower concentration without entering the ATP synthase. TCA X Glycolysis Effect on: Oxidative phosphorylation :_ Binding of an inhibitory compound that blocks the proton channel of the mitochondrial ATP synthase so that protons cannot flow through it. Effect on: Oxidative phosphorylation _ Electron transport "9' 2) Electron transport: [NADH] 1; [Citrate]: #GPfiTcfiPE C t4 E K 5' 5‘ F amp—£13333 9. (32) a. (4) Write a balanced equation illustrating an anaplerotic means by which animal cells compensate for depletion of TCA intermediates due to their use in biosynthesis of certain biological carbon compounds. (No structures) b. (10) Calculate and itemize the energetic cost per net synthesis of TCA intermediate via i - . ' - - ' - . . direct cost of the above anaplerotic process plus any energy given up for the net synthesis of :1 TCA intermediate instead of oxidizing the carbons to C02. Specify each component of “energetic cost" and give your final answe...
View Full Document

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern