Biochemistry 305, Fall 2013: Exam 11. The following chemical transformation is an example of what type of reaction?a. Additionb. Eliminationc. Isomerizationd. Nucleophilic substitutione. Oxidation reduction2. Which force is not a weak force?a. Hydrogen bondsb. Van der Waals interactionsc. Covalent bondsd. Ionic interactionse. Hydrophobic interactions3. Which of the statements about the nature of the hydrogen bond is FALSE?a. The donor is a hydrogen atom bonded to an atom that is more electronegative than hydrogenb. The more linear the bond, the stronger the interactionc. The acceptor must be more electronegative than hydrogend. It is a type of non-covalent bond.e. A hydrogen bond is a type of hydrophobic interaction4. Which statement about hydrophobic interactions is TRUE?a. They lead to the clustering of non-polar molecules when added to an aqueous solutionb. They result because water molecules prefer to hydrogen bond with non-polar molecules. c. They result from ionic interactions between water and non-polar moleculesd. They are a major force that stabilizes primary structure in proteinse. They result in polar and charged regions of biological molecules being buried in the molecule’s interior, excluding those regions fromthe aqueous environment5. Which of these statements about the properties of water is FALSE?a. Ability to form hydrogen bonds.b. High dielectric constant enables solvation of ions. c. Ability to orient around non-polar solutes to promote hydrophobic interactionsd. Can dissociate to form H+ and OH- ions.e. None, all are true.6. Ice is less dense than liquid water because ___________.a. The hydrogen bonds are longer in ice.b. Water has a lower dipole moment at low temperaturesc. The hydrogen bonds are unable to form in ice COO-HC OH CH COO-COO-CHCHCOO-+ H2Od. The half-life of hydrogen bonds is shorter in ice.e. Water is unable to dissociate into H+ and OH- at low temperatures7. The pH of pure water is _____:a. 0b. 7c. 7.4d. 14e. 55.58. Grapefruit juice (pH 3.2) contains _____ times as much H+ as orange juice(pH 4.3)?a. 0.74b. 7.9 x 10-2c. 110d. 12.6e. 1.349. The pH of a 0.166 M monoprotic acid solution is 6.09. What is the pKa of the monoprotic acid?a. 0.78b. 5.92c. 6.26d. 8.13e. 11.410.Which of the following is NOT an intrinsic property of ALL 20 standard amino acids?a. Chiralb. The capacity of polymerizec. Acid-base chemistryd. Varied structure and chemical functionality in side chainse. Act as polyprotic acids11.Which of the following amino acids is classified as a basic amino acid?a. Leucineb. Phenylalaninec. Aspartatic acidd. Asparaginee. Lysine12.Which amino acid is shown here?a. Aspb. Valc. Alad. Sere. Leu13.Which amino acid lacks BOTH a free alpha-amino and a free alpha-carboxyl group?a. Aspartic acidb. LysineHCCH OC OHH NHH3C CH3c. Asparagined. Prolinee. Valine14.At what pH value would Histidine have a net negative charge?a. 1.0b. 4.0c. 6.0d. 8.0e. 11.015.Calculate the isoelectric point for glutamic acid.a. 2.20b. 3.25c. 4.30d. 5.95e. 7.0016.What feature of the peptide bond limits rotational movement around the C-N bond?a. Hydrogen bonding between the carbonyl and the alpha-carbonb. Electrostatic attraction between COO- and NH3+ groupsc. Electrostatic repulsion from adjacent COO- groupsd. Steric hindrance from side groupse. Partial double bond character17.What is the overall net charge of the peptide K-K-N-Ea. +2b. +1c. 0d. -1e. -218.An ionic interaction could occur within a protein between the R groups of which pair of amino acids at physiological pH?a. Asp/Glub. Val/Leuc. Tyr/Cysd. Arg/Lyse. Lys/Glu19.A common reaction of 2 Cys residues in proteins results in the formation of _________.a. Thioester bondsb. Disulfide bondsc. Dithiol bondsd. Thioether bondse. Hydrogen bonds20.Alpha-helices and Beta-sheets are components of what level of protein structure?a. Primaryb. Secondaryc. Tertiaryd. Quaternary21.Formation of a trimer would be an example of what level of protein structure?a. Primaryb. Secondaryc. Tertiaryd. Quaternary22.Alpha-helices are stabilized primarily by _________________a. Hydrogen bonds between the main chain peptide bond component atomsb. Electrostatic interactions between R-groupsc. Hydrophobic interactions between the alpha-carbons of the main chaind. Hydrogen bonds between the R-groupse. Hydrophobic interactions between R-groups and the solvent water.23.Which protein(s) will bind strongly to an anionic exchange column at pH 7.5?a. Bb. Cc. Dd. A and Ce. B and D24.Which mutation would be LEAST likely to impact the folding and/or function of the protein?a. Lys to SerProtein A 236 kD pI of 8.4Protein B 22 kD pI of 6.3Protein C 68 kD pI of 9.7Protein D 43 kD pI of 7.5b. Ala to Aspc. His to Prod. Val to Ilee. Phe to Tyr25.To fold properly, a peptide absolutely requires which of the following:a. Chaperonesb. Non-reducing conditionsc. Aqueous environmentd. Both a and ce. Both b and c26.Pellagra is the result of a deficiency in what amino acid?a. Tyrosineb. Lysinec. Phenylalanined. Threoninee. Tryptophan27.Which statement is FALSE about prokaryotic cells?a. Some have a flagellab. All have a plasma membranec. All have nucleusd. All have ribosomese. All lack mitochondria28.A mixture of proteins is loaded onto a gel filtration column with a sizing range of 40-150 kD. In what order will the proteins be eluted from the column (first to last)?a. C, A, D, Bb. B, D, A, Cc. A, C, D, Bd. B, D, C, Ae. B, D, A, CProtein A 236 kD pI of 8.4Protein B 22 kD pI of 6.3Protein C 68 kD pI of 9.7Protein D 43 kD pI of
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