17. In an anaerobic muscle preparation, lactate formed from glucose labeled in C-3 and C-4 would be labeled in:
(A) all three carbon atoms.
(B) only the carbon atom carrying the OH.
(C)only the carboxyl carbon atom.
(D) only the methyl carbon atom.
(E) the methyl and carboxyl carbon atoms.

13. Which of the following statements about a plot of Vo vs. [S] for an enzyme that follows Michaelis-Menten kinetics is false? (A) As [S] increases, the initial velocity of reaction Vo also increases. (B) At very high [S], the velocity curve becomes a horizontal line that intersects the y-axis at Km. (C)Km is the [S] at which V0 = 1/2 Vmax. (D) The shape of the curve is a hyperbola. (E) The y-axis is a rate term with units of µm/min.

14. Which of the following monosaccharides is not an aldose? (A) erythrose (B) fructose (C)glucose (D) glyceraldehyde (E) ribose

15. From the abbreviated name of the compound Gal(β1 → 4)Glc, we know that: (A) C-4 of glucose is joined to C-1 of galactose by a glycosidic bond. (B) the compound is a D-enantiomer. (C)the galactose residue is at the reducing end. (D) the glucose is in its pyranose form. (E) the glucose residue is the β anomer.

16. In the laboratory, recombinant plasmids are commonly introduced into bacterial cells by: (A) electrophoresis – a gentle low-voltage gradient draws the DNA into the cell. (B) infection with a bacteriophage that carries the plasmid. (C)microinjection. (D) mixing plasmids with an extract of broken cells. (E) transformation - heat shock of the cells incubated with plasmid DNA in the presence of CaCl2.

18. Glucose labeled with 14C in C-1 and C-6 gives rise in glycolysis to pyruvate labeled in: (A) A and C. (B) all three carbons. (C)its carbonyl carbon. (D) its carboxyl carbon. (E) its methyl carbon.

19. Inorganic fluoride inhibits enolase. In an anaerobic system that is metabolizing glucose as a substrate, which of the following compounds would you expect to increase in concentration following the addition of fluoride? (A) 2-phosphoglycerate (B) Glucose (C)Glyoxylate (D) Phosphoenolpyruvate (E) Pyruvate

20. The glycogen-branching enzyme catalyzes: (A) degradation of (α1 → 4) linkages in glycogen (B) formation of (α1 → 4) linkages in glycogen. (C)formation of (α1 → 6) linkages during glycogen synthesis. (D) glycogen degradation in tree branches. (E) removal of unneeded glucose residues at the ends of branches.

21. Glycogen phosphorylase a can be inhibited at an allosteric site by: (A) AMP. (B) calcium. (C)GDP. (D) glucagon. (E) glucose.

22. Which of the below is not required for the oxidative decarboxylation of pyruvate to form acetyl-CoA? (A) ATP (B) CoA-SH (C)FAD (D) Lipoic acid (E) NAD+

23. Which of the following is not an intermediate of the citric acid cycle? (A) Acetyl-CoA (B) Citrate (C)Oxaloacetate (D) Succinyl-CoA (E) α-Ketoglutarate