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Biochemistry Examination 2

  1. What are the three types of reversible enzyme inhibitors?
    • 1) competitive
    • 2) noncompetitive
    • 3) uncompetitive

    [Note: The uncompetitive inhibitors make up for less than 1% of the enzyme population, so you will not need to worry about these as much.]
  2. Competitive inhibition may be reversed by _________ substrate.
    increased
  3. Competitive inhibitors are ____________________ to the substrate.
    structurally similar
  4. What occurs when a substrate has been competitively inhibited?
    After the substrate has been competitively inhibited, it means that the substrate can no longer bind the the active binding site of the enzyme [blocked by the competitive inhibitor.] So, because of this, the enzyme cannot catalyze the reaction of the substrate being catabolized into the desired product.
  5. If an enzyme is binded with a competitive inhibitor instead of the substrate, will the Vmax change?
    The Vmax will not change if the enzyme binds with a competitive inhibitor.
  6. Overall, the higher the concentration of the competitive inhibitor, the _______ the inhibition.
    greater
  7. In competitive inhibition, the Km _________, while the 1/Km _________.
    increases, decreases
  8. A ________________________ binds at a site other than the substrate-binding site.
    noncompetitive inhibitor
  9. Inhibition is ____________ by increasing the concentration of substrate.
    not reversed
  10. A noncompetitive inhibitor causes the Vmax to ________.
    decrease
  11. A noncompetitive inhibitor cause the Km to __________.
    not change
  12. Which inhibition process forms the IES complex?
    The noncompetitive inhibition process forms the IES complex.
  13. Explain noncompetitive inhibition.
    In noncompetitive inhibition, the inhibitor binds with the enzyme at a different binding site from the substrate-binding site. Therefore, the IES [inhibitor-enzyme-substrate] complex forms. This still hinders the reaction from being done, although the Km does not change [the Vmax does increase, though].
  14. The higher the concentration of the noncompetitive inhibitor, the _______ the inhibition.
    greater
  15. A competitive inhibitor binds _______________________.
    only to the free enzyme
  16. A noncompetitive inhibitor binds ________________________________________________________.
    to both the free enzyme and the enzyme-substrate complex
  17. An uncompetitive inhibitor binds _____________________________________.
    only to the enzyme-substrate complex
  18. In the presence of a competitive inhibitor, the Km and Vmax of an enzyme catalyzed reaction ________________________________________.
    increase and stay the same, respectively
  19. In the presence of a noncompetitive inhibitor, the Km and Vmax of an enzyme catalyzed reaction ________________________________________.
    stay the same and decrease, respectively
  20. In the presence of an uncompetitive inhibitor, the Km and Vmax of an enzyme catalyzed reaction _____________.
    both decrease
  21. The reaction where glucose is produced from lactate is _______________.
    gluconeogenesis
  22. The reaction where glycogen is produced from glucose is ____________.
    glycogenesis
  23. The reaction where glucose is produced from glycogen is _____________.
    glycogenolysis
  24. The reaction where lactate is produced from glucose is __________.
    glycolysis
  25. Gluconeogenesis is the reversed reaction of _________.
    glycolysis
  26. Glycogenesis is the reversed reaction of ______________.
    glycogenolysis
  27. What is the NET total of ATP after fermentation?
    0 ATP is the NET total of ATP after fermentation.
  28. What is the total amount of ATP used in glycolysis?
    0 ATP is used in glycolysis.
  29. What is the NET total of ATP after glycolysis?
    +2 ATP is the NET total of ATP after glycolysis.
  30. How many high energy bonds does ATP contain?
    ATP contains two high energy bonds.
  31. How many high energy bonds does ADP contain?
    ADP contains one high energy bond.
  32. Where does glycolysis occur?
    Glycolysis occurs in the cytoplasm.
  33. Does glycolysis require O2?
    Glycolysis does not require O2.
  34. Where does pyruvate dehydrogenase (PDH) breakdown two pyruvates to form 2 actyl CoA?
    Pyruvate dehydrogenase (PDH) breaks down two pyruvates to from 2 acetyl CoA in the mitochondria.
  35. Is O2 required when pyruvate dehydrogenase (PDH) breaks down two pyruvates to form two acetyl CoA?
    O2 is required when pyruvate dehydrogenase (PDH) breaks down two pyruvates to form two acetyl CoA.
  36. Where does the tricarboxylic acid (TCA) cycle occur?
    The tricarboxylic acid (TCA) cycle occurs in the mitochondria.
  37. Does the tricarboxylic acid (TCA) cycle require O2?
    The tricarboxylic acid (TCA) cycle does require O2.
  38. ___________ create fat from the acetyl CoA in the mitochondria.
    Hepatocytes
  39. Image Upload 2
    The reaction where glucose reacts to produce glucose 6-phosphate is catalyzed by ____________.
    transferase
  40. Image Upload 4
    The reaction where glucose 6-phosphate reacts to produce fructose 6-phosphate can be considered to be __________.
    reversible
  41. Image Upload 6
    The reaction where glucose 6-phosphate reacts to produce fructose 6-phosphate is considered a(n) _____________.
    isomerization
  42. Brain hexokinase has a Km for glucose of ___ mM.
    0.1
  43. Liver glucokinase has a Km for glucose of __ mM.
    10
  44. Which enzyme activity, the one in the brain or the one in the liver, will be most sensitive to daily fluctuations in the blood glucose level?
    The liver will be most sensitive to daily fluctuations in the blood glucose level.
  45. Define isozymes.
    Describes two polypeptide chains that catalyze the same reaction, having the same Vmax.
  46. How many ATP is spent after the first step of glycolysis?
    1 ATP
  47. How many ATP is spent after all three steps of glycolysis?
    2 ATP
  48. Image Upload 8
    How many molecules of ATP is generated after glycolysis?
    4 ATP is generated after glycolysis.
  49. Image Upload 10
    What is the NET total of ATP after glycolysis?
    The NET total of ATP after glycolysis is 2 ATP.
  50. ______ is _________ when two glyceraldehyde 3-phosphates are catalyzed to produce two 1,3 biphosphoglycerates.
    2 NADH, generated
  51. _____ is _________ when two 3-biphosphoglycerates are catalyzed to produce two 3-phosphoglycerates.
    2 ATP, generated
  52. _____ is _________ when two 3-phosphoglycerates are catalyzed to produce two 2-phosphoglycerates.
    0 ATP/0 NADH/0 H2O, generated/consumed
  53. _____ is _________ when two 2-phosphoglycerates are catalyzed to produce two phosphoenolpyruvates.
    2 H2O, generated
  54. _____ is _________ when two phosphoenolpyruvates are catalyzed to produce two pyruvates.
    2 ATP, generated
  55. ______ is ________ when two pyruvates are catalyzed to produce two lactates.
    2 NADH, consumed
  56. What is the total [NET] of NADH, ATP, and H2O generated/consumed after the priming stage?
    2 ATP is consumed [-2 ATP], 0 NADH consumed/generated [0 NADH], and 0 H2O consumed/generated [0 H2O].
  57. What is the total [NET] of NADH, ATP, and H2O generated/consumed after the splitting stage?
    0 ATP is consumed/generated [0 ATP], 0 NADH consumed/generated [0 NADH], and 0 H2O consumed/generated [0 H2O].
  58. What is the total [NET] of NADH, ATP, and H2O generated/consumed after the oxidoreduction-phosphorylation stage?
    2 NADH is generated while 2 NADH is consumed [0 NADH], 4 ATP is generated [4 ATP], and 2 H2O is generated [2 H2O].
  59. _____ is _________ when glucose is catalyzed to produce glucose 6-phosphate.
    1 ATP, consumed
  60. _____ is _________ when glucose 6-phosphate is catalyzed to produce fructose 6-phosphate.
    0 ATP/0 NADH/0 H2O, generated/consumed
  61. _____ is _________ when fructose 6-phosphate is catalyzed to produce fructose 1,6-biphosphate.
    1 ATP, consumed
  62. _____ is _________ when fructose 1,6-biphosphate is catalyzed to produce glyceraldehyde 3-phosphate.
    0 ATP/0 NADH/0 H2O, consumed/generated
  63. PDH reaction is as follows:
    pyruvate + NAD+ + CoASH ------> acetyl CoA + CO2 + NADH + H+
  64. The ΔG for the PDH reaction is:
    -8 kcal mol-1
  65. List the four enzymes from glucose to acetyl-CoA that are highly exergonic and subject to regulation:
    • 1)Hexokinase
    • 2) Phosphofructokinase-1
    • 3) Pyruvate kinase
    • 4) Pyruvate dehydrogenase
  66. What are the seven reversible steps in glycolysis?
    • 1) glucose 6-phosphate ---> fructose 6-phosphate
    • 2) fructose 1,6-biphosphate ---> glyceraldehyde 3-phosphate
    • 3) glyceraldehye 3-phosphate ---> 1,3 biphosphoglycerate
    • 4) 1,3 biphosphoglycerate ---> 3-phosphoglycerate
    • 5) 3-phophoglycerate ---> 2-phosphoglycerate
    • 6) 2-phosphoglycerate ---> phosphoenolpyruvate
    • 7) pyruvate ---> lactate
  67. What are the three irreversible steps in glycolysis?
    • 1) glucose ---> glucose 6-phosphate
    • 2) fructose 6-phosphate ---> fructose 1,6-biphosphate
    • 3) phosphoenolpyruvate ---> pyruvate
  68. What are the two oxidation-reduction steps of glycolysis?
    • 1) glyceraldehyde 3-phosphate ---> 1,3-biphosphoglycerate
    • 2) pyruvate ---> lactate
  69. What are the two substrate-level phosphorylation steps?
    • 1) glucose ---> glucose 6-phosphate
    • 2) fructose 6-phosphate ---> fructose 1,6-biphosphate
  70. Where does the pyruvate dehydrogenase reaction occur?
    The pyruvate dehydrogenase reacton occurs in the mitochondrial matrix.
  71. What are the five vitamins/coenzymes needed in order for the pyruvate dehydrogenase reaction to occur?
    • 1) Niacin
    • 2) Riboflavin
    • 3) Thiamine
    • 4) Lipoic acid
    • 5) Pantothetic acid
  72. Where does the chemistry occur in the activation of thiamine to thiamine pyrophasphate?
    Image Upload 12
  73. Image Upload 14
    Where does the chemistry occur in the activation of lipoic acid to enzyme-bound lipoamide?
    Image Upload 16
  74. Image Upload 18
    Where does the chemistry occur in the activation of pantothetic acid (vitamin B5) to Coenzyme A?
    Image Upload 20
  75. Image Upload 22
    Where does the chemistry occur in the activation of riboflavin (B2) to flavin adenine dinucleotide (FAD)?
    Image Upload 24
  76. Image Upload 26
    Where does the chemistry occur in the activation of Niacin (B3) to Nicotinamide Adenine Dinucleotide (NAD+)?
    Image Upload 28
  77. What occurs in reaction #1?
    The decarboxylation of pyruvate occurs in reaction #1.
  78. What occurs in reaction #2?
    The transfer of electrons and acyl group from TPP to enzyme-bound lipoamide occurs in reaction #2.
  79. What occurs in reaction #3?
    The transfer of acetyl from lipoamide to Coenzyme A occurs in reaction #3.
  80. What occurs in reaction #4?
    The transfer of electrons from lipoamide to enzyme-bound FAD occurs in reaction #4.
  81. What occurs in reaction #5?
    The transfer of electrons from enzyme-bound FADH2 to NAD+ occurs in reaction #5.
  82. Pyruvate dehydrogenase consists of _____ enzymes in its complex.
    three
  83. What is the precursor of thiamine pyrophosphate?
    Thiamine is the precursor of thiamine pyrophosphate.
  84. What is the precursor of enzyme-bound lipoamide?
    Lipoic acid is the precursor of enzyme-bound lipoamide.
  85. What is it precursor of Coenzyme A?
    Pantothenic Acid (B5) is the precursor of Coenzyme A.
  86. What is the precursor of flavin adenine dinucleotide (FAD)?
    Riboflavin (B2) is the precursor of flavin adenine dinucleotide (FAD).
  87. What is the precursor of nicotinamide adenine dinucleotide (NAD)?
    Niacin (B3) is the precursor of nicotinamide adenin dinucleotide (NAD).
  88. What is the function of niacin (B3)?
    Niacin (B3) helps synthesize nicotinamide adenine dinucleotide (NAD) which acts as a mobile electron carrier.
  89. What is the function of riboflavin (B2)?
    Riboflavin (B2) helps synthesize flavin adenine dinucleotide (FAD) which helps in enzyme-bound electron transfer.
  90. What is the function of thiamine (B1)?
    The function of thiamine (B1) is to form thiamine pyrophosphate (TPP) which aids in the decarboxylation of pyruvate.
  91. What is the function of lipoic acid?
    Lipoic acid is covalently conjugated to protein by an amide bond, and is then involved in enzyme-bound acyl and electron transfer.
  92. What is the function of pantothenic acid (B5)?
    The function of pantothenic acid (B5) is to be formed into coenzyme A, which acts as a mobile acyl carrier.
  93. List the order of the five reaction catalyzed by PDH in each catalytic cycle.
    • 1) activation of thiamine to thiamine pyrophosphate
    • 2) activation of lipoic acid to enzyme-bound lipoamide
    • 3) activation of pantothenic acid (B5) to Coenzyme A
    • 4) activation of riboflavin (B2) to flavin adenine dinucleotide (FAD)
    • 5) activation of niacin (B3) to nicotinamide adenine dinucleotide (NAD+)
  94. The conversion of glucose to two glyceraldehydes-3-phosphates ______________.
    consumes 2 ATP
  95. The conversion of two glyceraldehydes-3-phosphates to two 1,3-bisphosphoglycerates ________________.
    generates 2 NADH
  96. The conversion of two 1,3-bisphosphoglycerates to two pyruvic acids _______________.
    generates 4 ATP
  97. The conversion of two pyruvic acids to two lactic acids _______________.
    consumes 2 NADH
  98. Aerobic glycolysis, the conversion of glucose to two pyruvic acids, may be represented as the sequential sum of the following three subsets: the conversion of glucose to two G-3-P; followed by the conversion of two G-3-P to two 1,3-BPG; followed by the conversion of two 1,3-BPG to two pyruvic acids. So, what is the overall NET yield (generated minus consumed) of ATP for aerobic glycolysis?
    2 ATP
  99. Similarly, what is the overall NET yield (generated minus consumed) of NADH for aerobic glycolysis?
    2 NADH
  100. Anaerobic glycolysis, the conversion of glucose to two lactic acids, may be represented as the sequential sum of aerobic glycolysis, followed by the conversion of two pyruvic acids to two lactic acids. So, what is the overall NET yield (generated minus consumed) of ATP for anaerobic glycolysis?
    2 ATP
  101. What is the overall NET yield (generated minus consumed_ of NADH for anaerobic glycolysis?
    0 NADH
  102. The coenzyme that participates in the decarboxylation reaction is ___.
    TPP
  103. The coenzyme that functions as a mobile electron carrier is ___.
    NAD
  104. The coenzyme that functions as a mobile acyl carrier is ___.
    CoA
  105. The coenzyme that participates in enzyme-bound electron transfer reactions is ___.
    FAD
  106. The coenzyme that functions in enzyme-bound electron transfer and acyl transfer reactions is ___________.
    lipoic acid
  107. Which coenzyme is not derived from a water-soluble vitamin?
    lipoic acid
  108. Vitamin B1 is the water-soluble vitamin precursor for ___.
    TPP
  109. Vitamin B2 is the water-soluble vitamin precursor for ___.
    FAD
  110. Vitamin B3 is the water-soluble vitamin precursor for ___.
    NAD
  111. Vitamin B5 is the water-soluble vitamin precursor for ___.
    CoA
  112. The Cori cycle circulates through what two organs/cells?
    the liver and the red blood cell
  113. How many ATP is consumed in the Cori cycle in the liver?
    6 ATP
  114. How many ATP is generated in the Cori cycle in the red blood cell [erythrocyte]?
    2 ATP
  115. What are the two characteristics of gluconeogenesis?
    • 1) uses glycolytic enzymes that catalyze readily reversible reaction in glycolysis
    • 2) requires new enzymes to circumvent those steps in glycolysis that are highly exergonic
  116. What are the three enzymes in glycolysis that catalyze highly exergonic reactions?
    • 1) hexokinase
    • 2) phosphofructokinase-1
    • 3) pyrucate kinase
  117. How many reactions in glycolysis are highly exergonic, and what are they?
    Three reactions in glycolysis are highly exergonic, and include:

    • 1) glucose ---> glucose 6-phosphate
    • 2) fructose 6-phosphate ---> fructose 1,6-biphosphate
    • 3) phosphoenolpyruvate ---> pyruvate
  118. The pyruvate kinase enzyme is replaced by ___________.
    two enzymes
  119. The phosphofructokinase-1 enzyme is replaced by __________________________.
    fructose-1,6-biphosphotase
  120. The hexokinase enzyme is replaced by _____________________.
    glucose-6-phopatase
  121. _________ and _____________ must be coordinately regulated.
    Glycolysis, gluconeogenesis
  122. Anaerobic glycolysis yields _ ATP.
    4
  123. Gluconeogenesis requires _ ATP.
    4
  124. In the Cori cycle, what occurs in the liver?
    gluconeogenesis
  125. In the Cori cycle, what occurs in the red blood cell?
    glycolysis
  126. In what two organs/cells does the Alanine cycle occur?
    The Alanine cycle occurs in the liver and muscle cell.
  127. In the Alanine cycle, what occurs in the liver?
    gluconeogenesis
  128. In the Alanine cycle, what occurs in the muscle cell?
    glycolysis
  129. In the Alanine cycle, how many ATP molecules are consumed in the liver?
    10 ATP molecules are consumed in the liver.
  130. In the Alanine cycle, how many ATP molecules are being generated in the muscle cell?
    5-7 ATP molecules are bing produced in the musscle cell.
  131. The reaction in glycolysis that is catalyzed by hexokinase is bypassed by the reaction(s) catalyzed by _____________________.
    glucose-6-phosphatase
  132. The reaction in glycolysis that is catalyzed by phosphofructokinase I is bypassed by the reaction(s) catalyzed by ___________________________.
    fructose-1,6-bisphosphatase
  133. The reaction in glycolysis that is catalyzed by pyruvate kinase is bypassed by the reaction(s) catalyzed by __________________________________________.
    pyruvate carboxylase and PEP carboxykinase
  134. The reaction catalyzed by the same enzyme in glycolysis and gluconeogenesis is the reaction catalyzed by _______________________.
    phosphoglycerate kinase
  135. What are the two properties of enzymes subject to regulation?
    • 1) They catalyze reactions that are highly exergonic.
    • 2) They catalyze the first highly exergonic reaction that commits a pool of metabolites to the pathway in question.
  136. List the five general ways of regulating enzymes.
    • 1) Induction
    • 2) Repression
    • 3) Create isozymes
    • 4) Reversibly modify existing enzymes
    • 5) Irreversibly modify existing enzymes
  137. Define induction.
    Induction is the process of making more of a specific enzyme.
  138. Define repression.
    Repression is the process of making less of a specific enzyme.
  139. Define isozyme.
    An isozyme is an enzyme that is similar to another specific enzyme, but with differnt properties.
  140. List all four enzymes from glucose to acetyl-CoA that are highly exergonic and subject to regulation.
    • 1) hexokinase
    • 2) phosphofructokinase-1
    • 3) pyruvate kinase
    • 4) pyruvate dehydrogenase
  141. Which enzyme is the least regulated of the four enzymes involved with the highly exergonic/regulated rectoins of glycolysis/gluconeogenesis?
    Hexokinase is the least regulated of the four enzymes involved with the highly exergonic/regulated reaction of glycolysis/gluconeogenesis. This is because as more of the glucose 6-phosphate is produced, it acts as an inhibitor of the glucose molecule binding to the hexokinase.
  142. As the concentration of ATP increases in a reaction catalyzed by phosphofructokinase-1, and the concentration of AMP decreases, then the rate of glycolysis should ________.
    decrease
  143. Which enzyme of the four enzymes of glycolysis/gluconeogenesis that are highly exergonic/regulated is the most regulated?
    Phosphofructokinase-1 is the most regulated enzyme of the four enzymes of glycolysis/gluconeogenesis that are highly exergonic/regulated.
  144. What is allosteric inhibition?
    The regulation of an enzyme or other protein by binding an effector molecule at the protein’s allosteric/active site.
  145. In a reaction catalyzed by phosphofructokinase-1, when the concentration of ATP is low, and the concentration of AMP is high, then the rate of glycolysis should ________.
    increase
  146. In the reaction that is catalyzed by phosphofructokinase-1, when the concentration of citrate is high as well as the concentration of acetyl-CoA, then the rate of glycolysis should ________.
    decrease
  147. In the reaction that is catalyzed by phosphofructokinase-1, when the concentration of lactic acid and protons increases, then the rate of glycolysis should _________.
    decrease
  148. What are the three inhibitors of phosphofructokinase-1?
    • 1) ATP
    • 2) citrate
    • 3) H+ [protons]
  149. What are the two activators of phosphofructokinase-1?
    • 1) AMP
    • 2) Fructose-2,6-biphosphate
  150. In the reaction that is catalyzed by pyruvate kinase, when the concentration of ATP increases, the rate of glycolysis _________.
    decreases
  151. In a reaction catalyzed by pyruvate kinase, as the concentration of alanine increases, then the rate of gluconeogenis _________.
    increases
  152. In a reaction catalyzed by pyruvate kinase, as the concentration of alanine increases, then the rate of glycolysis _________.
    decreases
  153. In the reaction catalyzed by pyruvate kinase, when the concentration of fructose-1,6-biphosphate increases, the rate of glycolysis _________.
  154. In the reaction catalyzed by pyruvate kinase, when the concentration of alanine increases, then the rate of gluconeogenesis _________.
    increases.
  155. What is the sole inhibitor of hexokinase?
    Glucose 6-phosphate
  156. What is the sole activator of pyruvate kinase?
    Fructose 1,6-biphosphate
  157. What are the two inhibitors of pyruvate kinase?
    • 1) ATP
    • 2) alanine
  158. Where does the reaction catalyzed by pyruvate dehydrogenase occurs?
    The reaction catalyzed by pyruvate dehydrogenase occurs in the mitochondria.
  159. Does the reaction catalyzed by pyruvate dehydrogenase require O2?
    The reaction catalyzed by pyruvate dehydrogenase requires O2.
  160. In a reaction catalyzed by pyruvate dehydrogenase, when the concentration of ATP increases, then the rate of the reaction _________.
    decreases
  161. In a reaction catalyzed by pyruvate dehydrogenase, when the concentration of NADH increases, then the rate of the reaction __________.
    decreases
  162. In a reaction catalyzed by pyruvate dehydrogenase, when the concentration of acetyl-CoA increases, then the reate of the reaction __________.
    decreases
  163. In a reaction catalyzed by pyruvate dehydrogenase, when the concentration of ADP increases, the rate of reaction _________.
    increases
  164. In a reaction catalyzed by pyruvate dehydrogenase, when the concentration of NAD+ increases, the rate of reaction _________.
    increases
  165. In a reaction catalyzed by pyruvate dehydrogenase, when the concentration of CoASH increases, the rate of reaction _________.
    increases
  166. What are the two inhibitors of pyruvate dehydrogenase?
    • 1) acetyl CoA
    • 2) NADH
  167. What are the three activators of pyruvate dehydrogenase?
    • 1) ADP
    • 2) NAD+
    • 3) CoASH
  168. When the pyruvate dehydrogenase is phosphorylized, this renders the enzyme ________.
    inactive
  169. In gluconeogenesis, when the concentration of the acetyl-CoA is increased, then the rate of the pyruvate carboxylase is _______.
    activated
  170. Gluconeogenesis starts in the ____________ and ends in the __________.
    mitochondria, cytoplasm
  171. In gluconeogenesis, when the concentration of AMP is high, then the production of fructose-1,6-biphosphate is _________.
    inhibited
  172. Fructose-2,6-biphosphate is a(n) _________ of phosphofructokinase-1.
    activator
  173. Fructose-2,6-biphosphate is a(n) _________ of fructose-1,6-biphophatase.
    inhibitor
  174. Define free energy (ΔG).
    Free energy, ΔG, is a quantitative measure of whether a chemical reaction occurs spontaneously.
  175. Anabolism ________ ATP.
    requires
  176. Catabolism ________ ATP.
    produces
  177. Define free energy (ΔG).
    Free energy, ΔG, is a quantitative measure of whether a chemical reaction occurs spontaneously.
  178. When ΔG is negative (ΔG<0) the reaction is considered _________ and ____________.
    exergonic, spontaneous
  179. When ΔG is 0 (ΔG=0) the reaction is considered ____________________ and ______________.
    to be at equilibrium, no net change
  180. When ΔG is positive (ΔG>0) the reaction is considered ___________ and _______________.
    endergonic, not spontaneous
  181. Gibb’s free energy equation:
    ΔG=ΔG0 + RT ln(products/reactants)
  182. The reaction in glycolysis that is catalyzed by hexokinase is bypassed by the reaction(s) catalyzed by ____________________.
    glucose-6-phosphatase
  183. The reaction in glycolysis that is catalyzed by phosphofructokinase I is bypassed by the reaction(s) catalyzed by _____________________________.
    fructose-1,6-bisphosphatase
  184. The reaction in glycolysis that is catalyzed by pyruvate kinase is bypassed by the reaction(s) catalyzed by ______________________________________________.
    pyruvate carboxylase and PEP carboxykinase
  185. The reaction catalyzed by the same enzyme in glycolysis and gluconeogenesis is the reaction catalyzed by ______________________________.
    phosphoglycerate kinase
  186. The reaction catalyzed by glucose-6-phosphatase _____________________________.
    requires neither ATP nor GTP
  187. The reaction catalyzed by fructose-1,6-bisphosphatase ____________________________.
    requires neither ATP nor GTP
  188. The reaction catalyzed by pyruvate carboxylase _______________.
    requires an ATP
  189. The reaction catalyzed by PEP carboxykinase _______________.
    requires a GTP
  190. The reaction catalyzed by phosphoglycerokinase _______________.
    requires an ATP
  191. The reaction(s) required to completely bypass the pyruvate kinase reaction ________________________________.
    require(s) both an ATP and a GTP
  192. So, how much energy is required to make ONE molecule of glucose from TWO molecules of pyruvic acid?
    four ATP and two GTP
  193. The activity of fructose-1,6-bisphosphatase is inhibited by _________________________.
    fructose-2,6-bisphosphate
  194. The activity of phosphofructokinase-1 is inhibited by _______.
    citrate
  195. The activity of pyruvate kinase is inhibited by _______.
    alanine
  196. The activity of pyruvate dehydrogenase is inhibited by ______________________.
    enzyme phosphorylation
  197. The activity of fructose-1,6-bisphosphatase is increased by ________________.
    enzyme induction
  198. The activity of phosphofructokinase-1 is increased by _________________________.
    fructose-2,6-bisphosphate
  199. The activity of pyruvate kinase is increased by _________________________.
    fructose-1,6-bisphosphate
  200. The activity of pyruvate dehydrogenase is increased by ________________________.
    enzyme dephosphorylation
  201. The lower the negative ΔG number, the ______ the Keq.
    larger
  202. What are the three properties of free energy?
    • 1) Free energy is additive
    • 2) Free energy is reversible
    • 3) Free energy is multiplicative
  203. An exergonic reaction is any chemical reaction where the value of the equilibrium constant is __________________________________.
    a positive value greater than one
  204. An endergonic reaction is any chemical reaction where the value of the equilibrium constant is _______________________________.
    a positive value less than one
  205. When the value of ΔG0 for a chemical reaction is a negative number, the value of the corresponding equilibrium constant is ________________________________________.
    a positive value greater than one
  206. When the value of ΔG0 for a chemical reaction is a positive number, the value of the corresponding equilibrium constant is _____________________________.
    a positive value less than one
  207. What are the four oxidation-reduction steps in the tricarboxylic acid cycle?
    • 1) isocitrate ----> oxalosuccinate
    • 2) α-ketoglutarate ---> succinyl CoA
    • 3) succinate ---> fumarate
    • 4) L-malate ---> oxaloacetate
  208. What is the substrate-level phosphorylizaton step in the tricarboxylic acid cycle?
    succinyl CoA ---> succinate
  209. What is the yield of CO2 when 1 equivalent of glucose is completely catabolized by the combined activities of glycolysis, pyruvate dehydrogenase, and the TCA cycle?
    6 CO2
  210. How many CO2 molecules is produced in glycolysis?
    0 CO2
  211. How many CO2 molecules are produced in pyruvate dehydrogenase?
    2 CO2
  212. How many CO2 molecules are produced in TCA?
    4 CO2
  213. How many molecules of NADH and FADH2 is produced in glycolysis?
    2 NADH and 0 FADH2
  214. How many molecules of NADH and FADH2 are produced in pyruvate dehydrogenase?
    2 NADH and 0 FADH2
  215. How many molecules of NADH and FADH2 are produced in TCA?
    6 NADH and 2 FADH2
  216. How many pairs of electrons are found in each mobile electron carrier?
    2 pairs
  217. What is the yield of electrons when one equivalent of glucose is oxidized to 6 equivalents of CO2 by the combined activities of glycolysis, pyruvate dehydrogenase, and the TCA cycle?
    12 pairs
  218. What is the NET yield of substrate-level ATP equivalents when 1 equivalent of glucose is oxidized to 6 equivalents of CO2 by the combined activities of glycolysis, pyruvate dehydrogenase, and the TCA cycle?
    4 ATP
  219. How many ATP molecules are yielded in glycolysis?
    2 ATP
  220. How many ATP molecules are yielded in pyruvate dehydrogenase?
    0 ATP
  221. How many molecules of ATP are yielded in TCA?
    2 ATP
  222. What is the NET yield of ATP equivalents when 1 equivalents of glucose is oxidized to 6 equivalents of CO2 by the combined activities of glycolysis, pyruvate dehydrogenase, the TCA cycle, and electron transport/oxidative phosphorylation?
    32 ATP
  223. Assume that each NADH produced by the TCA cycle yields 2.5 ATP by oxidative phosphorylation. How many ATP will be produced from the NADH generated by one turn of the TCA cycle?
    7.5
  224. Assume that each FADH2 produced by the TCA cycle yields 1.5 ATP by oxidative phosphorylation. How many ATP will be produced from the FADH2 produced by one turn of the TCA cycle?
    1.5
  225. Assume that each NADH and/or each FADH2 produced by the TCA cycle represents a pair of electrons. How many pairs of electrons are produced by one turn of the TCA cycle?
    4
  226. So, how many total ATP are produced by oxidative phosphorylation after one turn of the TCA cycle?
    9
  227. Which reaction in the TCA cycle leads to a substrate level phosphorylation event?
    The ligase reaction
  228. Assume that the GTP produced by the TCA cycle is equivalent to an ATP. How many total high energy phosphoanhydride bonds (ATP + GTP) are produced by one turn of the TCA cycle?
    10
  229. Each molecule of pyruvate that is transformed by pyruvate dehydrogenase in the mitochondria yields one NADH, one CO2, and one acetyl-CoA. How many ATP are produced by oxidative phosphorylation if TWO equivalents of pyruvate are transformed to TWO equivalents of acetyl-CoA by the pyruvate dehydrogenase?
    5
  230. So, how many phosphoanhydride bonds (ATP + GTP) are produced by the complete oxidation of TWO molecules of pyruvate to carbon dioxide by the actions of pyruvate dehydrogenase and the TCA cycle in the mitochondria?
    25
Author
mcucullu
ID
40705
Card Set
Biochemistry Examination 2
Description
Notes for the upcoming pharmacy biochemistry exam.
Updated

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