44. Which of the following substrates cannot contribute to net gluconeogenesis in mammalian liver?
(A) Alanine
(B) Glutamate 
(C) Palmitate  
(D) Pyruvate
(E) a-ketoglutarate

40. Which of the following enzymes catalyzes the conversion shown below in the glycolysis pathway? (A) Hexokinase (B) Phosphofructokinase-1 (PFK-1) (C) Phosphohexose isomerase (D)Phosphoglucose mutase (E) Phosphohexose epimerase

41. The reaction, 1,3-bisphosphoglycerate→ 2,3-bisphosphoglycerate, is catalyzed by: (A) bisphosphoglycerate phosphatase (B) bisphosphoglycerate mutase (C) 2,3-bisphosphoglycerate synthetases (D) 3-phosphoglycerate isomerase (E) 1,3-bisphosphoglycerate hydrolase

42. 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.

43. In the citric acid cycle, succinate is dehydrogenated by succinate dehydrogenase, which yields fumarate. The dehydrogenation of two of the four hydrogens in succinate (labeled as H1~H4 in the figure shown below) is stereospecific, with the pro-S hydrogen removed from one carbon atom and the pro-R hydrogen removed from the other.  Which of the following two hydrogens could be abstracted in the four hydrogens of the succinate molecule in the reaction catalyzed by succinate dehydrogenase? a. H1 and H2 b. H1 and H3 c. H1 and H4 d. H2 and H3 e. H2 and H4 f. H3 and H4 (A) b and e (B) c and d (C) a and f (D) Only c could occur. (E) Only d could occur.

45. Glucose, labeled with in different carbon atoms, is added to a crude extract of a tissue rich in the enzymes of the pentose phosphate pathway. The most rapid production of will occur when the glucose is labeled in: (A) C-1. (B) C-3. (C) C-4. (D) C-5. (E) C-6.

46. Which of these statements is true? (A) Integral membrane proteins usually contain one or more regions with a high hydropathy index. (B) In integral membrane proteins, the domains that protrude on the cytoplasmic face of the plasma membrane nearly always have covalently attached oligosaccharides. (C) A hydropathy plot is used to extrapolate for the true molecular weight of a membrane protein. (D) A hydropathy plot is used to deduce the quaternary structure of a membrane protein. (E) A hydropathy plot is used to determine the water-solubility of a protein.

47. The following fatty acid, in which the indicated carbon is labeled with , is fed to an animal: After a period of time for fatty acid β oxidation, the label would most likely be recovered in: (A) acetyl-CoA. (B) beta-hydroxy butyryl-CoA. (C) both acetyl-CoA and propionyl-CoA. (D) palmitoyl-CoA. (E) propionyl-CoA.

48. Which types 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.

49. The following molecular structure is the disaccharide maltose. Which position could be oxidized by the use of Fehling's reagent?  (A) No. 1. (B) No. 2. (C) No. 3. (D) No. 4. (E) No. 5.

50. Oxaloacetate uniformly labeled with (i.e., with equal amounts of in each of its carbon atoms) is condensed with unlabeled acetyl-CoA. After a single pass through the citric acid cycle back to oxaloacetate, what fraction of the original radioactivity will be found in the oxaloacetate? (A) All (B) 1/2 (C) 1/3 (D) 1/4 (E) 3/4