Exam3_08 - University of Houston BCHS 3304 Exam III Instructor Dr Briggs Apr 03 2008 Printed Name LAST FIRST Multiple choice 2 pts each(100 pts —

Info iconThis preview shows pages 1–11. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

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

View Full DocumentRight Arrow Icon
Background image of page 2
Background image of page 3

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

View Full DocumentRight Arrow Icon
Background image of page 4
Background image of page 5

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

View Full DocumentRight Arrow Icon
Background image of page 6
Background image of page 7

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

View Full DocumentRight Arrow Icon
Background image of page 8
Background image of page 9

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

View Full DocumentRight Arrow Icon
Background image of page 10
Background image of page 11
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: University of Houston BCHS 3304 Exam III Instructor Dr. Briggs Apr. 03, 2008 Printed Name LAST, FIRST Multiple choice, 2 pts each (100 pts) — Circle letter (Le. a, b., 0., d., or e.) of the most correct answer, then mark it on the Scantron sheet with a #2 pencil. Mark BOTH the exam AND the Scantron sheet. A table of half reactions and graph paper are at the end of this exam. 1). Catabolisrn is: a. The synthesis of complex molecules from simple ones b. The eating of human flesh c_. The acquisition of free energy from sunlight Degradation"p‘ficigiijp'léxniolecules:-..in-to e. Self-feeding organisms 2). The KM can be considered to be the same as the dissociation constant [(3 for E + S binding if: a. this statement cannot be completed because KM can never approximate KS b. ES —> E + P is fast compared to ES —> E + SJ‘i‘ c. the turnover number is very large m —_ O L ' _' ._ k2 e. Item/KM is near the diffusion-controlled limit NR 3). How many carbon atoms does a keto'o - se contain? a. One b. Two c. Three a: Five 4). What kind of functional group does an aldose contain? a. Ketone ‘3 b. Ketene Aldane wand 5). Find the initial velocity for an enzymatic reaction when VmX : 6.5 x 10—"5 molfscci [S] =3.0 x 10—3, M, and KM = 4.5 x10‘3 M. Let—"m‘fl‘ w’ ‘ ’ a. not enough information is given to make this calculation 'ii"’b'.‘:i':.;2;§6*x .: a, n a“ @ 1.4x10fizmol/sec \le 7 \lN‘Q-Siggfi Co iii, g $5" is a 0. 05 q d. 8.7 x 10"3 Incl/sec WWW—“é? ” WW.— w-WMMTWW ,..\ e. 3.9 x 10'5 mol/sec i524: "' C“ J L\ SE 2) Ar [43 i: 3 J . J r r: l ” \ F ’ f \a a; r 'r-"' J ’ — 7—;J 7). Which closeduring form of D-glucose is most energetically stable? 3. d—D—glucofuranose b. B—D-glucofuranose ee—D- lucopyranose s. :épyranose 1/ e. ct—D—galactose 8). In what conformation does lysozyme cause the D—ring sugar to adopt in its substrate in order to facilitate catalysis? a. Chair b. Bent chair 0. Three legged chair e. Boat 9). What is the identity of the catalytic triad in serine proteases? J . Asp—Tyr—Ser 7:3. sfiiHiéfid i a R v x; in if: . His—Trp-Ser b Jig ’i‘xls offl. d. Lys-His-Ser e. Arg—Trp—Ser l0)._____Whatistherrnost suitable substrate for lysozyrne? n 'f b. NAM—NAM ' NV“ c. MAN-MAN 7 d. NMA~NMG e. NUM—NUM 11). What are the catalytic residues of lysozyme? l Lys/Arg (f u 56- c. His/Lys .H; d. Ser/Glu 3:22.13 6 His/Ser 12). What is the Michaelis-Menton expression under uncompetitive inhibition? _ Vmfil t ‘KM+wm] Vmaxlsl LZKM + (I'[S] _' , I m. ERR-:1“ _ Vmaxlsl ‘ r .— m _ (Wm [S] "KM+$] _ vats] wKM+m <1 0 l .v‘F": H l L,“ V0 V0 13). What is the Lineweaver—Burke expression under competitive inhibition? 1 (1' m + {HEX 1 CL' ____u + __...._ S] Vinax uKM ML 1 max anax l 1 — + . [S] me S] 4. .. KM+m] 3 I “I a L ’~ . 14). What gets put into the oxyanion hole in the active site of serine proteases? U0 a. A water molecule used in the nucleophilic attack on the peptide substrate b. The C=O group in the sidechain of an Asn residue in the substrate'peptide c. The C=O group from the substrate peptide backbone r I_ The 0- generated during attack of the substrate peptide backbone C=O e. The OH group of the side chain of the active Site Set residue 15). The Michaelis constant, KM, is a. The rate at which the Michaelis complex goes on to form product The rate at which the Michaelis complex is formed he concentration at which the Va is half maximal d. The concentration at which the Va is maximal e. The concentration at which the initial velocity, V9, is rate limiting : 16). A measure of the catalytic efficiency of an enzymatic reaction is t' 3 , hm"? i Mi. =1.0, 1.5, 2.0, etc.) are characteristically 17). Some enzymes have attained catalytic perfection. Enzymes that fall into this category have " a. b. c. d. keg/KM which is less than 103 M'ls‘1 ' ks; ‘sfis'riiich is :. 3‘: KM is greater than VmaX/Z kcat of infinity lam/KM which is less than 10'8 M‘s" 3 s . 18). The lines on a LineweaVer—Burk plot for an uncompetitive inhibitor, with the variation of oc’ (Le. 19). What downstream product of ATCase acts as a feedback inhibitor? a. b. c. d. I Perpendicular Coincident on the Y—axis at UV,“ax Diverging Approaching Vmax in an asymptotic fashion ATP — (Ix/Witch’s MW UTP GTP rrr 20). An inhibitor would be most promising as a drug candidate if it had: 7: 1/ b. a K1: 4.7 x105 M KI: 1.5 x 108 M KI=4.7 x10’5M KM24.7x105M 21). What is the equation for or under competitive inhibition? a. b. C. e. (Kfilli) " (Kl+1/[I]) imam.) 1X ‘ la” Jr “fill - ' (MK/[1]) 22). What is the half—life of a first order reaction (ti/z) with a rate constant of 1.155 x 10'3 sec"? a. a i c. d. e. 1 min 100 min 1000 min 10000 min .rFI 23). Which is the most stable conformation of a pyranose sugar? ‘i 3-1,, 3 as: {fl C Stem . d; . Twist boat b. C. Boat air" e. I Ehi/elope 24). The rate—determining step in a sequence of reactions in a metabolic pathway -1s--‘a" Step witha-‘la‘rge ite’gatiyefreeengggy Has the lowest activation energy ' c. Is the fastest step /5\ d. Is the first step in the pathiNayE e. Is the last step in the patht-iaay;i 25). Through what major pathway or mechanism are ' D+ and FAD regenerated from NADH and FADHg, respectively? ' a. TCA cycle b. Glycolysis pathway Q! L c. Citric acid cycle I $25 if: e. Pymvate dehydrogenase 26). What is the name of the enzyme target for the nerVe poison Sarin? Lysozyme ' Carbonic anhydrase Hemoglobin Yeast Alcohol Dehydrogenase .Acetylcholinesterase'22-? ‘ vs» 27). What is the half-life of a second order reaction (tyz) with a rate constant of 1.155 x 10'2 M'Is‘1 and an initial substrate concentration of 1.2 x 10'1 M? a. 7.215 see. b. 72.15 see. i f 3:“; S . ' -"§ 0 “33.43 q 9' '3 ' d. 7,215.0 sec. Q ' e. 72150.0 sec. \ U .5 : if; ‘ f _ " W ‘ :. ,'. C, fir - .z Fifi? _ t. I c. d. Addition of oxygen e. Removal of oxygen 0 30). Consider the following metabolic reaction: Succinyl-CoA + Acetoacetate —> Acetoacetyl-COA + Succinate A °' = —l .25 kJ/mol The AG‘” for the hydrolysis of Succinyl-CoA is —33.9 kJ/rnol. . What is the AG‘)‘ for the hydrolysis of AcetoaCetyl-COA: AcetoacetyII5CoA —«+ Acetoacetate + CoA ‘3 W352 kJ/ l m” a ee A +32] kJ/mol +352 kJ/mol none of the above “5;; gt; 4» Cox-3 31). Consider the following metabolic reaction: 3-Phosphoglycerate ——+ 2—Phosphoglycerate AGO' = +4.40 kl/mol What is the AG for this reaction when the concentration of 2—phosphoglycerate is 0.290 mM and the concentration of 3-phosphoglycerate is 2.90 mM at 37°93, 33> (% D . 10.3 kJ/ 1 9‘“ ' k] be r. ' Li - file +15; Ln EOEng / MQ‘QO -. - wee (51%??le ' 4.30 kJ/mol —5.93 kJ/rnol —4.40 kJ/mo'l 32). What is the identity of the disaccharide below? a. Cellulose b. Lactose c. Sucrose d. Chitin . " c. Zy ophany d. Zyclops e. Zyo gen 34). In order for an enzymatic reaction obeying the Michaelistenten equation to reach 3/4 of its maximum velocity, v, 3/? er] @ [S] would need to be ZKM \) 0‘ “— fiifl J b. not enough information is given to make this calculation 6 c. [S] would need to be 50% Greater than KM _ lbw ' A? “D e. [S] would need to be 3/4 KM V” ' "1;; e: W a rim r can 5 #3 l g( +806 3 51'55 E Jr rm" 3' I , “03.0” E {I -- {Ac 1 V11 ’ it to Sitcom ii” It?“ ‘9 i 1% (L; "' ,...tsit_ns:t 435%th Limit 35). A competitive inhibitor (pyrrole-Z—carboxylate) of prolyl isomerase was added in a concentration of 1.882110“ M to a solution containing prolylisomerase and L—proline. The Vmax, and KM for the uninhibited enzyme at 25 “C are 20 M/s and l.53x_l_0'2 M, respectively, and the initial substrate concentration was 2.456x10‘2M. The K1 of this inhibitor is 7.23x104 M. What is the initial velocity (v0) of this inhibited enzyme? + Egg 5’"? a. 0.089 M/s M: ._ val b. l2.3 NUS a} 7:36 C. 6.17 M/S- (2 d- wail/Ila “ "° 36). For a Michaelis—Menton reaction, k1 : 2x102M'1s", k a = 3x1025'], and k2 = leOzs‘l. Calculate KM for this reaction. a. 300.0 M a t - 6 *3 2- b. 500.0M Ln 9 “Li—i?" = 3W6? 7 Li c. 0.4M ‘4 ‘- 2": 2” d. 200.0M -- -' 13M” \5 \ 3S \lflw QD‘UQ l' ~ \iw i -—/ f \L \ 37). Calculate AG for the following reaction at 44"C: ATP S AMP + PR with the following concentrations of [ATP]=10.0 InM, [AMP]=1.25 mM, [PPi]=2.S mM. (._ a. 30.5 kJ/mol g Q g a (a 1 b. —32.2kJ/m01 Ag : an o + garage-775.th Lin C. .- d‘rnfww‘._A,,,., "WI/fl A“ —50.48kJ/mol_§ . (321 + _F @391 “lg-twat) , a, ; nine} m i Lean-tine -. NVMMVW H, , Win r t if” 43:3 . tints) ~ snoctiauson 38). Compute the free energy for the overall reaction below using the half reactions that you were N} J asked to remember: phOSphoenolpyruvate + ADP 1: pymvate + ATP a. 31.4 kJ/mol ' . «I (“v r, l '\ , (A! . . m1??? ., ngio - *Ji 5i : Ll- \ '. /CT‘ 30.5 : ,. . a. y D 6 .th l . " " “’ d. "61.9 kJ/mol it l 3 its, 1r; 4 e. 61.9 kJ/mol (0' q r a 6""4 “f ‘ ’ a a o e loin“ . a [)- lo Ll Ll“l 213 \ . 39). Using the following data'determine the order of the reaction. (Note: Use graph paper at the end, if necessary) Time (s) 0 1 2 3 4 [A] (M) 3.1 1.55 1.05 0180 0.65 T a Zero order A W A - VA b. First order - , 1.2 eq- “SE‘ESiitli-ordér- ‘5 3 if? (3‘ 32% 7 0.81.21 U‘A ( (a d. Third order i (.35. 0.02855 0' ‘13 “(S B a go 5. VA. 3 e. Fourth order l l «037 63¢an 0 =98“ . g tr era's HUB, 164 5 087:; 6:14 1.5101 40flalculate KM from the following data. (Note: Use gra h paper at the end, if necessary) [£1] (mM) 0.1 E2 0.4 0.8 1 1.6 fl w; (mle) 0.34 0.53 0.74 0.91 1.04 2’5 0 1. ,. ». elopéwwm) J— -» 1—249 lrg'ik’C 08L | Uw....a. y c myg' '1: Or 90 i 4;» 0.06400 + are \{3 'L 41). What is the equilibrium constant (K) for the hydrolysis of glucosewl—P at 25°C. .9 .- _ a. 1.008 / {5&4 Va b. 0,209 K: e “bg N” \k g” c 2.62 l .. " [35$ . 6,6045ij r ___ 0330 .q f g ‘3qu gm 8 - 249) _ e. 9972.9 ‘ ‘9 , ‘ : Ht; 0 L ‘ \gl. 2 “{QM’IM \ “a. .7 irxriro - _ \ // - “.3175! - 73.21% x 1-— 42). Compute the catalytic constant, km, from an enzymatic reaction with a VIM and [Eh of 15 mM/s, and 2.42110"2 M, respectively. a. 6.25 sec'] _ b. 62.5 sec" \b/iow ._ a (a .1 g» 0. 0.0625 sec’1 2 .4 9; ’ " d 625 ’1 ‘2' l" ' ' _ __ KW \lwii rill E: . \L ;__fl_r was :.£i015 (N $341010 *' 43 ). Which of the following types of inhibition does the figure below reflect? 1/1JD Increasing [I] u: = 1 (no inhibitor) Slope = GKMi’Vmat ill-‘5] b. Uncompetitive c. Mixed d. Partial e. Uri—inhibited 44). Which of the following types of inhibition does the figure below reflect? Ui'fi increasing II? = u’ = t (noinhibitur) [ 1uu’ , are! , (IzmliKu (ll-UH“ ,I’i " “m”:— ::qumv;:k .ifi-fi‘IZ-y “Slaw aw Imam wme a Competitive b. Uncom etitive Partia Un—inhibited 45). Which of the numbered arrows in the figure below points toward a “high-energy” phosphoanhydride bond? 13 2 C 3 —:l d 4 g a 3....5 “€90? 6mm I “WW0 . / 4 ’1 1 ATHE /.n 0H1” (Th 3“ x h O—é—Ow foilL-cgc H2 i. 1/ a 2 ~ Ho ‘OH 46). Compute the free energy for the overall reaction below using the half reactions near the end of _ the exam: oreatine + ATP 3 phosphocreatine + ADP a. 4276 kJ/rnol r kJ/mol - r c. 413.1 kJ/mol 1" Ll 2/” ’l d. —30.5 kJ/mol o ~50. 3' e. 30.5 kJ/mol 47). What is the identity of the disaccharide below? a. Cellulose 6ongon O n Holng O H my 2 n2 5 OWHQH . ' 3 4 5 ' 01-1 H b. No . 0. Not enough information to determine 49). In whgtkparthgf. the cell does the metabolic oxidative phosphorylaticn occur? . imhondri-a; '- Nucleus b. c. Vacucle d. Cytosol e. Endoplasmic reticulum 50). With what catalytic residue does diisopropylphosphofluoridate (DIPF) react with in proteases? a. Lys b. His ...
View Full Document

This note was uploaded on 10/05/2010 for the course BCHS 3305 taught by Professor Briggs during the Spring '10 term at University of Houston-Victoria.

Page1 / 11

Exam3_08 - University of Houston BCHS 3304 Exam III Instructor Dr Briggs Apr 03 2008 Printed Name LAST FIRST Multiple choice 2 pts each(100 pts —

This preview shows document pages 1 - 11. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online