44. Which of the following enzymes catalyzes the conversion shown below?
(A) Hexose isomerase
(B) UDP-galactose 4-isomerase
(C) UDP-galactose 4-mutase
(D) Phosphoglucose mutase
(E) UDP-glucose 4-epimerase

40. The citric acid (CA) cycle is considered part of aerobic metabolism even though oxygen does not appear explicitly in any reaction because: (A) it takes place in the mitochondrion. (B) it contains oxidation reactions. (C) the NADH and FADH2 produced are reoxidized in the electron transport chain linked to oxygen. (D) the reoxidation of NADH and FADH2 leads to the production of considerable quantities of ATP. (E) None of above is correct.

41. Which of the following statements about the Calvin cycle (CC) is correct? (A) CC is present in all photosynthetic eukaryotes and also many photosynthetic bacteria. (B) Reactions in CC utilize CO2, ribulose-1,5-bisphosphate to synthesize glucose. (C) Many reshuffling reactions in CC are like those of the pentose phosphate pathway. (D) Many reactions in CC involve transaldolase and transketolase. (E) All of above are correct.

42. _____ is often used in carboxylation reactions while _____ is often used in decarboxylation reactions. (A) thiamine pyrophosphate; lipoate (B) lipoate; biotin (C) biotin; thiamine pyrophosphate (D) pyridoxal-5-phosphate; biotin (E) lipoate; pyridoxal-5-phosphate

43. All are uses of glucose-6-phosphate in liver   except  : (A) catabolized to acetyl-CoA for fatty acid biosynthesis. (B) generate NADPH and pentoses. (C) released as glucose to blood stream. (D) converted to glycogen. (E) All are true.

45. All of the following are fuels for contracting muscles during strictly anaerobic metabolism   except  : (A) ATP. (B) creatine phosphate. (C) glycogen. (D) glucose. (E) palmitic acid.

46. Which of the followings best describes the glycosidic bond below? (A) β(2-4) (B) α(1-3) (C) α(1-4) (D) β(1-4) (E) α(2-4)

47. Which type of columns are affected by the ionic charge, shape, substrate-binding strength of a protein, respectively? (A) Gel filtration, Affinity chromatography, Cation or anion exchange. (B) Affinity chromatography, Gel filtration, Cation or anion exchange. (C) Cation or anion exchange, Gel filtration, Affinity chromatography. (D) Gel filtration, Cation or anion exchange, Affinity chromatography. (E) Cation or anion exchange, Affinity chromatography, Gel filtration.

48. 2,4-Dinitrophenol and oligomycin inhibit mitochondrial oxidative phosphorylation. 2,4-Dinitrophenol is an uncoupling agent; oligomycin blocks the ATP synthesis reaction itself. Therefore, 2,4-dinitrophenol will: (A) allow electron transfer in the presence of oligomycin. (B) allow oxidative phosphorylation in the presence of oligomycin. (C) block electron transfer in the presence of oligomycin. (D) diminish O2 consumption in the presence of oligomycin. (E) None of the above.

49. All are physiological changes initiated by glucagon   except  : (A) activation of glycogenolysis in liver. (B) stimulation of liver gluconeogenesis. (C) long-term maintenance of steady-state levels of glucose in the blood stream. (D) activation of glycogenolysis in muscles. (E) All are true.

50. A molecule such as 2,4-dinitrophenol (2,4-DNP) works to uncouple the proton gradient. Which of the following is true about 2,4-DNP? (A) 2,4-DNP is protonated in the matrix and deprotonated in the intermembrane space. (B) The presence of an uncoupler results in an increase in the activity of the TCA cycle and electron transport. (C) 2,4-DNP is a very ineffective uncoupler because its hydrophobic structure prevents it from effectively crossing lipid bilayer membranes. (D) 2,4-DNP has been used as a very effective diet aid for the past 70 years. (E) None of the above is correct.