biochem exam prep 2

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biochem exam prep 2
2014-12-02 17:30:38
biochem exam prep

biochem exam prep 2
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  1. aerobic conditions due to exercise or due to tumor growth activate the transcription factor HIF-1 which
    activates aldolase
  2. Hexokinase is
    perform "induced fit" when binding to Glu
  3. The transfer of 3-phosphoglycerate to 2-phosphoglycerate was catalyzed by
  4. There is a reaction can be catalyzed by both enyzme A (Kcat=500) and enzyme B (Kcat=50). Which has the lower catalytic capacity?
    Enzyme B
  5. Competitive inhibition
    • -competes for active site, binds to enzyme
    • -Km increased, Vmax unaffected
    • -Increasing the concentration of substrate can over come the effects of the inhibitor
  6. Uncompetitive inhibition
    • Binds only to the ES complex to form ESB
    • Km reduced, Vmax reduced
  7. Noncompetitive inhibition
    • binds to a different site, can bind to S or E or ES?
    • Km unaffected, Vmax reduced
  8. The Michaelis-Menton equation does not apply to...
    allosteric enzymatic reactions
  9. The Michaelis constatn is
  10. What kind of enzymatic behavior follows a sigmoidal plot of reaction velocity versus substrate concentration?
  11. The active site of an enzyme is/contains (3 things)
    • -is frequently located in a cleft in the enzyme
    • -is the portion of the enzyme to which the substrate binds
    • -contains the reactive groups that catalyze the reaction
  12. Km of an enzyme is
    a measure of the affinity of the enzyme for the substrate
  13. Enzymes can speed up the rate of a reaction because
    enzymes lower the activation energy
  14. The "lock and key" model and the "induced fit model" can be used to explain
    the specificity of enzymes
  15. The rate of reaction
    relate to the degree of saturation of the catalyzing enzyme
  16. what is the V/Vmax ratio where S=Km
  17. An active enzyme with its associated cofactor/prosthetic group is termed a
  18. According to the steady-state assumption
    the concentration of enzyme-substrate complex remains constant with time
  19. Ordered sequential addition looks like
    a straight line with 4 lines into it? Maybe look those up
  20. How to find Km for Lineweaver-burk plot
    the X intercept is -1/km
  21. Homotrophic effects are caused by
    the substrate
  22. Heterotrophic effects are caused by
    nonsubstrate molecules?? Maybe ask someone
  23. R vs T state
    R state will be most active and therefore reach high point quickest
  24. Atp is a ------- of ATCase by----------
    ATP is an allosteric activator of ATCase by competing with CTP
  25. increases in F-2, 6 BP lead to the activation of PFK-1 is a type of
    Feedforward activation
  26. What does this reaction show?
    • -reductive synthesis of fatty acids
    • -electrons usually are provided by NADPH
  27. Aerobic vs anerobic bodyparts
    Liver is anerobic while heart is aerobic, exam 2 question 25
  28. Using water to split something into two parts is what type of reaction?
  29. Which group of three amino acid residues can be phosphorylated to modulate enzyme activity?
    tyrosine, threonine, and serine (the alcoholic ones)
  30. Which of the following is an example a compound that has higher phosphate transfer potential compared to ATP?
  31. The deficiency of which of the following of which of the following vitamins may cause subdermal hemorrhaging.
    Vitamin K, study what each of these does
  32. cells need energy for
    mechanical work and biosynthesis
  33. The following reaction is a type of
    substrate level phosphorylation
  34. GLUT3 Km
    has a low Km and performs basal glucose transportation
  35. Glut2 does what
    is expressed in the liver to remove excess glucose from blood and in the pancreas to regulate insulin?
  36. What contains more energy, fatty acids or simple sugars?
    fatty acids
  37. proteins that catalyze dephosphorylation reactions are called
  38. The Rossmann fold is..
    • -A NAD+ binding motif
    • -found in LDH and ADH
  39. The phosphorylation of glucose to G-6-P is a ------- reaction because------
    is a endergonic reaction that takes place because it is coupled to the exergonic hydrolysis of ATP
  40. the step that commits the cell to metabolize glucose is catalyzed by
  41. The conversion of 1,3-bisphosphoglycerate to 3-phosphoglycerate is
    one of the reactions of glycolysis in which ATP is produced
  42. The conversion of pyruvate to lactate does what?
    allows for recycling of NAD+
  43. The activity of the enzyme phosphofructokinase is stimulated by...
  44. NADH is produced at which step of glycolysis?
    G3PDH catalyzed reaction
  45. Inhibition of PFK would also likely cause what to happen in the cell?
    inhibition of hexokinase
  46. Which of the following molecules is a common fate of pyruvate in anaerobic metabolism?
  47. Which of the following is a carrier of acyl group
  48. whats more stable, a keto of enol form of pyruvate?
    The keto form
  49. This kinetic stability of activated carriers allows ------ to control the flow of free energy and reducing power in metabolism
  50. Sticking two things together is a type of
    ligation reaction, exam 2 question 49
  51. during glycolysis, how many pyruvate molecules are produced per glucose
  52. During yeast fermentation originated from one molecule of glucose, how many molecules of CO2 is produced?
  53. Breaking two things apart not using water is an example of a
    lyase reaction
  54. which of the following is/are correct about protein kinase A (PKA) and inhibitor (3 things)
    • 1) inhibitor interact with Pka through electro static interactions
    • 2) inhibitor interact with PKA through hydrophobic interaction
    • 3) No phosphate transfer from ATP to inhibitor
  55. Which of the following molecule is the least efficient as an energy source (contains the least energy)
    The CO2 because it has no hydrogen
  56. In general which of the following control of enzyme response the fastest
    allosteric control is faster than covalent modification which is faster than transcriptional control
  57. What molecules are active carriers to electrons?
    NAD+ and FAD+, look up structures (exam 2 question 56)
  58. The process to produce chymotrypsin is an example of
    proteolytic activation
  59. The conversion of pyruvate to lactate is
    the process result in sore muscles after exercise
  60. During glycolysis, how many NADH will be produced per glucose?
  61. Glucokinase
    • -Km is 50x greater than that of hexokinase
    • -it functions when glucose is abundant
  62. When PFK is inhibited, what happens?
    G-6-P increases to shut off hexokinase
  63. The breakdown of F-1,6-BP to GAP and DHAP was catalyzed by
  64. The last ATP production in glycolysis is catalyzed by
  65. look at the last page of exam 2