BiochemistryMock Exam 2Perry Griffin

  1. When oxygen is binding to myoglobin, we see a _____ curve which tells us that when the concentration of oxygen is much less than P50, _____ O2 _____ MbO2.
  2. Sigmoidal; increasing; increases
  3. Hyperbolic; decreasing; decreases
  4. Sigmoidal; decreasing; decreases
  5. Hyperbolic; increasing; increases
  6. Both A and B
  1. The P50 value of O2 binding to Hb is _____ than that of Mb meaning that oxygen tends to bind to _____ better.
  1. Less than; Mb
  2. More than; Hb
  3. Equal to; Mb
  4. Equal to; Hb
  5. None of the above
  1. The cooperative model of oxygen binding exhibited in _____ demonstrates its ability to _____ bind the initial oxygen while _____ binding the last oxygen.
  1. Hb; weakly; tightly
  2. Mb; weakly; tightly
  3. Hb; tightly; weakly
  4. Mb; tightly; weakly
  5. Hb; weakly; weakly
  1. In the Bohr shift, the Hb binding curve shifts _____ as the pH decreases from 7.6 to 7.2.
  1. Left
  2. Right
  3. Up
  4. Down
  5. North by Northwest
  1. ATP is composed of ____ phosphoanhydride bond(s) and ____ phosphoester bond(s). There is/are also ____ mixed anhydride bonds that give ATP its energy-payload.
  2. 1;2;1
  3. 3;0;2
  4. 0;3;1
  5. 2;1;2
  6. none of the above
  1. The standard free energy change for pyrophosphate hydrolysis to 2Pi is ____ (kJ/mol).
  2. -20 to -30
  3. -30 to -40
  4. -20 to -30
  5. -30 to -40
  6. none
  1. The standard free energy change Glycerol-3-Pi to Glycerol+Piis ____ (kJ/mol).
  2. 0 to -10
  3. -10 to -20
  4. -20 to -30
  5. -30 to -40
  6. -50 to -60
  1. ATP has a maximum negative charge of ____ while PPPi has a negative charge of ____.
  2. -3; -4
  3. -5; -4
  4. -4; -5
  5. -4; -3
  6. none
  1. The hydrolysis of free energy of phosphoenolpyruvate is about ____ kJ/mol (closest answer).
  2. 0 to -10
  3. -10 to -20
  4. -20 to -30
  5. -30 to -40
  6. -50 to -60
  1. The previous question has the free energy that it does due to the ____ bond present in PEP.
  2. Phosphoester
  3. Phosphoanhydride
  4. Mixed anhydride
  5. Phosphodiester
  6. None
  7. Rank the concentration of the adenine nucleotides for their presence in a cell and at equilibrium, respectively.
  8. [ADP]>[ATP]>[AMP]; [ADP]>[AMP]>[ATP]
  9. [AMP]>[ADP]>[ATP]; [ATP]>[ADP]>[AMP]
  10. [ATP]>[AMP]>[ADP]; [ATP]>[ADP]>[AMP]
  11. [ATP]>[ADP]>[AMP]; [AMP]>[ADP]>[ATP]
  12. none
  1. At equilibrium, the reactants in the reaction AMP + PiADP + H2O and ADP + PiATP + H2O are ____ times more abundant than the products. This means that in the reaction AMP + 2PiATP + H2O, AMP is ____ times more abundant than ATP.
  2. 108; 106
  3. 1012;106
  4. 106; 1012
  5. 106; 108
  6. None
  1. In the enzyme-mediated reaction of S P, there is an increase in the velocity of the reaction though there is a(an) ____ in ΔGo that results in a(an) ____ in the formation of S from P.
  2. Decrease; increase
  3. Increase; decrease
  4. No change; increase
  5. No change; decrease
  6. None
  1. When all other condition are the same, the activation energy of an enzyme mediated reaction will always be ____ than that of an unmediated reaction.
  2. Higher
  3. Lower
  4. Depends on the enzyme class
  5. Depends on the temperature
  6. Depends on the pH and the temperature
  1. ____ is the enzyme class that catalyzes the removal of water by the formation of a double bond.
  2. Oxidoreductase
  3. Ligase
  4. Lyase
  5. Hydrolase
  6. None
  1. ____ is the enzyme class that can move a group from one molecule to another. ____ is an example of an enzyme from this group that can ____ a phosphate group onto another molecule from ATP.
  2. Oxidoreductase; kinase; add
  3. Lyase; phosphatase; remove
  4. Lyase; kinase; remove
  5. Transferase; kinase; add
  6. Transferase; kinase; remove
  1. The conversion of acetaldehyde to ethanol is mediated by a(an) ____ enzyme (class) using the ____ cosubtrate. This reaction ____ spontaneous.
  2. Oxidoreductase; NADH; is not
  3. Oxidoreductase; NAD+; is
  4. Transferase; NADH; is
  5. Transferase; NAD+; is not
  6. None
  1. In the conversion of D-glyceraldehyde to dihydroxyacetone, the ____ enzyme class is used.
  2. Transferase
  3. Isomerase
  4. Lyase
  5. Hydrolase
  6. None
  1. The oxidation number of the carbon atom in –CO2- is ____ while it is ____ in the -CHOH- group.
  2. 0; 0
  3. +4; +2
  4. +3; 0
  5. 0; +3
  6. +2; +4
  1. The change in oxidation number of the carbon in an aldehyde functional group and the carbon in a carboxylate functional group is ____.
  2. -1
  3. 0
  4. 1
  5. 2
  6. 3
  1. The ____ step of the mechanism of a Michaelis-Menten (MM) enzyme is the slowest step. As a result, ____ happens here and ____ is formed.
  2. Second; binding; S+E
  3. First; binding; EP
  4. Second; chemistry; S+E
  5. Third; release; ES
  6. Second; chemistry; EP
  1. The reaction velocity for X+YZ quadruples when either [X] is doubled or [Y] is quadrupled. This reaction is ____ order for X and ____ order for Y and ____-order overall.
  2. 2;4;4
  3. 4;2;6
  4. 1;2;3
  5. 2;1;3
  6. None
  1. When [S]> Km for a MM enzyme, the rxn velocity is ____ order for [S] and it approaches ____. When [S]<Km for a MM enzyme, the rxn velocity is ____ order for [S] and tend to ____ linearly
  2. 1st; Vmax/Km; 0th ; increase
  3. 0th; Km/Vmax; 1st; decrease
  4. 1st; Vmax; 0th; decrease
  5. 0th; Vmax; 1st; increase
  6. none
  1. For a MM enzyme, catalytic perfection is achieved when ____ approaches 108 (M-1S-1).
  2. Km
  3. 1/Vmax
  4. kcat/Km
  5. Vmax/Km
  6. Either A or C
  1. Competitive inhibitors of a MM enzyme bind to ____ and have ____ Vmax’s. Noncompetitive inhibitors, however, will ____ Vmax.
  2. E; lower; higher
  3. ES; higher; lower
  4. E; non-changing; lower
  5. E; non-changing; higher
  6. ES; non-changing; lower
  1. When the kinetic data of a MM enzyme is plotted as a double reciprocal plot, it is called a Lineweaver-Burk plot. These plots transform ____ data to ____ data. The Y-intercepts of these graphs are ____.
  2. Hyperbolic; linear; -1/Km
  3. Sigmoidal; linear; 1/Vmax
  4. Hyperbolic; linear; 1/Vmax
  5. Linear; hyperbolic; -1/Km
  6. Either B or C depending on the situation
  1. Allosteric enzymes exhibit ____ velocity curves where activation implies a shift to the ____ and inhibition implies a shift to the ____.
  2. Linear; right; left
  3. Hyperbolic; left; right
  4. Sigmoidal; right; left
  5. Sigmoidal; left; right
  6. Hyperbolic; right; left
  1. The most significant metabolic flux in the forward direction of AP occurs when Q/Keqis____. For the reverse reaction of the above process, the ratio of Keq/Q of ____ provides the most flux.
  2. 10-6;10-4
  3. 10-12;10-6
  4. 10-2;10-4
  5. 10-4;10-2
  6. Either B or D
  1. Given that ΔGo = RT , the most forward reaction with the greatest driving force would have which of the following ratios for Q/Keq?
  2. 108
  3. 1012
  4. 10-8
  5. 10-12
  6. Either B or D
  1. Which of the following ΔG’ values has the greatest tendency to achieve equilibrium?
  2. -20
  3. -40
  4. 5
  5. 40
  6. Both B and D
  1. During vigorous muscle contraction, ____ stores the chemical energy necessary to rapidly regenerate ATP.
  2. Creatine
  3. Creatine-Pi
  4. PEP
  5. ADP
  6. Either A or B
  1. In cells, ATP is ____ times more prevalent than AMP.
  2. 5
  3. 106
  4. 1/5
  5. 10-6
  6. 50
  1. In the net reaction of glycolysis, there are ____ pyruvate produced and ____ ATP produced.
  2. 1;1
  3. 2;2
  4. 1;2
  5. 2;1
  6. 1;0
  1. In glycolysis, fructose-6-phosphate is converted to F-1,6-BP using a ____ enzyme (class), specifically a ____.
  2. Ligase; phosphatase
  3. Transferase; kinase
  4. Ligase; kinase
  5. Transferase; phosphatase
  6. None
  1. In glycolysis, each glycerate-1,3-bisphosphate is converted to pyruvate and ____ ATP using ____ rxn steps.
  2. 1;3
  3. 1;4
  4. 2;3
  5. 2;4
  6. None
  1. In glycolysis, which reaction(s) consume(s) or produce(s) ATP and contribute to metabolic flux?
  2. 3
  3. 1 and 3
  4. 7 and 10
  5. 1,3, and 7
  6. 1, 3, and 10
  1. Reaction 10 of glycolysis converts ____ to pyruvate. It utilizes a ____ bond and ____ spontaneous.
  2. 2-phospohoglycerate; phosphoester; is
  3. PEP; phosphoester; is
  4. 2-phospohoglycerate; phosphoester; is not
  5. PEP; phosphoanhydride; is not
  6. PEP; phosphoanhydride; is
  7. The net metabolic flux generated for the reaction of glucose  2pyruvate is approximately ____ kJ/mol. This net reaction ____ spontaneous
  8. -50; is
  9. -60; is
  10. -70; is
  11. 70; is not
  12. 60; is not
  1. Reaction ____ of glycolysis is the only reaction to utilize a dehydrogenase enzyme. It converts ____ to 1,3-BPG. This reaction ____ near equilibrium.
  2. 1; glyceraldehyde-3-phosphate; is
  3. 6; glyceraldehyde-3-phosphate; is not
  4. 3; glyceraldehyde-3-phosphate; is
  5. 1; 3-phosphoglycerate; is not
  6. 6; glyceraldehyde-3-phosphate; is
  1. Glycogen branches using _____ glycosidic bonds that result in more _____ ends; these brances occur ~ every _____ residues.
  2. α(14); reducing; 2
  3. α(16); non-reducing; 4
  4. α(14);non-reducing; 4
  5. α(16); reducing; 2
  6. none
  1. Glycogen biosynthesis _____ to metabolic flux while it’s degradation _____.
  2. Does not contribute; does
  3. Contributes; does not
  4. Contributes; contributes
  5. Does not contribute; does not
  6. None
  1. In the net reaction of glycogen degradation, glycogen phosphorylase produces _____ while phosphoglucomutase produces _____.
  2. Glucose-1-P; Glucose-1,6-BP
  3. Glucose-1-P; Glucose-6-P
  4. Glucose-1,6-BP; Glucose-6-P
  5. A and B
  6. B and C
  1. In the intestine, glycosidases, which are _____ , break down starches into their _____ substrates that can be absorbed by the intestinal mucosa.
  2. Phsophorylases; disaccharide
  3. hydrolases; disaccharide
  4. Phsophorylases; monosaccharide
  5. hydrolases; monosaccharide
  6. none
  1. In a well-fed metabolic state, serum _____ is taken up by all cells.
  2. Glucose-6-P
  3. Glucose
  4. Glucose-1-P
  5. UDP-glucose
  6. None
  1. The conversion of Glucose to UDP-Glucose cleaves _____ phosphoanhydride bonds and makes _____ phosphoanhydride bonds.
  2. 1; 2
  3. 0; 2
  4. 2; 1
  5. 2; 0
  6. none
  1. When blood glucose levels are high, _____ is released into the blood and glycogen synthase is _____.
  2. Insulin; is phosphorylated
  3. Insulin; is dephosphorylated
  4. Glucagon; is phosphorylated
  5. Glucagon; is dephosphorylated
  6. None