f04_exam_2_key - 1:! UHF I. (8 pts) Choose the correct...

Info iconThis preview shows pages 1–13. 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

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

View Full DocumentRight Arrow Icon
Background image of page 12
Background image of page 13
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 1:! UHF I. (8 pts) Choose the correct answar from the list on the right. Not all answars will be used. .AQ-hgh‘rchalns mapping —€—)-fibrouf D) globular I . . Mr G) glutamine Hj’cfil'l'ig’én B—glyeirge Bmyefin H A 1. Connective tissues and bones contain large amounts of the protein 2. The structure of kinesin is very similar to the structure of the protein A 3. The peptides that coil around the neck of muscle mysoin are called 4. The expansion of microfilaments is limited by proteins. _.—-‘ 4L. 5. The amino acid essential to the collagen triple helix is / 6. Energy is converted into mechanical work by I: proteins. C1 proteins. 6 7. The structural components of cells are 8. The hydroxylation of proline in collagen requires Version4 Page 1 UC'B 1C CU 1C3UUP ll (12 pts, 1.5 each) Choose the one alternative that best completes the statement or answers the question. 9. Which of the following can carry “cargo”? A) keratin B) myosin BandC E) A,B,andC 10. Tubulin is a good target for anticancer agents because a most chemotherapies target cells with arrested cell cycles Y ’ f A u ‘microtubule assembly is important in cell division Ea“ “Mai,- 'i " C) movement of cargo is inhibited along microtubules D) all of the above E) none of the abovo 11. (5-33) The papaya plant contains the enzyme papain which is a collegenase. Which of the following are true A) Papain in the primary constituent of meat tenderizer \/ B) Addition of fresh papaya to a Jello salad helps to make it gel fasteri C) Addition of cooked papaya to a Jello salad makes it gel slower D Addition of fresh papaya prevents the J c110 salad from gellingv and D 12. The protein actin can exist in two forms: A globular and polymericV' ) globular and deactivated C) GTP and ATP binding forms D) all of the above. E) none of the above. 13. The bundles of myosin tails in a muscle cell are called: A) cytoskeleton @ thick filaments thin filaments D) all of the above. E) none of the above. Version4 Page 2 . D UG'G 1r_' r_'U lr_':UIJP 14(Co'led coils are part of the structure of which of the following proteins? (geratin B L. mysoin 3L ,B,andC 15. ( 5-21) The bacteria, Clostridiurn perfringens, that is the causative agent of gas gangrene secretes an enzyme that cleaves the peptide bond ----X--—Gly---Pro———Y~— between the Gly and Pro residues. Why is this enzyme particularly damaging to animal tissues and does not affect the bacteria? A) Animal tissues do not contain an inhibitor of the protease and bacteria have anfii inhibitor. B W The enzyme only works when oxygen is absentx @‘Ufimal tissues are rich in collagen. \/’ ) The bacterial proteins are very poor in gly and pro residuesx E) none of the above 16. Microtubules and microfilaments are similar in what ways: A) they cannot disassemble once formed K B) they are both assembled from globular subunitsv‘ C they both bind XTPs V a: and C ) AandB D1. (8pts) (8 pts) Choose the correct answer from the list on the right. Not all answers will be I) hydrolase J) acid base catalysis l7. Oxidation—reduction reactions are catalyzed by the A class of enzymes. Version4 Page 3 USE 1|: CU 1CIUUP ’ 18. Reactions to move groups in a molecule are carried out by the C class of enzymes. 19. Many enzymes require the presence of a bound 6 that acts as the catalyst. 20. Enzymes bind b to make products. 21. In a diagrammatic depiction of free energy versus reaction progress, the point of highest energy is known as the state. ythe CI 67 22. Reactions of bond-forming coupled to ATP hydrolysis are catalyzed b class of enzymes. 23. Reactions to eliminate groups to form double bonds are carried out by the class of enzymes. 24. Reagents that mimic substrates but become covalently bound and “mar ” the active site are called E labels. IV. (12 pts, 1.5 each) Choose the one alternative that best completes the statement or answers the question. 25. The activity of some enzymes can be regulated by the following: A) protease inhibitors/ B) zymogen activation V” utoactivation / ll of the above E) none of the above Version4 Page 4 . t! UC'B 1C CU 1C3UUP 26. Which of the following amino acids is capable of participating in covalent catalysis? A) Set v B) Arg - C) Cys v D) Glu E) A, B A, C A, D H) none of the above I) all of the above 27. The types of catalytic mechanisms include: A) acid—base catalysis V B) covalent catalysis V C) metal ion catalysis and C A, B, and C 28. The active site of an enzyme A) is frequently located in a cleft in the enzyme B) is the portion of the enzyme to which the substrate binds C) contains the reactive groups that catalyze the reaction @excludes water during the reaction to increase electrostatic interactions ‘/ \/' all of the above 29. What are the two ways to increase the rate of a chemical reaction. @crease the temperature and add a catalyst. / Decrease the temperature and change the pressure. X C) Increase the temperature and decrease the substrate)! D) all of the above E) none of the above 30. Allosteric enzymes A) have only one active site 7: are regulated by covalent modification Vt @ave more than one polypeptide chain \/ ) catalyze several different reactions within a a metabolic pathway ‘4 E) all of the above Version4 Page 5 . U UC'B 1C CU 1C3UUP 31. Some functions of enzymes include: I A) the addition or removal of a substance to a substrate V B) the rearrangement of a substrate L" C the alteration of the reaction temperature l @A and B A, B, and C a 5““ 32. In the induced-fit model of substrate binding to enzymes ‘ (ii ' A) the substrate changes its conformation to fit the active site b i the active site changes its conformation to fit the substrate C) ) there is a conformational change in the enzyme when the substrate binds V D) there is aggregation of several enzyme molecules when the substrate binds E) none of the above V. (8 pts) Match the following. Not all answers will be used. A) maaeimal velocity B-)"l'ryperbolic Q—kmt D) straight Wetitive Elinitial velocity G) velocity H) competitive 1H3} MM 33. The progress of a reaction, measured as the disappearance of substrate or the appearance of product over a specific time period, is called the . 34. When } velocity. is equal to KM, the reaction velocity is equal to half the maximum 35. The symbol for the Michaelis constant is j . 36. The equation : = Vmax/[Eh describes the turnover number. 37. The velocity at the start of the reaction, or Va, is called the F 38. A compound that. affects theVmax but not the KM is a 6’ inhibitor. Version4 Page 6 .1U Ilf‘_'l'. l-v‘ I‘ll IfTIIIP 39. When enzyme is statur’ated with substrate, the reaction approaches . 40. The plot of substrate concentration versus V0 results in a 5 curve. VI. (12 pts) Choose the one alternative that best completes the statement or answers the question. 41. Mixed inhibitors have the following effects on KM and Vmax'. A) They alter the value of KM but not Vmax B They alter the value of Vmax but not KM @They alter the value of KM and met/ ) none of the above E) all of the above 8 value. 42. The affinity of enzyme binding to its substrate is approximated by the A) Vmax (BDKM "'C') [S] D) V0 E) none of the above e enzyme-catalyzed reaction, as substrate concentration increases the reaction 43. In a simpl velocity: u A) continues to increase linearly at higher substrate concentrations \7 g ., B5 increases loganthmrcally at higher substrate concentration \/ " increases at a lower rate at higher substrate concentrations [.1 D) none of the above E) all of the above 44. ADP regulation of phosphofructokinase activity is a type of: A suicide substrate inhibition allosteric regulation C) transition state inhibition D) none of the above E) all of the above Version4 Page 7 (gr:- “U0 1r— Lu J.r_.1.ulu Use the figure below to answer the following questions: Viv-“7 [kn-vs. D (0 Mb a“, \ “w E ‘3‘ q.) .L tn BA Vle 45. Which point(s) or line(s) correctly identifies a competitive inhibitor? A) A B) B C é) a E) E F) none of the above 46. Which line(s) or point(s) correctly identifies the Vmax? A) A B B C D) D E) E and D w, We 47. The x axis and y axis, respectively, represent in this figure: A) V0, [S] B) [S], Vo C NW, 1/ [S] @1118], 1N0 E) none of the above 48. Which point(s) or 1ine(s) correctly identifies the Km? A) A B) B C) C D D A,B ) B,C G) A,C Version4 Page 8 n J. UL.- u 1r. LU ar_. Lulu VH. (8 pts) Match the following. Not all answers will be used. “a “is W C) membrane -B')"“triacylglycerols (or triacylglycerides) W F) one W1 More holesterol tegral 49. A type of lipid found in bilayers that is a precursor to steroid hormones is /- J I 50. Proteins anchored within a bilayer are described as proteins. 51. Proteins attached to other membrane proteins or loosely associated with lipid head groups are called (:3. proteins. 52. A transport protein that moves two substances across a membrane in the same direction is classified as a g): . 53. is/are primarily for storage of fatty acids. 54. A transport protein that moves two substances across a membrane in opposite directions is classified as a 55. A transport protein that moves a single substance is classified as a 56, Saturated fatty acids contain double bonds. Version4 Page 9 UC'B 1C CU 1C311P VIII. (12 pts) Choose the one alternative that best completes the statement or answers the question. 1 57. Which of the following is (are) found in a glycerophospholipid? A) glycerol backbone w" B) esterified fatty acid group V" C phosphate derivative as the head group/ all of the above none of the above 58. Which phospholipid would you choose to make a membrane that would be fluid at very cold temperatures? 5 B (3' bass B B C C I/ none of the above 59. A membrane is impermeable to charged molecules and does not allow pass because of: A the thickness of the membrane a he hydrophobic nature of the membrane L/ C) the hydrophilic nature of the membrane D) all of the above E) none of the above age of ions 60. In the sodium—potassium pum sodium is transportf the cell and potassiu@he cell, both against concentration gradients = sodium is transporte to the cell and potassium out of the cell, both against concentration gradients n as C) sodium is transported out of the cell and potassium into the cell, both in the same directio concentIation gradients D) sodium and potassium are both transported out of the cell against concentration gradients Version 4 Page 10 .l‘l' 61. Which one of the following is a characteristic of phospholipds? A) Always contain choline and glycerol 5‘ Are an important source of energy Are a major component of membranes / D) Are not charged in the body )1 E) Are not soluble in water 2‘ 62. The carbohydrate portion of a glycoprotein is found: A) on the interior side of the cell membrane B spanning the cell membrane @on the exterior side of the cell membrane 1/ all of the above E) none of the above 63. The fat—soluble Vitamins include: Vitamin A, Vitamin D, Vitamin K ) Vitamin A, Vitamin D, VitaminQ’ C) Vitamin C, Vitamin H, Vitamin K D) all of the above E) none of the above 64. Which of these characteristics is n_ot_found in naturally occurring fatty acids in H .- I als? ey are foand unassociated with other molecules ) they are amphipathic / C) if unsaturated, they occur in the cis configuration / D) most, but not all fatty acids contain an even number of carbon atoms \/ Version 4 Page 11 UC'B 1.: CU lfiillP P 1 t: IX. (8 pts) Based on your CPR essay (DO NOT RECREATE 1T) 1mm: describe the chymotrypsin mechanism. Include the active site amino acids, the transition state stablization and how substrate specificity occurs. - ‘ “at iii-d, :2?“ £31.54 33‘?" glwgfiE/(Rfi hm. if V X. (6 pts) (based on 5-32) You are studying diseases of collagen in the repeat motif: (Gly—X—Y)n where X is usually proline and Y is hydroxproline) and found a number of mutants in the procollagen gene. Fill in the blanks with the ap ropriate letter: i _ ~— } , ,,, g A v A) (Glu—ILY)“ _ I QR“ Cam I (farm H. bandit; C «.fgdeL‘u I “iii. #94 B) (Gk/"P4911 -— 00% OK) but {Connoi‘ M— ii bat-'14.?» C)@P-Y)n , W 0.4 , ram. LL m; as 65. Which mutation would have the LEAST probable effect? H t .- . V2} IJL A) Ma firstde re is Md“ ‘f a B) (5b (swag: M of", i n! pg . {a deg. C P t “55' ’ til/{351059 wad“ l ! i .‘ _ fl C9 @iéflst '. tied 66. Which mutation would most likely have an intermediate to strong effect? A \ r , ,1 (1» .ifrmk. {saw CQLMh fiupgwd f {MOE Kb i‘g" IOU)“:- ._; _, we ' Men. om {we M is 5»! '3‘}? “#5345 “Pig "‘9" L" W . 4'.“ .. - i" Iii” pm [@531 "if . slid-j ' and? CREE-Sahara is Hag-l r? {_ l§ 'w f 5 __ I ' g . A (L U“) ‘ ‘3‘ CAM "*3 ' " r -- r .w t . ML. ‘3 {23; 2...! i; halide [LL 4 £51! i; :35 grade. M) Summit - r : Version4 Page 12 at", W UC'B 1.: CU 67 mutation would have the MOST probable effect? B I " (1133:!“ “Ea-113mm Was-rm and WC‘--Ji5i Fm“ C) (3 ., M _ (QD‘TYWKQE —" H1109!“ XI. (6 pts) Answer the following short answer questions. BE VERY BRIEF, YOU SHOULD ONLY NEED A FEW WORDS TO EXPLAIN 1! 68. (7-15) The enzyme hexokinase acts on 6 carbon sugars in carbohydrate metabolismhkd From the table below, which is the preferred substrate and explain the data? LDPVJC Vmax [Vi Substrate Km . r .r0~ fructose 7 x 10‘4 Vest-“m 1.8 59's; glucose 1 X 10“4 4/ 1.0 r _ . Wfirui‘é , bbd UM L, . I H_ H. r it. VELV _. ‘ ULLLogmwxfitB \EVJQ ‘r‘ ‘J' i; Lklk’qn' if ’j “U K: a A. r l" .. .‘ ., Ctr ~. 69. (8-31 and in class animation) In fluorescence photobleaching recovery studies, fluorescent probes are attached to membrane proteins in a cell. An intense laser beam is focused on a small area and destroys (photobleaching) the fluorescent probes in the area of the laser beam. What happens to the fluoresence in that area over time? Why? My”? t | A A. i T)“ LDC/M use-‘3, 0J3 "w M. Lark V‘vxswhtaai... i, mew L r\ I ‘UML “glued? U\'\.Q,\=r,l,st»:,r_ M..— Li. Wm . rum, ‘ r. at“ , b/LLCP" rota I |_ it an to smug V. WWW/“11K o l an: M“. ,i _ fr” L.)- rJ; 1“. Version 4 Page 13 1C31CP P. J. ...
View Full Document

This note was uploaded on 12/30/2010 for the course CH 369 taught by Professor Kbrowning during the Spring '07 term at University of Texas at Austin.

Page1 / 13

f04_exam_2_key - 1:! UHF I. (8 pts) Choose the correct...

This preview shows document pages 1 - 13. Sign up to view the full document.

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