6. The coenzyme ___ is the oxidizing agent in glycolysis.
NAD+
7. Which of the following is a potent activator of phosphofructokinase in mammals?
fructose-2,6-bisphosphate
9. Which of the following enzymes involved in gluconeogenesis reverses the reaction of hexokinase?
glucose-6-phosphatase
10. In eukaryotes, glycolysis typically occurs in the ___, gluconeogenesis typically occurs in the ___.
cytosol; cytosol
12. What type of bond forms when the hydroxyethyl group is transferred to lipoamide?
Thioester
13. In the citric acid cycle, what reduced cofactors are derived from the oxidation of one molecule of acetyl CoA to two molecules of CO2?
3 NADH and 1 QH2
14. How many electrons are transferred from on e acetyl group when it is converted to two carbon dioxide molecules in the citric acid cycle?
8
15. Where is succinate dehydrogenase located?
mitochondrial inner membrane
16. What does the reduction potential of 0.815V for the reduction of oxygen to water indicate?
oxygen is a very strong oxidizing agent
17. Which of the following statements about reduction potentials is FALSE?
the more negative the value the greater the tendency to be reduced.
18. How many protons are transported from the matrix to the intermembrane space by Complex I?
4
19. Complex III accepts electrons from ___ and transfers them to ___.
ubiquinol; cytochrome c
20. How many protons are transported from the matrix to the intermembrane space by Complex II?
0
21. Complex IV uses ___ and ___ ions to reduce oxygen to water.
copper; iron
22. How many molecules of NADPH are produced per glucose molecule processed by the pentose phosphate pathway?
2
23. Which of the following is mobilized for energy use by a phosphorolysis reaction rather than by hydrolysis
glycogen
28. Glyceraldehyde is oxidized to ___ which can transfer a phosphate to ___.
1,3-bisphosphoglycerate; ADP
31. In the muscle, when a residue of glucose is cleaved from glycogen and converted to pyruvate via glycolysis, what is the net ATP production (beginning with glycogenolysis)?
3
32. In the event that NADPH is needed but ribose is not, which of the following is an end product of the pentose phosphate pathway?
glyceraldehyde-3-phosphate
33. Both glycogen synthesis and glycogen breakdown share the metabolite ___.
glucose-1-phosphate
35. During glycolysis, the steps between glucose and formation of the triose phosphates.
consume two ATP molecules
36. Fill in the missing reagents in the following reaction.
reactant: NADH + H+; product: NAD+
37. Which of the following coenzymes is directly responsible for the oxidation of the hydroxyethyl group to the acetyl group?
lipoamide
40. ___ is the first compound that is oxidized in the citric acid cycle.
isocitrate
41. ___ is an enzyme that catalyzes a substrate-level phosphorylation
succinyl-CoA synthetase
42. Which enzyme of the pyruvate dehydrogenase complex is responsible for regenerating an oxidized lipoamide cofactor?
E3
43. Which of the following pyruvate dehydrogenase enzymes is correctly paired with the coenzyme with which it is associated?
E3: FAD
49. If an ATP synthase has 12 c subunits, how many protons must move through the enzyme to produce one ATP?
4
50. Which of the following occurs when the catalytic subunit of ATP synthase is in the loose state?
ADP and Pi bind
51. The reduction potentials of all prosthetic groups of Complex I have reduction potentials between ___ and ___.
NAD+; ubiquinone
52. What can be said abut this reaction when the concentration of 2-phophoglycerate is 0.481mM and the concentration of 3-phosphoglycerate is 2.90mM at 25C
This reaction is at equilibrium under these conditions.
53. PPC is allosterically activated by ____.
A and B
54. Malonate is a competitive inhibitor of succinate dehydrogenase. What citric acid cycle intermediates accumulate if malonate is present in a preparation of isolated mitochondria
A,B,C
55. What would be the predicted energy yield of ATP from glycolysis in a patient with a defect in triosephosphate isomerase?
0 ATP
56. .........what is the efficiency for energy captured in the proton gradient versus energy evolved from NADH oxidation?
91%
57. Considering your answer to this question, will the reaction proceed under normal cellular conditions?
[dihydroxyaceton phosphate] > [glyceraldehyde-3-phosphate]; reaction WILL proceed