5. Which of the following is     not correct     concerning 2,3-bisphosphoglycerate (BPG)?
(A) It binds at a distance from the heme groups of hemoglobin.
(B) It binds with lower affinity to fetal hemoglobin than to adult hemoglobin.
(C) It increases the affinity of hemoglobin for oxygen.
(D) It is an allosteric modulator.
(E) It is normally found associated with the hemoglobin extracted from red blood cells.

1. Choose the     correct     description. (A) Rhinoceros horn is hard and tough because it has high glucosamine content. (B) D-glucose is an anomer of L-glucose. (C) Lipoprotein is a dominant feature of the outer membrane of the cell wall of gram-negative bacteria. (D) Dithiothreitol could break the disulfide bond. (E) The peptide alanylglutamylglycylalanylleucine has five peptide bonds.

2. A repeating structural unit in a multimeric protein is known as a(n): (A) domain. (B) motif. (C) oligomer. (D) protomer. (E) subunit.

3. Please choose the correct answer from the following descriptions: (1) Amylose is unbranched; amylopectin and glycogen contain many (a1→4) branches. (2) Starch is the most abundant polysaccharide in nature. (3) Dextran is homopolysaccharide. (4) The galactose unit of the compound Gal(ẞ1→4)Glc residue is at the reducing end. (5) D-glucose and D-glucuronic acid is different on C6. (A) 1, 2, and 5 are     incorrect    . (B) 2 and 3 are correct. (C) 2 and 5 correct. (D) 1 and 3 are correct. (E) 1, 2, and 4 are     incorrect    .

4. Both water and glucose share an -OH that can serve as a substrate for a reaction with the terminal phosphate of ATP catalyzed by hexokinase. Glucose, however, is about a million times more reactive as a substrate than water. The best explanation is that: (A) Glucose has more -OH groups per molecule than does water. (B) The larger glucose binds better to the enzyme; it induces a conformational change in hexokinase that brings active-site amino acids into position for catalysis. (C) The -OH group of water is attached to an inhibitory H atom, while the glucose -OH group is attached to С. (D) Water and the second substrate, ATP, compete for the active site resulting in a competitive inhibition of the enzyme. (E) Water normally will not reach the active site because it is hydrophobic.

6. A monoclonal antibody differs from a polyclonal antibody in that monoclonal antibodies: (A) are labeled with chemicals that can be visualized. (B) are produced by cells from the same organism that produced the antigen. (C) are synthesized by a population of identical, or "cloned," cells. (D) are synthesized only in living organisms. (E) have only a single polypeptide chain that can recognize an antigen.

7. Which of the following statements of electron transport chain is     not true    ? (A) Complex I contains copper ions. (B) The final reduced species in the electron transport chain in mitochondria is H2O. (C) The P/O ratio refers to the number of moles of ATP produced for each mole of oxygen atoms consumed in electron transport. (D) Cytochrome c is a macromolecule which is loosely bound to the outer surface of the inner mitochondrial membrane. (E) None of the above.

8. Iron deficiency in a cell can adversely affect electron transport at which of the following sites: (A) Cytochrome b and cytochrome c. (B) Coenzyme Q and FADH2. (C) NADH and FADH2. (D) Coenzyme Q and NADH. (E) All sites in electron transport are affected.

9. Which one of the following statements about glycolysis is     correct    : (A) Conversion of glucose to glyceraldehyde-3-phosphate is an exergonic reaction. (B) Conversion of glucose-6-phosphate to fructose-6-phosphate is a cleavage reaction. (C) Conversion of glyceraldehyde-3-phosphate to give 1,3-bisphosphoglycerate is a dehydration reaction. (D) Conversion of dihyroxyacetone phosphate to glyceraldehyde-3-phosphate is an isomerization reaction. (E) Conversion of 2-phosphoglycerate to give phosphoenolpyruvate is an oxidation reaction.

10. Which one of the following is     not     associated with the oxidation of substrates by the citric acid cycle? (A) CO2 production. (B) Pyridine nucleotide oxidation. (C) Flavin reduction. (D) Lipoic acid present in some of the enzyme systems. (E) All of the above are involved.

11. Which one is     not     related with cardiovascular disease? (A) Cholesterol. (B) Caveolin. (C) Avastin. (D) HMG-CoA reductase. (E) Lovastatin.