Final Exam (Chapters 7-12, 17, 19)

4. Likely the most ancient of the metabolic pathways in which energy is released from glucose and captured in the form of ATP under anaerobic conditions is called: a. photooxidation. b. oxidative phosphorylation. c. citric acid cycle. d. glycolysis. e. none of the above.

d. glycolysis.

24. Eukaryotic mRNAs are synthesized in the nucleus, are called ____, and contain noncoding regions called ____ because they intervene between coding regions called ____. a. poly A RNAs; noncodons; codons b. poly A RNAs; intervening sequences; codons c. heterogeneous nuclear RNAs; intervening sequences (introns); codons d. heterogeneous nuclear RNAs; intervening sequences (introns); exons e. none of the above.

d. heterogeneous nuclear RNAs; intervening sequences (introns); exons

25. Plant sterols are: a. so similar to cholesterol that they undergo the same physiology and metabolism. b. different isomers of cholesterol at the double bond location only. c. to be avoided in your diet because they elevate blood cholesterol levels. d. highly effective in blocking the absorption of cholesterol by intestinal cells. e. none are true.

d. highly effective in blocking the absorption of cholesterol by intestinal cells.

28. Mucopolysaccharides such as ____ form protective coats on animal cells. a. chitin b. cellulose c. glycogen d. hyaluronic acids e. glucuronic acids

d. hyaluronic acids

15. Which enzymes of the TCA cycle catalyze oxidative decarboxylation reactions? a. malate dehydrogenase and citrate synthase b. fumarase and succinate dehydrogenase c. α-ketoglutarate dehydrogenase and succinate dehydrogenase d. isocitrate dehydrogenase and α-ketoglutarate dehydrogenase e. aconitase and succinate dehydrogenase

d. isocitrate dehydrogenase and α-ketoglutarate dehydrogenase

24. Characteristics of succinate dehydrogenase include all EXCEPT: a. it is also known as succinate-Coenzyme Q reductase. b. it has covalently bound FAD. c. it is a membrane-bound enzyme. d. it removes hydrogens from C-O bonds. e. it carries out either 1-electron or 2-electron transfers to/from FAD.

d. it removes hydrogens from C-O bonds.

38. Which of the following is a result of a high fat, high protein, low carbohydrate diet? a. the bloodstream has a healthy level of ketone bodies b. glycogen stores are close to maximum capacity c. the brain operates most efficiently on this type of diet d. ketone body production generally exceeds rate of elimination e. none of the above

d. ketone body production generally exceeds rate of elimination

8. Citrate synthase has a ____ ΔG°′ and is essentially ____ due to the ____ of the CoA thioester. a. large positive; reversible; oxidation b. nearly zero; reversible; reduction c. nearly zero; irreversible; reduction d. large negative; irreversible; hydrolysis e. large negative; reversible; hydrolysis

d. large negative; irreversible; hydrolysis

3. Dietary essential fatty acids for humans include a. γ-linolenic and oleic acids. b. oleic and linoleic acids. c. palmitic and oleic acids. d. linoleic and γ-linolenic acids. e. all are true.

d. linoleic and γ-linolenic acids.

6. Diets aimed at reducing coronary heart disease should be: a. low in trans-fatty acids and high in saturated fatty acids. b. high in trans-fatty acids and high in saturated fatty acids. c. high in trans-fatty acids and low in saturated fatty acids. d. low in trans-fatty acids and low in saturated fatty acids. e. low in trans-fatty acids and low in unsaturated fatty acids.

d. low in trans-fatty acids and low in saturated fatty acids.

15. The porin proteins (e.g., maltoporin) utilize the ____ structural motif. a. single transmembrane α-helix b. multiple transmembrane α-helixes c. single β-sheet d. multiple β-sheet e. none of the above

d. multiple β-sheet

23. In vitro ____ makes it possible to alter the nucleotide sequence of a cloned gene systematically. a. protein synthesis b. mRNA synthesis c. hybridization d. mutagenesis e. all are true

d. mutagenesis

28. One advantage of nuclear magnetic resonance (NMR) spectroscopy for the investigation of metabolism is that it utilizes: a. radioisotopes. b. specific metabolic inhibitors. c. autoradiography. d. non-invasive techniques. e. none are true.

d. non-invasive techniques.

30. The oxidation of malate to oxaloacetate is not thermodynamically favored under standard conditions. It occurs because: a. it involves substrate-level phosphorylation. b. it is coupled with a strong reduction. c. it is coupled with ATP hydrolysis. d. oxaloacetate is used in the next reaction, which has a negative ΔG. e. the previous reaction has a large negative ΔG.

d. oxaloacetate is used in the next reaction, which has a negative ΔG.

12. Certain phospholipids, including ____ and ____, participate in complex cellular signaling events. a. phosphatidylcholine; phosphatidylserine b. phosphatidylserine; phosphatidylalanine c. phosphatidylcholine; phosphatidylglycerol d. phosphatidylinositol; phosphatidylcholine e.phosphatidylethanolamine; phosphatidylserine

d. phosphatidylinositol; phosphatidylcholine

17. Naturally occurring, self-replicating, extra-chromosomal DNA molecules found in bacteria that carry genes specifying novel metabolic capacity advantageous to the bacterium are called: a. probes. b. cruciform. c. toroidal DNA. d. plasmids. e. all of the above.

d. plasmids.

40. Mammalian pyruvate dehydrogenase is regulated by phosphorylation using the enzyme ____ which is allosterically activated by high levels of ____ and ____. a. pyruvate kinase; ATP; acetyl-CoA b. pyruvate kinase; NADH; NADPH c. pyruvate carboxylase; acetyl-CoA; ATP d. pyruvate dehydrogenase kinase; NADH; acetyl-CoA e. pyruvate dehydrogenase kinase; ADP; NAD+

d. pyruvate dehydrogenase kinase; NADH; acetyl-CoA

19. α-Ketoglutarate dehydrogenase is a multi-enzyme complex analogous to: a. pyruvate kinase. b. glyceraldehyde-3-phosphate dehydrogenase. c. isocitrate dehydrogenase. d. pyruvate dehydrogenase. e. lactate dehydrogenase.

d. pyruvate dehydrogenase.

32. Which of the following represents a reaction that could be used to refill the CAC?: a. OAA → PEP b. citrate → OAA + acetyl-CoA c. Asp → α-ketoglutarate d. pyruvate → OAA e. none of the above

d. pyruvate → OAA

19. In the case of shared anabolic and catabolic pathways, the ____ serve as the points of regulation. a. largest enzymes b. ATP producing enzymes c. NADH utilizing enzymes d. rate-limiting enzymes e. all are true

d. rate-limiting enzymes

4. To position a gene in an expression vector downstream from a promoter (i.e., perform directional cloning), it is best to: a. use the largest plasmid available. b. treat the gene with DNase I. c. restrict both the gene and the plasmid with one restriction endonuclease and then screen all colonies for those that express the gene. d. restrict each end of the DNA fragment (gene) with a different restriction endonuclease and do likewise for the plasmid. e. use a vector with two sites for the same restriction endonuclease.

d. restrict each end of the DNA fragment (gene) with a different restriction endonuclease and do likewise for the plasmid.

15. A constituent of the flavin coenzymes is a. sorbitol b. mannitol c. xylitol d. ribitol e. glycerol

d. ribitol

20. Of the following fatty acids, which would have physical and physiological properties most similar to elaidic acid, pictured below? (pic on other side) a. oleic acid (18:1Δ^9) b. lauric acid (12:0) c. linoleic acid (18:2Δ^9,12) d. stearic acid (18:0) e. arachidonic acid (20:4Δ^5,8,11,14)

d. stearic acid (18:0)

9. DNA intercalating agents include all of the following EXCEPT: a. ethidium bromide. b. actinomycin D. c. acridine orange. d. streptomycin. e. all are true.

d. streptomycin.

46. The isocitrate lyase catalyzed reaction cleaves isocitrate into: a. glyoxylate and fumarate. b. succinate and acetyl-CoA. c. malate and acetyl-CoA. d. succinate and glyoxylate. e. glyoxylate and acetyl-CoA.

d. succinate and glyoxylate.

21. The only reaction of the citric acid cycle that provides substrate-level phosphorylation is catalyzed by: a. malate dehydrogenase. b. citrate synthase. c. isocitrate dehydrogenase. d. succinyl-CoA synthetase. e. nucleotide triphosphate kinase.

d. succinyl-CoA synthetase.

18. DNA ____ is analogous to twisting or untwisting a two stranded rope so that it is torsionally stressed. a. buoyant density b. hairpin turn c. cloverleaf d. supercoiling e. all of the above

d. supercoiling

33. Multiple Drug Resistant (MDR)-ATPase is a ____ repeat protein that uses ATP hydrolysis to actively transport a wide variety of drugs ____ the cell. a. multiple; into b. multiple; out of c. tandem; into d. tandem; out of e. triple; into

d. tandem; out of

48. Which of the following coenzymes is NOT used by pyruvate dehydrogenase? a. NAD+ b. FAD c. thiamine pyrophosphate d. tetrahydrofolate e. lipoic acid

d. tetrahydrofolate

7. Of the following, which would contain the largest amount of fatty acids with trans double bonds? a. the fatty acid on carbon #1 of the glycerol of phosphatidylcholine b. butter c. canola oil d. the 2 lb, 99 cent package of cookies containing partially hydrogenated cottonseed and/or soybean oil that you consumed with 3 (or more) cups of coffee while studying last night (or early this morning) e. none of the above would have very much trans-double bond containing fatty acids

d. the 2 lb, 99 cent package of cookies containing partially hydrogenated cottonseed and/or soybean oil that you consumed with 3 (or more) cups of coffee while studying last night (or early this morning)

31. The dimethoxytrityl (DMTr) group protects which functional group during synthetic DNA synthesis? a. the primary amine group of adenine and guanine b. the primary amine group of cytosine c. the 3' hydroxyl of the deoxyribose d. the 5' hydroxyl of the deoxyribose e. both A and B are correct

d. the 5' hydroxyl of the deoxyribose

11. β-D-glucopyranose in the chair form is the most widely occurring form of glucose in nature and it has the following characteristics EXCEPT: a. forms a six-membered ring. b. carbon 6 is above the plane of the chair. c. all of the −OH groups are equatorial. d. the anomeric carbon has a hydroxyl that is below the plane of the chair. e. all axial positions are occupied by −H.

d. the anomeric carbon has a hydroxyl that is below the plane of the chair

4. All are important functional groups participating in H-bond formation EXCEPT: a. amino group of the cytosine, adenine, and guanine. b. the ring nitrogens at position 3 of pyrimidines and 1 of purines. c. the electronegative oxygen atoms. d. the electron density in the double bonds of the bases. e. the carbonyl group at position 4 of uracil and thymine, position 2 of cytosine, and position 6 of guanine.

d. the electron density in the double bonds of the bases.

31. Cooked starch is more digestible because: a. it has been partially hydrolyzed during cooking. b. the amylopectin is converted to amylose during cooking. c. the enzymes that hydrolyze the starch are only active when the starch is hot. d. the starch granules take up water, swell and are more accessible to the enzymes. e. all are true.

d. the starch granules take up water, swell and are more accessible to the enzymes.

23. Active transport is uniquely characterized by: a. transport of hydrophobic molecules. b. transport of hydrophilic molecules. c. transport of a molecule or ion across a membrane, with the species going from a greater concentration to a lesser concentration. d. the tight coupling of an input of energy to drive a thermodynamically unfavorable reaction. e. absolute requirement for ATP hydrolysis, and light energy or ion gradient energy will not work.

d. the tight coupling of an input of energy to drive a thermodynamically unfavorable reaction.

20. In passive diffusion, the transported species moves across the membrane in the ____ favored direction ____. a. kinetically; using a transport protein b. kinetically; without a specific transport system/molecule c. thermodynamically; using a transport protein d. thermodynamically; without a specific transport system/molecule e. none of the above.

d. thermodynamically; without a specific transport system/molecule

24. Dehydrogenases are enzymes that: a. move hydrogens within the molecule. b. add hydrogens across double bonds. c. transfer hydrogens between substrates. d. transfer hydride ions to NAD+ (or NADP+) and release a proton. e. all are true.

d. transfer hydride ions to NAD+ (or NADP+) and release a proton.

19. Hybrid proteins or fusion proteins are produced by: a. incubation of two proteins with a protease. b. expression of genes coding for multiple proteins. c. translation of mRNAs without removing exons. d. translation of recombinant sequences from expression vectors carrying cDNA inserts cloned directly into the coding sequence of a vector-born protein-coding gene. e. all of the above.

d. translation of recombinant sequences from expression vectors carrying cDNA inserts cloned directly into the coding sequence of a vector-born protein-coding gene.

32. The enzymes α-amylase and β-amylase can cleave the ____ bonds of amylopectin but not the ____ bonds. a. α (1→6)-; α (1→4)- b. β (1→6)-; β (1→4)- c. α (1→4)-; β (1→4)- d. α (1→4)-; α (1→6)- e. α (1→6)-; β (1→4)-

d. α (1→4)-; α (1→6)-

36. Pore-forming toxins solve the problem of a need to provide hydrogen-bonding partners for the polypeptide background N−H and C=O groups in the bilayer that lacks hydrogen-bond donors and acceptors by utilizing extensive: a. salt bridge formation. b. disulfide bond formation. c. β-turns. d. α-helices and β-sheets. e. none of the above.

d. α-helices and β-sheets.

7. Nucleotides have a nitrogenous base linked to a sugar by a: a. α-anhydride bond. b. β-ester bond. c. α-N-amide bond. d. β-N-acetal (glycosidic) bond. e. α-N-hemiacetal bond.

d. β-N-acetal (glycosidic) bond.

9. The net charge on nucleotide monophosphates is: a. +1 b. 0 c. −1 d. −2 e. −3

d. −2

53. Cholecalciferol is hydroxylated twice to form ____ that acts like a ____ to regulate ____ and ____ metabolism. a. 24,25-hydroxyvitamin D; vitamin D-binding protein; calcium; chloride b. ergosterol; vitamin D-binding protein; sodium; calcium c. 7-dehydrocholesterol; hormone; calcium; phosphate d. 1,25-dihydroxycolecarciferol; prehormone; sodium; phosphate e. 1,25-dihydroxycolecarciferol; hormone; calcium; phosphate

e. 1,25-dihydroxycolecarciferol; hormone; calcium; phosphate

3. If carbon 1 is the carbonyl group of an aldohexose, which carbon determines if the sugar is a D- or L- stereoisomer? a. 1 b. 2 c. 3 d. 4 e. 5

e. 5

8. When we say that biological membranes are asymmetric structures we mean that: a. The lipids are not evenly distributed transversely in the membrane. b. The proteins are not evenly distributed over the surface of the membrane. c. Patches of cholesterol and other lipids occur on the surface of the membrane. d. Certain membrane proteins seem to prefer association with specific lipids. e. All are true

e. All are true

11. All are characteristic of YACs (yeast artificial chromosomes) EXCEPT: a. YACs can successfully propagate DNA molecules of 2 megabase pairs in length. b. YACs have been transferred into animals. c. YACs must include a centromere. d. YACs must include telomers. e. All are true.

e. All are true.

21. All are characteristics of DNA gyrase in E.coli EXCEPT: a. It hydrolyzes ATP during its reaction mechanism. b. It cuts both strands of a dsDNA. c. It works to induce negative supercoiling in DNA. d. It is classified as a topoisomerase. e. All are true.

e. All are true.

26. All are secondary structure components of tRNA EXCEPT: a. acceptor stem. b. D loop. c. Anticodon loop. d. TΨC loop. e. All are true.

e. All are true.

31. All are necessary for restriction endonuclease mapping of DNA molecules EXCEPT: a. Determining the 5;- and/or 3'-ends of the molecule. b. Electrophoresis of fragments. c. Hydrolysis with two or more endonucleases. d. Knowing where each endonuclease hydrolyzes. e. All are true.

e. All are true.

35. All are true statements about dextrans EXCEPT: a. They are used in research laboratories as a support for column chromatography (Sephadex or BioGel). b. They are repeating units of isomaltose. c. The branches may be 1→2, 1→3 or 1→4 in various species. d. They are an important component of dental plaque. e. All are true.

e. All are true.

14. Generally, over 90% of all membrane phosphatidyl serine (PS) is found on the inner monolayer of the cell membrane. Which of the following explains this phenomenon? a. when PS is found in the outer monolayer, a floppase enzyme is used to move it to the inner monolayer b. the movement of phospholipids from one monolayer to another is a very slow reaction despite the fact that it works with the concentration gradient c. under normal conditions within the cell, the activity of scramblase enzymes is relatively low and thus does not allow for movement between monolayers d. All of the above are correct e. B and C above are correct

e. B and C above are correct

16. The two step reaction catalyzed by isocitrate dehydrogenase involves: A. β-decarboxylation expelling the α-keto carboxyl as CO2. B. oxidation of the C-2 alcohol of isocitrate to form oxalosuccinate. C. oxidation of the C-2 alcohol to form oxaloacetate. D. β-elimination expelling the central carboxyl group as CO2. a. A and B b. B and C c. C and D d. A and C e. B and D

e. B and D

28. Muscle Ca2+-ATPase resembles Na+, K+-ATPase in many ways EXCEPT: a. Both have α-subunits of similar size. b. Both form covalent E-P intermediates during ATP hydrolysis. c. Both have similar mechanisms of ATP hydrolysis. d. Both have similar ion transport mechanisms. e. Both have residence on the sarcoplasmic reticulum.

e. Both have residence on the sarcoplasmic reticulum.

13. The correct sequence for colony hybridization experiments is: A. A replica of the bacterial colonies is obtained on an absorbent disc. B. Autoradiography of the disc reveals probe complementary DNA. C. Host bacteria with plasmid are plated and allowed to grow overnight. D. The disc is treated with alkali. E. The disc is reacted with labeled probe. a. A, C, E, B, D b. C, A, E, D, B c. C, E, A, B, D d. C, A, E, B, D e. C, A, D, E, B

e. C, A, D, E, B

40. All are coenzymes with an adenine nucleotide portion EXCEPT: a. ATP. b. NADH. c. Coenzyme A. d. FADH2. e. FMNH2.

e. FMNH2.

12. All of the statements about the following pairs of sugars are correct EXCEPT: a. Galactose and mannose are diastereomers. b. L-galactose and D-galactose are enatiomers. c. Glyceraldehyde and dihydroxyacetone are stereoisomers. d. Glucose and mannose are epimers. e. Glucose has fewer chiral centers than fructose.

e. Glucose has fewer chiral centers than fructose

33. ____ is an enzyme found in liver and muscle tissue used to catalyze the phosphorolysis of glycogen to ____. a. β (1→6)-Glucosidase; glucose-1-phosphate b. α-Amylase; glucose-1-phosphate c. β-Amylase; glucose d. Glycogen maltase; maltose e. Glycogen phosphorylase; glucose-1-phosphate

e. Glycogen phosphorylase; glucose-1-phosphate

36. Which of the following statements about cellulose fiber is true? a. It is a linear polymer of β (1→4) glycosidic linked glucose and galactose residues. b. It is extremely susceptible to hydrolysis. c. It is water-soluble. d. It is made up of very weak microfibrils. e. Intermolecular hydrogen bonds play a major role in stabilization of the microfibrils.

e. Intermolecular hydrogen bonds play a major role in stabilization of the microfibrils.

14. In the Southern hybridization procedure, the gel after electrophoresis is treated with NaOH and then neutralized before blotting. What is the primary function of the alkaline treatment? a. It neutralizes any acid soluble impurities in the gel. b. It cleaves the DNA into smaller fragments to permit greater efficiency of transfer. c. It inactivates any restriction endonucleases that may be in the gel. d. It neutralizes any acidic phosphate groups that might prevent hybridization. e. It denatures the duplex DNA to single-stranded DNA (ssDNA).

e. It denatures the duplex DNA to single-stranded DNA (ssDNA).

45. What causes pyridoxal-5-phosphate (PLP) to be so versatile? a. It reacts very quickly with simple sugars. b. Its ability to be a one or two electron carrier. c. The formation of a thioester bond. d. Its ability to transfer methyl groups. e. Its ability to form a Schiff base and act as an electron sink.

e. Its ability to form a Schiff base and act as an electron sink.

39. The dehydrogenase enzymes facilitate the direct transfer of hydride anion. Which of the following coenzymes is required for this transfer? a. biotin b. folic acid c. lipoic acid d. TPP e. NAD+

e. NAD+

12. All of the following are examples of nucleotide functions EXCEPT: a. CTP in phospholipid synthesis. b. UTP in complex carbohydrate synthesis. c. ATP in energy for the cell. d. GTP in protein synthesis. e. TTP in phosphoryl group transfers.

e. TTP in phosphoryl group transfers.

30. Which of the following statements correctly identifies a type II restriction endonuclease? a. They work on both DNA and RNA. b. They recognize a palindromic sequence and cut just before the palindromic sequence. c. The result of this endonuclease is blunt ends. d. They degrade DNA by subsequently removing bases from each end. e. They cut DNA only at sites in specific nucleotide sequences with a two-fold axis of symmetry.

e. They cut DNA only at sites in specific nucleotide sequences with a two-fold axis of symmetry.

3. ____ is the most oxidized state for a purine derivative and is ____ found in nucleic acids. a. Guanine; always b. Adenine; always c. Hypoxanthine; never d. Xanthine; always e. Uric acid; never

e. Uric acid; never

13. Metabolon characteristics include all EXCEPT: a. "units of metabolism". b. discrete multienzyme complex. c. soluble enzymes associated into stable multienzyme complexes. d. membrane bound multienzyme systems. e. all are characteristics.

e. all are characteristics.

1. Carbohydrate characteristic chemical features include all EXCEPT: a. the potential to form multiple hydrogen bonds. b. the existence of one or more asymmetric centers. c. the capacity to form polymeric structures. d. the ability to exist in either linear or ring structures. e. all are true.

e. all are true

28. Fumarase catalyzes a reaction for which each of the following is true EXCEPT: a. fumarate is hydrated b. the reaction is stereospecific for a trans product c. the reaction involved is similar to that carried out by aconitase d. L-malate is the produced e. all are true

e. all are true

1. The plasma membrane is responsible for all EXCEPT: a. energy transduction. b. exclusion of certain toxic ions and molecules. c. signal transduction. d. accumulation of cell nutrients. e. all are true.

e. all are true.

11. All are characteristics of anabolism EXCEPT: a. assembly of complex molecules. b. formation of new covalent bonds. c. ATP provides energy. d. NADPH is an electron donor. e. all are true.

e. all are true.

13. All are true for aconitase EXCEPT: a. iron atom acts as a Lewis acid. b. equilibrium favors citrate. c. contains an iron-sulfur cluster. d. one Fe3+ coordinates with C-3 carbonyl and hydroxyl group of citrate. e. all are true.

e. all are true.

16. Nucleic acid hybridization is a commonly employed procedure in molecular biology to investigate all EXCEPT: a. evolutionary relationships. b. specific genes against a vast background. c. specific probe based isolation of genes. d. quantify gene expression. e. all are true.

e. all are true.

2. Fatty acids are all EXCEPT: a. either saturated or unsaturated. b. found seldom in free form. c. mostly found with an even number of carbons. d. found in linear, branched and cyclic forms. e. all are true.

e. all are true.

23. All are properties of nucleosomes EXCEPT: a. protein spools neatly wrapped with DNA. b. fundamental structural unit in chromatin. c. protein spools made up of pairs of histones H2A, H2B, H3 and H4 octameric aggregates. d. DNA binds histones by ionic bonds of positively charged amino acids and the negative charged phosphate groups. e. all are true.

e. all are true.

29. All are strategies for human gene therapy EXCEPT: a. use of expression cassettes. b. incorporation into expression vectors. c. transfer into patient cells. d. introduction of transformed stem cells. e. all are true.

e. all are true.

30. The Ca2+-ATPase structure is like many of the other active transport proteins in that it has all of the components EXCEPT: a. transmembrane domain of ten α-helical segments. b. a large cytoplasmic domain with nucleotide binding domain. c. a phosphorylation domain. d. an actuator domain. e. all are true.

e. all are true.

38. All are principal allosteric regulatory "signals" controlling the TCA cycle activity EXCEPT: a. acetyl-CoA. b. NADH. c. NAD+. d. ATP. e. all are true.

e. all are true.

5. Liposomes are all EXCEPT: a. used to introduce contrast agents into the body for diagnostic imaging procedures. b. able to fuse with cells. c. highly stable structures. d. possible to prepare with different inside and outside solutions. e. all are true.

e. all are true.

35. Excess carbohydrate and fat in the human diet is stored as triacylglycerols. The risk of which of the following would be increased in an individual who consistently consumes too much fat and carbohydrate? a. atherosclerosis b. heart disease c. colon cancer d. breast cancer e. all of the above

e. all of the above

22. All are characteristics of succinyl-CoA synthetase EXCEPT: a. succinyl-CoA can be used to drive phosphorylation of GDP or ADP. b. the enzyme is named for the reverse reaction. c. it provides an example of substrate-level phosphorylation. d. succinyl-phosphate is an intermediate in the reaction catalyzed by succinyl-CoA synthetase. e. all of the above are true.

e. all of the above are true.

43. Pyridoxal-5-phosphate (PLP) is involved in all EXCEPT: a. aminotransferases (transaminases). b. α- and β-decarboxylations. c. β- and γ-eliminations. d. racemizations. e. all of the above.

e. all of the above.

20. The coenzymes listed below are associated with α-ketoglutarate dehydrogenase complex EXCEPT: a. [FAD]. b. TPP. c. lipoamide. d. NAD+. e. biotin.

e. biotin.

30. The original development of PCR did not use the Taq polymerase. What is the reason that the Taq polymerase is currently used? a. the DNA melting step at 95°C would cause denaturation of most DNA polymerases from other organisms b. the Taq polymerase is one of the most rapid DNA polymerase enzymes known and is therefore extremely useful for PCR c. the original method of PCR required that DNA polymerase be added prior to each round of elongation, something that is not conducive to automation d. the Taq polymerase is the only DNA polymerase that will allow production of 2n amounts of DNA (where n=number of cycles) e. both A and C are correct

e. both A and C are correct

6. Which of the following properties describe both purines and pyrimidines? a. they are aromatic b. they are composed of 6-membered rings c. they exhibit strong absorption of UV light d. they always contain a carbonyl group e. both A and C are correct

e. both A and C are correct

60. The conversion of glucose-6-phosphate to glucose-1-phosphate has a ΔG ́° of + 8.4 kJ/mol. How can a reaction such as this proceed in a cell? a. it must be coupled to ATP hydrolysis b. the product must be rapidly used in a subsequent step of the pathway c. it can only occur with the help of an enzyme d. this reaction can not proceed and must go in the reverse manner e. both B and C are correct

e. both B and C are correct

15. B-DNA is characterized by which of the following? a. 12 base pairs per helix turn b. helix axis runs through the minor groove c. a wide major groove an narrow minor groove d. right-handed helix e. both C and D are correct

e. both C and D are correct

27. The major interactions that fold components of the secondary structure of tRNA together and bend the cloverleaf into a stable L-shaped tertiary form are: a. hydrophobic interactions. b. base-pairing interactions. c. ionic interactions. d. electrostatic interactions. e. both a and b.

e. both a and b.

9. The advantages of using the pET plasmid system include ____. a. genes to be expressed are under the control of a T7 promoter b. the T7 polymerase is slower than a typical E coli polymerase c. the expressed protein never accounts for more than 5% of the total cell protein d. the T7 polymerase is under the control of the lac operon and is thus only active when induced by an agent such as IPTG e. both a and d are correct

e. both a and d are correct

19. Which of the following is true regarding membrane function? a. a caveola contains a very high concentration of cholesterol and unsaturated phospholipids b. scaffolding proteins, particularly those containing BAR domains, result in curvature of the cell membrane c. lateral membrane diffusion within a biological membrane is a completely unrestricted process d. membrane fusion with vesicles is often accomplished with the aid of a SNARE protein e. both b and d are correct

e. both b and d are correct

32. When an individual has a ____ nitrogen balance, excess dietary protein is converted into ____. a. negative; energy b. positive; energy c. negative; nucleic acids d. positive; protein for storage e. both b and d are true

e. both b and d are true

19. All of the following are terpenes EXCEPT: a. squalene. b. α-tocopherol (vitamin E). c. coenzyme Q (UQ). d. limonene. e. cetyl palmitate (spermaceti).

e. cetyl palmitate (spermaceti).

16. In a double-stranded nucleic acid, guanine typically base-pairs with: a. adenosine. b. uracil. c. inosine. d. thymine. e. cytosine.

e. cytosine.

13. Individuals with uncontrolled diabetes mellitus may have ____ levels of blood ____ so they test their blood for ____. a. elevated; fructose; gluconic acid b. depressed; glucose; oxidizing sugars c. elevated; glucose; fructose d. depressed; gluconic acid; reducing sugars e. elevated; glucose; reducing sugars

e. elevated; glucose; reducing sugars

44. Thioesters have higher ____ than that of oxygen esters. a. mobility b. electronegativity c. resonance d. positive ΔG e. group transfer potential

e. group transfer potential

47. The core protein of a proteoglycan is noncovalently attached to: a. oligosaccharides. b. glycosaminoglycans. c. keratin sulfate. d. an outer protein. e. hyaluronic acid backbone.

e. hyaluronic acid backbone.

48. Cartilage-matrix proteoglycan has all of the following properties EXCEPT: a. responsible for the flexibility and resiliency of cartilage. b. has a hyaluronic acid binding domain. c. has reversible hydration-dehydration properties. d. contains both N-linked and O-linked oligosaccharides. e. is an integral transmembrane protein.

e. is an integral transmembrane protein.

52. Retinol and the carotenoids follow the pathways of ____ digestion and absorption. a. complex carbohydrates b. proteins c. simple sugars d. nucleic acids e. lipids

e. lipids

24. Histones are rich in the amino acids ____, and interact with DNA via ____. a. alanine and glycine; covalent bonds b. glutamic acid and aspartic acid; hydrogen bonds c. glutamic acid and aspartic acid; ionic bonds d. lysine and arginine; hydrogen bonds e. lysine and arginine; ionic bonds

e. lysine and arginine; ionic bonds

11. Flippases are enzymes that flip: a. fatty acids from one position on glycerol to another position. b. glucose from α- to β-glucose. c. amino acids from one position to another in a protein. d. cholesterol from one organelle to another. e. phospholipids across to the other side of a membrane.

e. phospholipids across to the other side of a membrane.

26. PCR-based mutagenesis is used to create: a. mutant strains of an eukaryotic organism. b. generally modified plasmid vectors. c. mutant bacterial strains. d. mutant DNA libraries. e. specifically altered proteins.

e. specifically altered proteins.

31. In a DNA microarray, how many different oligonucleotides can be produced if each oligonucleotide is 20 nucleotides long? a. 4^20 b. 20^4 c. 80 d. 20 e. none of the above

a. 4^20

51. Which vitamin is essential to vision? a. A b. C c. D2 d. B12 e. B1

a. A

23. The correct sequence of steps between succinyl-CoA and ATP in mammals to "preserve" the energy of the thioester bond are: A. succinyl-phosphate. B. phosphohistidine. C. GTP. D. Acetyl-CoA. a. A, B, C b. B, C, A c. A, C, D d. C, B, A e. D, A, B

a. A, B, C

8. Double helical DNA:RNA hybrids and double-stranded regions of RNA chains often assume an: a. A-like conformation. b. B-like conformation. c. Z-like conformation. d. all of the above. e. none of the above.

a. A-like conformation.

18. Isocitrate dehydrogenase has all of the characteristics EXCEPT: a. ADP raises the Km for isocitrate by a factor of 10. b. virtually inactive in the absence of ADP. c. sufficiently exergonic to pull the aconitase reaction forward. d. allosterically inhibited by NADH and ATP. e. an oxidative-decarboxylation reaction.

a. ADP raises the Km for isocitrate by a factor of 10.

17. Allosteric inhibitors of isocitrate dehydrogenase include ____ and ____, whereas ____ acts as an allosteric activator,____ the Km for isocitrate. a. ATP; NADH; ADP; lowering b. ATP; ADP; AMP; lowering c. NADH; NADPH; AMP; increasing d. NADH; ATP; ADP; increasing e. NADH; ATP; AMP; lowering

a. ATP; NADH; ADP; lowering

40. Cellulose and chitin are similar in all of the following ways EXCEPT: a. Both are polymers of glucose. b. Both are structural polysaccharides. c. Both have extended ribbon conformations. d. Both have extensive hydrogen bonding. e. All are true.

a. Both are polymers of glucose.

7. All are correct statements about the reaction catalyzed by citrate synthase EXCEPT: a. Citrate synthase is allosterically activated by ATP. b. The complete chemical equation is: Oxaloacetate + acetyl-CoA + H2O → citrate + CoA c. Citryl-CoA is formed as an intermediate. d. The mechanism involves attack of the carbanion of acetyl-CoA on the carbonyl carbon of oxaloacetate. e. The enzyme uses general base catalysis to generate the reactive species.

a. Citrate synthase is allosterically activated by ATP.

3. How is a fluorescent tag that is unique for each nucleotide incorporated into the newly synthesized DNA using the chain termination protocol for DNA sequencing? a. Each of the ddNTPs is labeled with a specific fluorophore b. The primer strand is labeled with a specific fluorophore c. The template strand is labeled prior to the experiment with complimentary fluorophores d. The 5'-end is labeled with a fluorophore. e. All dNTPs are labeled with a fluorophore

a. Each of the ddNTPs is labeled with a specific fluorophore

31. All are characteristic of the gastric proton pump EXCEPT: a. Gastric proton pump requires high levels of dietary K+ to create a K+ gradient. b. Gastric proton pump is a H+, K+-ATPase. c. Gastric proton pump maintains a pH gradient of about 6.6 across the mucosal cell membrane. d. Gastric proton pump is electroneutral. e. Gastric proton pump produces a net influx of HCl into the stomach.

a. Gastric proton pump requires high levels of dietary K+ to create a K+ gradient.

30. Which of the following histone proteins has only one copy per nucleosome? a. H1 b. H2A c. H2B d. H3 e. H4

a. H1

10. As a result of mutarotation, D-glucose exists in all of the following forms EXCEPT: a. L-glucopyranose. b. β-anomer. c. free aldehyde. d. α-anomer. e. all are true.

a. L-glucopyranose

37. Secondary active transport across a membrane refers to a. Movement of a molecule across a membrane and against its concentration gradient powered by an ion gradient that is created by a different transporter b. Movement of a molecule across a membrane and against its concentration gradient through a transporter that is directly powered by ATP hydrolysis c. Movement of a molecule across a membrane powered by its own concentration gradient d. Movement of a molecule across a membrane through a transporter that has an alpha-helical secondarystructure. e. none of the above

a. Movement of a molecule across a membrane and against its concentration gradient powered by an ion gradient that is created by a different transporter

35. The System A for alanine transport into liver is a(n) ____ system that can be activated by ____ and ____. a. Na+-symport; substrate (alanine); hormones b. K+-symport; substrate (alanine); hormones c. H+-antiport; pH change; alanine d. ATP-antiport; alanine; pH change e. None are true

a. Na+-symport; substrate (alanine); hormones

7. What is the relationship between photoautotrophs and heterotrophic cells? a. Photoautotrophs use light energy for synthesis of organic molecules while heterotrophs metabolize organic substances for fuel and building blocks. b. photoautotrophs use organic compounds as a source of carbon while heterotrophs use CO2 as a source of carbon. c. Photoautotrophs synthesize CO2 while heterotrophs synthesize O2. d. Heterotrophs convert solar energy into chemical energy while photoautotrophs break down organic molecules. e. There is no relationship between the two.

a. Photoautotrophs use light energy for synthesis of organic molecules while heterotrophs metabolize organic substances for fuel and building blocks.

29. All are true for enzymes that cleave nucleic acids EXCEPT: a. They are of the lyase class of enzymes. b. They are called nucleases. c. They belong to the sub-class of phosphodiesterases. d. They are found in all cells for "house keeping", and secreted by the pancreas for digestion. e. They are found in fungi and snake venoms

a. They are of the lyase class of enzymes.

58. What coenzyme is found in pyruvate decarboxylase that aids in the decarboxylation of α-keto acids? a. Thiamine pyrophosphate b. Folic acid c. Biotin d. Lipoic acid e. none of the above

a. Thiamine pyrophosphate

43. All of the following are inhibitors of citrate synthase EXCEPT: a. acetyl-CoA b. NADH c. succinyl-CoA d. ATP e. all are inhibitors

a. acetyl-CoA

42. Glycosaminoglycans are unbranched polysaccharides consisting of alternating residues of uronic acid and hexosamine. Which of the following is NOT a glycosaminoglycan? a. agaropectin b. heparin c. dermatan sulfate d. hyaluronate e. chondroitin-4-sulfate

a. agaropectin

8. Body fat is a major storage form of energy because it: a. aggregates in a highly anhydrous form (without additional water weight). b. yields about 17 kJ/g (4 cal/g) of energy. c. has low insulation properties. d. is highly hydrated and easy to metabolize. e. yields about 25 kJ/g (6 cal/g) of energy.

a. aggregates in a highly anhydrous form (without additional water weight).

10. Glycerolphospholipids are all EXCEPT: a. also called sphingolipids. b. essential components of cell membranes. c. made up of 1,2-diacylglycerol and a phosphate group. d. members of the phospholipids. e. all are true.

a. also called sphingolipids.

46. Which of the following represents an example of a proteoglycan? a. attachment of several molecules of heparin to the peptide antithrombin III b. attachment of a Gal-β(1,3)-GalNAc disaccharide to the fish antifreeze protein c. attachment of a small oligosaccharide to an immunoglobulin d. attachment of a small antigenic determinant to a membrane bound protein of a cell e. none of the above

a. attachment of several molecules of heparin to the peptide antithrombin III

8. Nucleosides are relatively stable to ____ hydrolysis, and pyrimidine nucleotides are stable to____ hydrolysis, but purine nucleotides are unstable to ____ hydrolysis. a. base; acid; acid b. base; base; acid c. acid; base; base d. acid; acid; base e. none are true

a. base; acid; acid

23. Prokaryotic chromosomes are typically ____, while eukaryotic chromosomes are ____ a. circular; linear and richly protein-associated b. circular and richly protein-associated; linear c. linear and richly protein-associated; circular d. linear; circular and richly protein-associated e. none are true.

a. circular; linear and richly protein-associated

9. Citrate synthase is a ____ with binding of ____ inducing a conformational change ____ the binding of acetyl-CoA, and____ is an allosteric inhibitor. a. dimer; OAA; increasing; NADH b. dimer; OAA; decreasing; NADH c. tetramer; OAA; decreasing; NAD+ d. monomer; pyruvate; decreasing; ATP e. monomer; pyruvate; increasing; ATP

a. dimer; OAA; increasing; NADH

24. Secondary active transport is: a. establishment of a cation or anion gradient with an ATPase that subsequently drives transport of an amino acid or sugar against a concentration gradient. b. the use of an ATPase to establish an anion or cation gradient. c. the antiport process of transporting species in opposite directions. d. establishment of an ATP gradient across a membrane that drives uptake of sugars. e. symport of malate and glutamate so that metabolism can synthesize ATP.

a. establishment of a cation or anion gradient with an ATPase that subsequently drives transport of an amino acid or sugar against a concentration gradient.

2. All are features of a plasmid useful for cloning EXCEPT: a. expressed sequence tag. b. a cloning site. c. a replicator (origin of replication). d. a selectable marker. e. all are features.

a. expressed sequence tag.

18. To express a eukaryotic protein in E. coli, the eukaryotic cDNA must be cloned in a(n) ____ that contains ____ and____. a. expression vector; promoter; ribosomal-binding site b. hybridization complex; promoter; transition start site c. mRNA; ribosomal-binding site; promoter d. mRNA; introns; exons e. none of the above

a. expression vector; promoter; ribosomal-binding site

21. Glucose transport across cell membranes varies depending upon blood glucose levels. When glucose levels are high, glucose transport exhibits saturation kinetics. When glucose concentrations are low, the transport of glucose across the membrane is dependent upon the sodium ion concentration. What types of transport is observed for glucose? a. facilitated diffusion at high [glucose], secondary active transport at low [glucose] b. simple diffusion at high [glucose], secondary active transport at low [glucose] c. facilitated diffusion at high [glucose], primary active transport at low [glucose] d. simple diffusion at high [glucose], primary active transport at low [glucose] e. none of the above are correct

a. facilitated diffusion at high [glucose], secondary active transport at low [glucose]

41. In mammalian tissues, isocitrate dehydrogenase is allosterically stimulated by: a. high NAD+/NADH and high ADP/ATP ratios. b. low ADP/ATP and low NAD+/NADH ratios. c. high NAD+/NADH and low ADP/ATP ratios. d. low NAD+/NADH and high ADP/ATP ratios. e. none of the above.

a. high NAD+/NADH and high ADP/ATP ratios.

20. Reporter genes such as those for green fluorescent protein (GFP) are found on many commercial plasmids. These genes are useful to determine: a. if the plasmid is in the host. b. if a gene is present in a library. c. if a foreign protein is being expressed on a vector. d. the relative strength of a promoter sequence. e. all of the above.

a. if the plasmid is in the host.

7. Which of the following would be the most likely interaction between a peripheral membrane protein that contained a high lysine content and a membrane? a. ionic interaction b. hydrophobic interaction c. hydrogen bonding d. covalent bonding e. both a and c

a. ionic interaction

44. An essential feature of the glyoxylate cycle, which is not associated with the TCA cycle is: a. it utilizes condensation of acetyl-CoA with glyoxylate b. each complete cycle produces a net gain of two 4-carbon molecules c. it occurs in chloroplasts and the mitochondria of plant seeds d. mammals use the glyoxylate cycle for gluconeogenesis e. it is a reductive pathway that utilizes NADPH as an electron source

a. it utilizes condensation of acetyl-CoA with glyoxylate

23. All of the following are homodisaccharides EXCEPT: a. lactose. b. maltose. c. isomaltose. d. cellobiose. e. all are homodisaccharides.

a. lactose

1. A fatty acid with eighteen carbons and one double bond could be designated all EXCEPT: a. linoleic acid. b. 18:1. c. cis-9-octadecenoic acid. d. oleic acid. e. elaidic acid

a. linoleic acid.

2. Most organisms show ____ in their major pathways of metabolism. a. marked similarity b. some similarity c. minimal similarity d. considerable diversity e. major diversity

a. marked similarity

57. The statements are correct about the diseases caused by vitamin deficiencies EXCEPT: a. niacin deficiency leads to gout. b. vitamin A deficiency leads to night blindness that can be reversed by adding β-carotene to the diet. c. vitamin B12 prevents pernicious anemia. d. vitamin D deficiency leads to demineralization of bones and rickets. e. vitamin C prevents scurvy.

a. niacin deficiency leads to gout.

5. Photoheterotrophs require: a. organic carbon sources and light. b. carbon dioxide and light. c. organic carbon sources and oxidation-reduction reactions. d. carbon dioxide and inorganic compounds. e. carbon dioxide and oxidation-reduction reactions.

a. organic carbon sources and light.

32. H+-transporting ATPases found in ____ break down bone during normal bone remodeling are of the ____ type of ATPases. a. osteoclasts; vacuolar (V-) b. osteoclast; H+, K+-ATPase c. osteoblast; H+, K+-ATPase d. osteoblast; vacuolar (V-) e. osteoclast; Na+, K+-ATPase

a. osteoclasts; vacuolar (V-)

55. Unsaturated fatty acids in membranes are particularly susceptible to ____ and vitamin E may provide protection because it is a potent ____. a. oxidation; antioxidant b. reduction; reducing agent c. reduction; reducing agent d. substitution; reactant e. substitution; reactant

a. oxidation; antioxidant

10. Solar energy is converted to the chemical energy of organic molecules by ____, and ____ recover this energy by metabolizing the organic substrates. a. photoautotrophs; heterotrophs b. heterotrophs; chemoautotrophs c. chemoautotrophs; heterotrophs d. photoautotrophs; chemoautotrophs e. none are true.

a. photoautotrophs; heterotrophs

29. In prokaryotic cells, phospholipid synthesis and oxidative phosphorylation are carried out in: a. plasma membranes. b. cytosol. c. mitochondria. d. ribosomes. e. endoplasmic reticulum.

a. plasma membranes.

6. If DNA fragments of about 4 kb are to be cloned, which vector would be most useful? a. plasmid b. cosmid c. YACs (yeast artificial chromosomes) d. bacteriophage lambda e. E. coli chromosome

a. plasmid

26. A possible function of NADPH is to: a. provide reducing equivalents to synthesize glucose from CO2. b. carry electrons from anabolic reactions. c. provide a source of hydrogens for oxidative biosynthesis. d. be reduced by hydride ions to form NAD+. e. produce an oxidative product.

a. provide reducing equivalents to synthesize glucose from CO2.

2. Which is a six-membered heterocyclic aromatic ring? a. pyrimidine b. purine c. anose d. sugar portion of DNA e. ribonucleotide

a. pyrimidine

49. Which of the following is correctly paired with its inhibitor? a. pyruvate dehydrogenase: phosphorylation b. isocitrate dehydrogenase: AMP c. α-ketoglutarate dehydrogenase: NAD+ d. citrate synthase: acetyl CoA e. none of the above are correct

a. pyruvate dehydrogenase: phosphorylation

4. All are true for DNA polymerase EXCEPT: a. requires a primer with a free 5'-OH end, but the 3'-end may be phosphorylated. b. copies the sequence of nucleotides of one strand to form a new second strand. c. copies the sequence of nucleotides of one strand in a complementary fashion. d. generates dsDNA from ssDNA e. synthesizes new strands by adding successive nucleotides in the 5'→3' direction.

a. requires a primer with a free 5'-OH end, but the 3'-end may be phosphorylated.

3. Lipid bilayers differ from micelles in that micelles are: a. self limiting structures. b. formed spontaneously. c. stable in aqueous solution. d. often transformed into vesicles. e. all are true.

a. self limiting structures.

27. ____ are important in the processing of eukaryotic gene transcripts into mature messenger RNAs for export from the nucleus into cytoplasm. a. snRNAs as snRNPs b. tRNAs c. rRNAs d. siRNAs e. stRNAs

a. snRNAs as snRNPs

30. In plant cells, starch is hydrolyzed by ____ to release ____ and a starch molecule with ____. a. starch phosphorylase; glucose-1-phosphate; one less glucose unit b. salivary α-amylase; maltose 1-phosphate; two less glucose units c. starch phosphorylase; maltose 1-phosphate; two less glucose units d. α(1→6) glucosidase; glucose-6-phosphate; one less glucose unit e. starch hydrolase; glucose; one less glucose unit

a. starch phosphorylase; glucose-1-phosphate; one less glucose unit

21. Each cycle of amplification in PCR involves all of the steps EXCEPT: a. the addition of fresh dNTPs to the reaction mixture. b. annealing of oligodeoxyribonucleotide primers to DNA. c. thermal denaturation of the target duplex DNA. d. reaction with DNA polymerase at approximately 70°C. e. none of the above.

a. the addition of fresh dNTPs to the reaction mixture.

12. All are true for phase transitions of lipid bilayers EXCEPT: a. the transitions are exothermic. b. particular phospholipids display characteristic transition temperatures. c. pure phospholipid bilayers have narrow transition ranges. d. volume changes usually are associated with phase transitions. e. solutes interacting with membrane lipids affect transition temperatures.

a. the transitions are exothermic.

25. Individual amino acids are attached to their corresponding tRNAs: a. through an ester linkage to the 3'-OH in the acceptor stem. b. through an amide linkage to the anticodon loop. c. through an amide linkage to the adenine ring at the 3'end of the tRNA. d. through a phosphoester linkage to the 5' end of the tRNA. e. None of the above.

a. through an ester linkage to the 3'-OH in the acceptor stem.

33. The anaplerotic reactions associated with the TCA cycle are a result of the: a. use of many of the TCA cycle intermediates in biosynthesis. b. oxidative nature of the TCA cycle. c. decarboxylation reactions. d. production of GTP and reduced coenzymes. e. irreversible nature of some of the TCA cycle reactions.

a. use of many of the TCA cycle intermediates in biosynthesis.

27. In photosynthesis, NADPH is generated as light is used to oxidize ____ to ____. a. water; O2 b. water; CO2 c. NADPH; O2 d. water; NADP+ e. CO2; NADPH

a. water; O2

28. Which of the following bonds would be cleaved by phospholipase C? (pic on other side) a. 1 b. 2 c. 3 d. 4 e. none of the above

b. 2

39. In a typical Na+,K+-ATPase, _____ sodium ions are moved from the _____ of the cell while _____ potassium ions aremoved from the _____ of the cell a. 2; inside to outside; 3; outside to inside b. 3; inside to outside; 2; outside to inside c. 2; outside to inside; 3; inside to outside d. 3; outside to inside; 2; inside to outside e. none of the above

b. 3; inside to outside; 2; outside to inside

25. What would be the 9-residue primer used to amplify: 5'-ATCGACGTTACGCTACATAGCATAAGGCTT-3' a. 5'-TAGCTGCAA-3' b. 5'-AAGCCTTAT-3' c. 5'-UAGCUGCAA-3' d. 5'-AAGCCUUAU-3' e. 5'-TGCGATGTA-3'

b. 5'-AAGCCTTAT-3'

37. The three reactions of the citric acid cycle with large negative ΔG values include: A. citrate synthase. B. aconitase. C. isocitrate dehydrogenase. D. α-ketoglutarate dehydrogenase. E. succinyl-CoA synthetase. F. succinyl-CoA dehydrogenase. G. fumarase. H. malate dehydrogenase. a. A, B, C b. A, C, D c. C, E, F d. B, C, E e. A, C, H

b. A, C, D

43. ____ and ____ are found in tendons, cartilage and other connective tissue. a. Heparin; chondroitins b. Chondroitins; keratin sulfate c. Keratin sulfate, dermatan sulfate d. Hyaluronate, keratin sulfate e. All are true.

b. Chondroitins; keratin sulfate

41. All are true for agarose EXCEPT: a. Forms a double helix with a central core large enough to accommodate large quantities of water. b. Consists of only a linear component. c. Is a chain of alternating D-galactose and 3,6-anhydro-L-galactose, with side-chains of 6-methyl-D-galactose. d. Readily forms gels that are up to 99.9% water. e. All are true.

b. Consists of only a linear component.

14. Which of the following enzymes introduces negative supercoils into DNA? a. DNA polymerase b. DNA gyrase c. DNA ligase d. primase e. DNA photolyase

b. DNA gyrase

44. ____ are important components of the vitreous humor of the eye and of synovial fluid that lubricates the joints. a. Heparin b. Hyaluronates c. Chondroitins d. Keratin sulfates e. All are true

b. Hyaluronates

18. ____ and ____ are glycosamines linked to three-carbon acids at the C-1 or C-3 positions, and components of the polysaccharides of cell higher organisms and bacterial cell walls. a. Glucosides; galactosides b. Muramic acid; neuraminic acid c. Gluconic acid; glucuronic acid d. Sorbitol; ribitol e. None of the above

b. Muramic acid; neuraminic acid

61. For the following reaction, what coenzyme is missing from the reactants? (pic on other side) a. FADH2 b. NAD+ c. acetyl CoA d. NADH e. NADPH

b. NAD+

20. In phototrophs, ____ and ____ are the two energy-rich primary products from the transformation of light energy into chemical energy. a. ATP; NAD+ b. NADPH; ATP c. NADH; NADPH d. ATP; NADH e. ATP; NADH

b. NADPH; ATP

31. Which of the following statements regarding nutrition is FALSE? a. Dietary protein is a source of essential amino acids b. Organisms can produce all of the essential energy yielding nutrients and micronutrients needed c. Complex carbohydrates can provide simple sugars for the glycolytic pathway d. Essential fatty acids are components of biological membranes e. Fiber is needed to help clear the digestive tract

b. Organisms can produce all of the essential energy yielding nutrients and micronutrients needed

13. Platelet activating factor (PAF) has all of the characteristics EXCEPT: a. PAF is a potential mediator in inflammation, allergic responses and shock. b. PAF is a sphingolipid. c. PAF has a beneficial effect on toxic-shock syndrome. d. PAF is involved in implantation of the egg in the uterine wall. e. PAF stimulates production of fetal lung surfactant.

b. PAF is a sphingolipid.

36. The reaction CO2 + PEP + GDP <--> OAA + GTP is catalyzed by: a. PEP carboxylase. b. PEP carboxykinase. c. malic enzyme. d. pyruvate carboxylase. e. None are true.

b. PEP carboxykinase.

7. All of the following are characteristics for in vitro DNA synthesis EXCEPT: a. DNA polymerase adds nucleotides in a 5'→3' direction. b. The primer strand of DNA determines the nucleotides added. c. Correct hydrogen bonding is the primary check of the newly synthesized DNA. d. A primer strand must contain a free 3'-OH. e. DNA polymerase copies the complementary strand of DNA.

b. The primer strand of DNA determines the nucleotides added.

8. Which statement is most likely to be true concerning obligate anaerobes? a. These organisms can use oxygen if it is present in their environment. b. These organisms cannot use oxygen as their final electron acceptor. c. These organisms carry out fermentation for at least 50% of their ATP production. d. Most of these organisms are vegetative fungi. e. None of the above.

b. These organisms cannot use oxygen as their final electron acceptor.

9. Membranes with unsaturated fatty acids in their components are more flexible and fluid because: a. Unsaturated fatty acids pack closely together to form ordered arrays. b. Unsaturated fatty acids bend at the double bond preventing close packing. c. Saturated fatty acids have a "kink" that produces more fluid aggregates. d. Unsaturated fatty acids have cis double bonds that prevent formation of the "kink." e. All of the above are correct.

b. Unsaturated fatty acids bend at the double bond preventing close packing.

29. Which of the following best describes the following molecule? (pic on other side) a. a monoterpene with a tail-to-tail linkage b. a monoterpene with a head-to-tail linkage c. a diterpene with a tail-to-tail linkage d. a diterpene with a head-to-tail linkage e. none of the above

b. a monoterpene with a head-to-tail linkage

8. Glucose most commonly forms which of the following structures? a. a pyranose using the hydroxyl group on carbon 4 b. a pyranose using the hydroxyl group on carbon 5 c. a pyranose using the hydroxyl group on carbon 6 d. a furanose using the hydroxyl group on carbon 3 e. a furanose using the hydroxyl group on carbon 4

b. a pyranose using the hydroxyl group on carbon 5

11. In most cases, glycerol phosphatides have ____ fatty acid at position 1 and ____ fatty acid at position 2 of the glycerol. a. a saturated; a saturated b. a saturated; an unsaturated c. an unsaturated; a saturated d. an unsaturated; an unsaturated e. none are true.

b. a saturated; an unsaturated

27. How does RNA interference function? a. siRNA binds to genes and prevents transcription b. a single strand of the siRNA binds to the gene transcript, preventing translation c. the double stranded siRNA binds to mRNA to prevent ribosomal association d. siRNA binds to RNA polymerase preventing mRNA production e. none of the above

b. a single strand of the siRNA binds to the gene transcript, preventing translation

1. All are characteristic of plasmids EXCEPT: a. naturally occurring, circular extrachromosomal DNA. b. able to perpetuate themselves without a host organism. c. artificial plasmids can be constructed by restriction endonuclease digestion, insertion, and ligation. d. harbor genes for novel metabolic activities. e. an origin of replication must be included in the plasmid to facilitate propagation.

b. able to perpetuate themselves without a host organism.

16. Many of the catabolic pathways converge to the common two-carbon intermediate: a. alanine. b. acetyl group of acetyl-CoA. c. lactic acid. d. glucose. e. carbon dioxide.

b. acetyl group of acetyl-CoA.

14. Fluoroacetate is a potent inhibitor of the TCA cycle. Which step of the TCA cycle is inhibited as a result of fluoroacetate entering the TCA cycle? a. citrate synthase b. aconitase c. isocitrate dehydrogenase d. α-ketoglutarate dehydrogenase e. succinyl-CoA synthetase

b. aconitase

19. All of the following are important characteristics of DNA EXCEPT: a. a 1:1 ratio between pyrimidine residues and purine residues. b. adenine base pairs with uracil. c. hydrogen bonding between base pairs. d. information contained in the sequence of one strand conserved in the sequence of other strand. e. information is accessed through transcription of the information into RNA.

b. adenine base pairs with uracil.

22. In eukaryotic cells, a class of ____- and ____-rich proteins called ____ interact ionically with the anionic phosphate groups in the DNA backbone to form ____. a. lysine; leucine; prions; ribosomes b. arginine; lysine; histones; nucleosomes c. arginine; alanine; histones; nucleosomes d. arginine; lysine; prions; ribosomes e. none are true.

b. arginine; lysine; histones; nucleosomes

38. Cellulose is extremely resistant to hydrolysis, but cellulase catalyzes the hydrolysis and comes from: a. the pancreas. b. bacteria that live in the rumen. c. the liver. d. H+ secreted into the rumen. e. the intestinal wall.

b. bacteria that live in the rumen.

46. All of the coenzymes listed participate in electron transfer EXCEPT: a. FAD. b. biotin. c. NAD+. d. vitamin C. e. lipoic acid.

b. biotin.

22. Which of the following explains why the disaccharide sucrose is not a reducing sugar? a. the primary hydroxyl groups are oxidized to carboxylic acids b. both anomeric carbons are involved in formation of the glycosidic bond c. the glycosidic bond is in the α configuration d. it is composed of a furanose and a pyranose e. none of the above

b. both anomeric carbons are involved in formation of the glycosidic bond

3. Which of the following statements is true regarding metabolic pathways? a. catabolic pathways are generally reductive while anabolic pathways are generally oxidative b. catabolic pathways use a wide variety of substrates to produce a small number of waste products. c. an amphibolic pathway is extremely wasteful because it simultaneously operates as both an anabolic pathway and a catabolic pathway. d. NAD+ is used as a reducing agent in catabolic pathways while NADPH is used as an oxidizing agent in anabolic pathways e. none of the above

b. catabolic pathways use a wide variety of substrates to produce a small number of waste products.

3. If the pBR322 were treated with PstI in order to insert a gene into the plasmid, which of the following would be correct regarding cells that were transformed with the resulting vector? (pic on other side... not quite same, but close enough to original) a. cells that contained the desired vector would be resistant to ampicillin but sensitive to tetracycline b. cells that contained the desired vector would be resistant to tetracycline but sensitive to ampicillin c. cells that contained the desired vector would be resistant to both ampicillin and tetracycline d. cells that contained the desired vector would be sensitive to both ampicillin and tetracycline e. none of the above

b. cells that contained the desired vector would be resistant to tetracycline but sensitive to ampicillin

15. Glycosphingolipids consist of a ____ with one or more ____ residues in a(n) ____ linkage at the 1-hydroxyl moiety. a. sugar; fatty acids; ester b. ceramide; sugar; β-glycosidic c. ceramide; fatty acid; amide d. glycerol; fatty acids; ester e. none are true

b. ceramide; sugar; β-glycosidic

14. Which of the following alcohols is correctly paired with the functional group that it contains? a. ethanolamine: secondary amine group b. choline: quaternary ammonium group c. inositol: aldehyde and alcohol groups d. glycerol: ether e. none of the above are correct

b. choline: quaternary ammonium group

2. In eukaryotic cells, glycolysis occurs in the ____, and the TCA cycle reactions take place in ____. a. mitochondria; mitochondria b. cytoplasm; mitochondria c. cytoplasm; cytoplasm d. mitochondria; ribosomes e. cytoplasm; ribosomes

b. cytoplasm; mitochondria

3. The ____ of pyruvate to acetyl-CoA is catalyzed by ____. a. dehydration; pyruvate dehydration complex b. decarboxylation; pyruvate dehydrogenase complex c. decarboxylation; pyruvate decarboxylase d. transacylation; pyruvate transacylase e. none of the above.

b. decarboxylation; pyruvate dehydrogenase complex

30. Which of the following would be considered an ω-3 fatty acid? a. linoleic acid: 9,12-octadecadieneoic acid (18:2Δ^9,12) b. eicosapentaenoic acid: 5,8,11,14,17-eicosapentaenoic acid (20:5Δ^5,8,11,14,17) c. γ-linolenic acid: 6,9,12-octadecatrieneoic acid (18:3Δ^6,9,12) d. arachidonic acid: 5,8,11,14-eicosatetraenoic acid (20:4Δ^5,8,11,14) e. none of the above

b. eicosapentaenoic acid: 5,8,11,14,17-eicosapentaenoic acid (20:5Δ^5,8,11,14,17)

30. The enzymes of glycolysis and those of the citric acid cycle are found in which cellular compartments in muscle cells? a. both in the cytoplasm b. glycolysis in cytoplasm and citric acid cycle in mitochondria c. both in mitochondria d. glycolysis in cytoplasm and citric acid cycle in lumen of the endoplasmic reticulum e. both in the lumen of the endoplasmic reticulum

b. glycolysis in cytoplasm and citric acid cycle in mitochondria

10. Shuttle vectors have the property that they: a. contain promoters for the expression of the gene. b. have origins of replication for two different cell types, usually bacteria and yeast. c. are capable of incorporating very large DNA fragments. d. contain more than one antibiotic resistant gene. e. none of the above

b. have origins of replication for two different cell types, usually bacteria and yeast.

35. All are true for pyruvate carboxylase EXCEPT: a. an anaplerotic reaction. b. in mitochondria of plants, but not animals. c. is tetrameric. d. contains covalently bound biotin. e. absolute allosteric requirement for acetyl-CoA.

b. in mitochondria of plants, but not animals.

8. One of the problems with plasmids like pUR278 is that there is no true marker for determining whether or not the plasmid contains the inserted gene since the cloning site does not lie within any specific gene. Which of the following would be an extremely useful tool for rapid selection of those bacteria that have taken up a plasmid with the desired DNA insert? a. look for the production of the lacZ gene by adding X-gal to the growth medium b. include the gene for a fluorescent protein such as GFP in the inserted DNA c. after ligating the DNA insert and plasmid, separate the mixture of DNA molecules by agarose gel electrophoresis to isolate the DNA molecule that corresponds to the size of the plasmid+insert d. look for ampicillin resistance in the transformed cells e. none of the above would be effective

b. include the gene for a fluorescent protein such as GFP in the inserted DNA

23. All of the following are examples of energy transduction EXCEPT: a. dehydrogenase catalyzed reactions b. isomerase reactions c. oxidative phosphorylation d. NAD+- NADH shuttle e. all of the above are correct

b. isomerase reactions

10. Which is NOT true of citrate synthase? a. it catalyzes the first reaction in the TCA cycle b. it is not regulated c. OAA and acetyl-CoA bind to the active sites d. the citrate synthase reaction liberates a relatively large amount of energy e. all of the above are true

b. it is not regulated

34. When carbohydrate intake is low, ____ are formed from acetate units to provide metabolic fuel for the ____ and other tissue. a. fatty acids; liver b. ketone bodies; brain c. ketone bodies; liver d. amino acids; brain e. sterols; heart

b. ketone bodies; brain

25. The cyclization of gluconic acid produces what type of structure? a. lactam b. lactone c. pyranose d. cyclic ether e. none of the above

b. lactone

28. RNA is ____ stable to alkaline hydrolysis than DNA because RNA's vicinal ____ group makes the 3'-phosphodiester bond susceptible to ____ cleavage. a. less; 3'-OH; nucleophilic b. less; 2'-OH; nucleophilic c. more; 2'-OH; electrophilic d. more; 2'-OH; nucleophilic e. more; 3'-OH; electrophilic

b. less; 2'-OH; nucleophilic

15. All are true for cDNA libraries EXCEPT: a. reverse transcriptase synthesizes a DNA strand complement of the mRNA templates. b. mRNA templates are isolated using oligo (dA)-cellulose chromatography. c. linkers are added and the cDNA is cloned into suitable vectors. d. the cDNA are copies from mRNA templates. e. all are true.

b. mRNA templates are isolated using oligo (dA)-cellulose chromatography.

37. All are characteristics of coenzymes EXCEPT: a. carry functional groups. b. maintenance of original structure. c. provide a broader range of catalytic properties. d. can be derived from water-soluble vitamins. e. can serve as an electron carrier.

b. maintenance of original structure.

51. Which of the following enzymes catalyzes an endergonic step of the citric acid cycle? a. citrate synthase b. malate dehydrogenase c. α-ketoglutarate dehydrogenase d. isocitrate dehydrogenase e. none of the above

b. malate dehydrogenase

19. A glycosidic bond would be present in: a. β-D-galactosamine. b. methyl-β-D-glucoside. c. 2-deoxy-α-D-ribose. d. β-D-glucose-6-phosphate. e. α-D-fructose-1, 6-bisphosphate.

b. methyl-β-D-glucoside

21. In eukaryotic cells, DNA is found principally in the nucleus, but it also occurs in ____ and in____. a. ribosomes; mitochondria b. mitochondria; chloroplasts c. chloroplasts; peroxisomes d. peroxisomes; vacuoles e. vacuoles; mitochondria

b. mitochondria; chloroplasts

13. Glycophorin is a membrane protein with: a. multiple transmembrane segments. b. most of the mass oriented outside the surface of the cell. c. about 10% carbohydrate and 90% protein. d. transmembrane β-barrel segments. e. All are true

b. most of the mass oriented outside the surface of the cell.

34. Bacteriorhodopsin affects a light driven ____ proton transport that results in a proton gradient sufficient to drive ____. a. inward; Na+-import b. outward; ATP synthesis c. inward; K+-export d. outward; light emission e. none are true

b. outward; ATP synthesis

22. DNA sequences that are inverted repeats, or ____, have the potential to form a ____ structure known as a ____ if the normal ____ base pairing is replaced by ____ pairing. a. probes; secondary; cruciform; interstrand; intrastrand b. palindromes; tertiary; cruciform; interstrand; intrastrand c. cruciforms; secondary; palindrome; intrastrand; interstrand d. palindromes; tertiary; cruciform; intrastrand; interstrand e. none are true.

b. palindromes; tertiary; cruciform; interstrand; intrastrand

9. The two major phospholipids on the outer leaflet of erythrocytes are: a. phosphatidylcholine and phosphatidylethanolamine. b. phosphatidylcholine and sphingomyelin. c.phosphatidylethanolamine and sphingomyelin. d. phosphatidylserine and sphingomyelin. e. phosphatidylcholine and phosphatidylserine.

b. phosphatidylcholine and sphingomyelin.

27. Which of the following enzymes is responsible for the release of arachidonic acid from membrane phospholipids? a. phospholipase A1 b. phospholipase A2 c. phospholipase B d. phospholipase C e. phospholipase D

b. phospholipase A2

21. Cholesterol is a component of all EXCEPT: a. lipoproteins. b. plant cell plasma membranes. c. membranes of intracellular organelles. d. animal cell membranes. e. all are true.

b. plant cell plasma membranes.

45. Proteoglycans are a group of macromolecules formed from: a. proteases and monosaccharides. b. proteins and glycosaminoglycans. c. proteins and polysaccharides. d. proteases and glycosaminoglycans. e. proteins and glycogen.

b. proteins and glycosaminoglycans.

7. A cyclic hemiacetal with a six-membered oxygen-containing ring is referred to as a(n): a. aldehyde. b. pyranose. c. ketopentose. d. furanose. e. sorbitol.

b. pyranose

13. ssDNA will renature requiring ____ of the DNA strands into a dsDNA and this is called ____ which occurs best if the temperature is ____ Tm but warm enough to promote diffusion of the DNA molecules. a. hydrolysis; reannealing; below b. reassociation; reannealing; below c. reassociation; melting; above d. complementing; solidifying; below e. none are true

b. reassociation; reannealing; below

4. Alkali hydrolysis of triacylglycerols is called ____ and yields ____ and ____. a. triacylation; fatty acids; glycerol b. saponification; fatty alcohols; fatty acids c. triesteration; salts of fatty acids, fatty alcohols d. saponification; salts of fatty acids; glycerol e. none are true

b. saponification; fatty alcohols; fatty acids

29. Nearly all of the calcium ions in muscle are sequestered inside vesicles called: a. mitochondria. b. sarcoplasmic reticulum. c. endoplasmic reticulum. d. Golgi. e. secretory vesicles.

b. sarcoplasmic reticulum.

26. 30S rRNA is a designation of the ____ of the RNA molecule. a. number of sugars b. sedimentation coefficient c. splicing coefficient d. sequence repeats e. splicing number

b. sedimentation coefficient

29. Phylogenetic comparisons of secondary structures of rRNAs from a variety of species reveals ____ structures and____ nucleotide sequences of the rRNAs themselves. a. strikingly similar; high degree of similarity b. strikingly similar; low degree of similarity c. dissimilar; high degree of similarity d. dissimilar; low degree of similarity e. none of the above

b. strikingly similar; low degree of similarity

11. Citrate must be isomerized to isocitrate because the ____ group of citrate is not oxidizable, but the ____ group of isocitrate can be oxidized. a. ketone; primary alcohol b. tertiary alcohol; secondary alcohol c. ketone; secondary alcohol d. aldehyde; primary alcohol e. secondary alcohol; ketone

b. tertiary alcohol; secondary alcohol

6. DNA double helix structure is stabilized by all of the following EXCEPT: a. the sugar-phosphate backbones are oriented in opposite directions. b. the glycosidic bonds holding paired bases are directly across the helix from one another. c. cations such as Mg2+ bind to the anionic phosphates. d. bases stack together through hydrophobic interactions and van der Waals forces. e. appropriate base pairing builds a polymer whose external dimensions are uniform.

b. the glycosidic bonds holding paired bases are directly across the helix from one another.

14. Which of the following is the major advantage of a multi-enzyme complex? a. it's large size enables it to span an entire membrane b. the product of one enzyme is passed directly to the next enzyme without the possibility of diffusion c. multi-enzyme complexes are much less likely to be inhibited d. all of the above e. none of the above

b. the product of one enzyme is passed directly to the next enzyme without the possibility of diffusion

18. Since both glycolysis and gluconeogenesis are spontaneous pathways, which of the following explains how this is true? a. glycolysis uses 10 enzyme catalyzed steps while gluconeogenesis uses 11 b. the three irreversible steps of glycolysis have alternate routes for gluconeogenesis c. glycolysis converts glucose to pyruvate while gluconeogenesis converts pyruvate to glucose d. glycolysis is oxidative while gluconeogenesis is reductive e. glycolysis is catabolic while gluconeogenesis is anabolic

b. the three irreversible steps of glycolysis have alternate routes for gluconeogenesis

6. Which of the following IS NOT a property of integral membrane proteins (intrinsic proteins)? a. they contain both hydrophobic surfaces and hydrophilic surfaces b. they dissociate from the membrane by treatment with salt solutions c. they are exposed to at least one aqueous surface surrounding the membrane d. they are inserted into the membrane and sequestered largely by hydrophobic interactions e. they have significant lateral mobility

b. they dissociate from the membrane by treatment with salt solutions

63. What coenzyme would be required in the following reaction? (pic on other side) a. NAD+ b. thiamine pyrophosphate c. biotin d. lipoic acid e. coenzyme A

b. thiamine pyrophosphate

17. G protein-α-subunits are anchored into membranes by: a. amine-linked myristoyl anchors. b. thioester-linked fatty acyl anchors. c. amide-linked prenyl anchors. d. thioester-linked prenyl anchors. e. amide-linked glycosyl phosphatidylinositol anchors.

b. thioester-linked fatty acyl anchors.

18. The Ras proteins are associated to the membrane via what mechanism? a. thioester-linked fatty acyl anchor b. thioether-linked prenyl anchor c. carboxy terminal ester-linked prenyl anchor d. insertion of a portion of an amphipathic helix into the membrane e. both b and c

b. thioether-linked prenyl anchor

50. Which of the following statements regarding the glyoxylate cycle is true? a. the process takes place in the mitochondria b. two molecules of acetyl CoA can be converted to one molecule of oxaloacetate c. isocitrate dehydrogenase and malate dehydrogenase are not used d. the primary role is to allow for the synthesis of amino acids from fatty acids e. none of the above

b. two molecules of acetyl CoA can be converted to one molecule of oxaloacetate

56. What vitamin is needed for coagulation of blood and what must happen for it to be functional? a. vitamin D, a co-translational modification of serine. b. vitamin K, a posttranslational carboxylation of glutamate. c. vitamin K, a co-translational carboxylation of aspartate. d. vitamin D, a posttranslational glycosylation of serine. e. vitamin E, a posttranslational glycosylation of tyrosine.

b. vitamin K, a posttranslational carboxylation of glutamate.

16. Although present in small amounts in most membranes, glycosphingolipids have a number of cellular functions EXCEPT: a. involvement in nerve impulse transmission. b. water-repellant properties of animal skin. c. tissue and organ specificity. d. cell-cell recognition. e. tissue immunity.

b. water-repellant properties of animal skin.

5. Lipids are the biomolecules of choice for storage of metabolic energy because they: a. are soluble in water. b. yield a large amount of energy upon oxidation. c. are highly oxidized. d. are easily hydrolyzed. e. are amphipathic.

b. yield a large amount of energy upon oxidation.

39. Cellulase is considered a(n) ____. a. α-(1→4) glucosidase b. β-(1→4) glucosidase c. α-(1→6) glucosidase d. β-(1→4) glucosidase e. α-(1→1) glucosidase

b. β-(1→4) glucosidase

33. Inosine, one of the common alternative bases found in RNA, is shown below. How would inosine form hydrogen bonds in a double helical section of RNA? (pic on other side) a. 1 H-bond donor group, 0 H-bond acceptor groups b. 0 H-bond donor groups, 1 H-bond acceptor group c. 1 H-bond donor group, 1 H-bond acceptor group d. 2 H-bond donor groups, 1 H-bond acceptor group e. 1 H-bond donor group, 2 H-bond acceptor groups

c. 1 H-bond donor group, 1 H-bond acceptor group

17. In a sample of double-stranded DNA containing 32% cytosine, the percentage of adenine would be: a. 32% b. 68% c. 18% d. 0% e. insufficient information to answer question

c. 18%

32. If a restriction site of 6 bases starts with 5'-TGG, what are the last three bases in the sequence? a. 5'-ACC-3' b. 5'-GGT-3' c. 5'-CCA-3' d. 5'-TGG-3' e. none of the above

c. 5'-CCA-3'

18. The convention in all notations of nucleic acid structure is to read the polynucleotide chain from the ____ of the polymer to the ____. a. poly U head; poly A tail b. 3'-end; 5'-tail c. 5'-end; 3'-end d. poly-p head; 5'-end e. none are true

c. 5'-end; 3'-end

12. ____ catalyzes citrate isomerization to isocitrate by abstracting ____ from citrate to yield the enzyme-bound intermediate ____, followed by ____ to produce isocitrate. a. Citrate isomerase; CO2; trans-aconitate; carboxylation b. Citrate isomerase; water; trans-aconitate; rehydration c. Aconitase; water; cis-aconitate; rehydration d. Aconitase; CO2; cis-aconitate; carboxylation e. None are true

c. Aconitase; water; cis-aconitate; rehydration

27. The correct sequence of electron transport in the succinate dehydrogenase reaction mechanism is: A. Coenzyme Q (UQ). B. [FAD]. C. iron-sulfur clusters. D. electron transport chain. a. A, B, C, D b. B, C, D, A c. B, C, A, D d. C, B, D, A e. C, D, A, B

c. B, C, A, D

37. All are true for cellulose and α-amylose EXCEPT: a. Both are linear homopolymers of glucose. b. Both have (1→4) linkages. c. Both form extended ribbon most stable conformations. d. Both have extensive intramolecular hydrogen bonding. e. All are true.

c. Both form extended ribbon most stable conformations.

6. Order the coenzymes according to their involvement in the pyruvate dehydrogenase complex. A. NAD+ B. CoA-SH C. TPP D. Lipoate (lipoamide) E. [FAD] a. A, B, C, D, E b. C, B, A, E, D c. C, D, B, E, A d. B, D, E, A, C e. C, E, D, B, A

c. C, D, B, E, A

15. What are the final products of aerobic catabolism? a. pyruvate and H2O. b. acetyl-CoA and CO2. c. CO2 and H2O. d. pyruvate and acetyl-CoA. e. ammonia and O2.

c. CO2 and H2O.

11. The higher the ____ content of a DNA, the ____ the melting temperature, and the ____ the ionic strength, the ____ the melting temperature. a. G:C; higher; higher; lower b. G:C; lower; higher; lower c. G:C; higher; lower; lower d. A:T; higher; higher; lower e. A:T; lower; lower; higher

c. G:C; higher; lower; lower

4. The pyruvate dehydrogenase complex contains three multimeric enzymes (ETA, EPDH, and EDLD). All are properties of EPDH EXCEPT: a. It uses thiamin pyrophosphate as a catalytic coenzyme. b. It oxidatively decarboxylates pyruvate. c. It binds NAD+ in its active site. d. It transfers an acetyl group to lipoamide of ETA. e. It forms a hydroxyethyl-TPP intermediate.

c. It binds NAD+ in its active site.

34. All of the following statements about the nature of glycogen are true EXCEPT: a. It is a polysaccharide used for storage. b. It is a branched polymer of linked glucose residues. c. It has all non-reducing ends. d. The highly branched structure allows the rapid mobilization of glucose during metabolic need. e. It is found primarily in the liver and skeletal muscles.

c. It has all non-reducing ends.

5. The following statements are correct about the reaction catalyzed by the pyruvate dehydrogenase complex EXCEPT: a. it is the link between glycolysis and the TCA cycle b. The activity of the complex is regulated by the phosphorylation of EPDH. c. NAD+ is the direct oxidant of reduced lipoamide. d. An FAD is covalently linked to the EDLD, the lipoamide dehydrogenase component. e. Although EPDH is called "pyruvate dehydrogenase" it is not a dehydrogenase.

c. NAD+ is the direct oxidant of reduced lipoamide.

24. Which of the following is the appropriate source of the DNA polymerase included in the PCR reaction mixture? a. E. coli b. bacteriophage T4 c. Thermus aquaticus d. Drosophila melanogaster e. Human

c. Thermus aquaticus

12. All are true about the relationship between catabolism and anabolism EXCEPT: a. They occur simultaneously. b. Products of one process provide substrates for the other. c. They occur in many of the same organelles. d. The generation of ATP by catabolism provides the energy required by anabolism. e. Anabolism is endergonic while catabolism is exergonic.

c. They occur in many of the same organelles.

11. Which molecule contains an phosphoanhydride bond? a. DNA b. AMP c. UDP d. RNA e. cAMP

c. UDP

12. A genomic DNA library is: a. a collection of short fragments from nuclear DNA digestion. b. arrays of synthetic oligonucleotides used to select for a specific DNA. c. a set of cloned fragments that collectively represent the genes of a particular organism. d. a short segment of DNA whose sequence is complementary to a portion of the DNA of interest. e. a circular DNA molecule of 1 kb to 200 kb found in bacteria and yeast cells.

c. a set of cloned fragments that collectively represent the genes of a particular organism.

6. All of the following are chemoheterotrophs EXCEPT: a. Staphylococci aureus. b. fungi. c. algae. d. animals. e. non-photosynthetic roots.

c. algae.

1. Complete hydrolysis of nucleic acids liberates all of the following EXCEPT: a. 2-deoxyribose from DNA. b. nitrogenous bases. c. amino acids. d. phosphoric acid. e. ribose from RNA.

c. amino acids.

2. Lipids that spontaneously form micelles, monolayers and bilayers have what property? a. waxy b. polar c. amphipathic d. bipolar e. polyisoprenoid

c. amphipathic

16. Which of the following is a commonly used mechanism for anchoring a protein to a membrane? a. attaching a fatty acid to a serine residue to form an ester b. attaching a fatty acid to a methionine residue to form a thioester c. attaching a farnesyl group to a cysteine residue to form a thioether d. attaching a fatty acid to a glutamine residue to form an amide e. none of the above

c. attaching a farnesyl group to a cysteine residue to form a thioether

62. What coenzyme would be required in the following reaction? (pic on other side) a. ADP b. thiamine pyrophosphate c. biotin d. lipoic acid e. coenzyme A

c. biotin

47. ______ 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

c. biotin; thiamine pyrophosphate

12. Urea and formamide are agents that denature dsDNA by a. intercalating between base pairs and disrupting van der Waals interactions. b. forming ionic bonds with the backbone phosphates. c. competing effectively with the H-bonding between the base pairs. d. changing the pH to cause hydrolysis. e. none are true

c. competing effectively with the H-bonding between the base pairs.

18. The terpenes are all EXCEPT: term-73 a. made up of isoprene monomers. b. formed from two or more 2-methyl-1,3-butadiene molecules. c. components of wool wax. d. monomers units linked head to tail. e. all are true.

c. components of wool wax.

17. All of the following are parts of the honeybee's processing of honey EXCEPT: a. producing a small amount of gluconic acid. b. concentrating the sugars to a supersaturated state. c. conversion of some glucose and fructose into sucrose. d. conversion of most of the fructose to the β-D-fructopyranose form. e. producing an emulsion of glucose hydrate and fructose hydrate crystals in a thick syrup.

c. conversion of some glucose and fructose into sucrose

9. Some species can adapt to anaerobic conditions by substituting other electron acceptors for oxygen in their energy-producing pathways and are called: a. aerobes. b. obligate aerobes. c. facultative anaerobes. d. obligate anaerobes. e. none of the above.

c. facultative anaerobes.

16. Honey is characteristically composed predominantly of a. sucrose b. glucose and ribose c. fructose and glucose d. sucrose and sorbitol e. all of the above

c. fructose and glucose

14. Sugar alcohols include all of the following EXCEPT: a. ribitol. b. sorbitol. c. fucose. d. mannitol. e. glycerol.

c. fucose

17. Looking at all of the genes that are activated during a major metabolic shift or during embryogenesis and development of organisms is called: a. fractional expression. b. genetic fractionation. c. functional genomics. d. mutagenesis. e. none of the above.

c. functional genomics.

5. Mannose is an epimer of: a. ribose b. galactose c. glucose d. xylose. e. fructose.

c. glucose

42. Inhibition of the citric acid cycle at isocitrate dehydrogenase increases the levels of citrate and isocitrate that may increase the production of: a. amino acids. b. pyruvate and oxaloacetate. c. glyoxylate and cytosolic acetyl-CoA. d. succinate and fumarate. e. lactate and alanine.

c. glyoxylate and cytosolic acetyl-CoA.

47. The glyoxylate cycle reaction that is catalyzed by malate synthase involves the condensation of acetyl CoA with_____. The mechanism is most similar to the TCA cycle enzyme _____. a. succinate; fumarase b. isocitrate; succinyl-CoA synthetase c. glyoxylate; citrate synthase d. oxaloacetate; aconitase e. acetyl CoA; isocitrate lyase

c. glyoxylate; citrate synthase

45. All are true statements for the glyoxylate pathway EXCEPT: a. the glyoxylate pathway enzymes are found in the glyoxysomes. b. although glyoxysomes are found in germinating seeds, they disappear after a plant begins photosynthesis. c. glyoxysomes contain all of the enzymes for the glyoxylate cycle. d. bypasses the oxidative-decarboxylation steps of the TCA cycle. e. isocitrate is routed through isocitrate lyase and malate synthase.

c. glyoxysomes contain all of the enzymes for the glyoxylate cycle.

27. People with high blood pressure have high blood levels of an endogenous Na+, K+-ATPase ____ that results in ____of sodium and calcium in cells lining the blood vessel wall. a. inhibitor; decrease b. stimulator, decrease c. inhibitor; accumulation d. stimulator; accumulation e. none of the above

c. inhibitor; accumulation

29. Characteristics of the oxidation of malate to oxaloacetate (OAA) include all EXCEPT: a. catalyzed by malate dehydrogenase. b. uses NAD+ as an electron acceptor. c. is very exergonic. d. results in higher levels of malate than oxaloacetate. e. is structurally and functionally similar to lactate dehydrogenase.

c. is very exergonic.

48. ____ functions to couple acyl-group transfer and electron transfer during oxidation and decarboxylations of ____. a. biotin; propionate b. lipoate; propionate c. lipoate; α-keto acids d. TPP; α-keto acids e. TPP; acetyl-CoA

c. lipoate; α-keto acids

4. Which of the following is an example of a unilamellar vesicle? a. monolayer b. bilayer c. liposome d. micelle e. an inside out micelle

c. liposome

20. Which of the following disaccharides contains an α (1→4) O-glycosidic bond? a. sucrose b. lactose c. maltose d. cellobiose e. cellulose

c. maltose

51. Which of the following statements is true regarding glycogen? a. the branches are formed by α(2→6) glycosidic bonds b. glycogen is the primary energy storage molecule for animals c. most of the glycosidic bonds are α(1→4) d. glycogen is considered a heteropolysaccharide e. none of the above are true

c. most of the glycosidic bonds are α(1→4)

10. cAMP and cGMP are ____ with phosphate esterified as a cyclic ____ and are important as____ of cellular metabolism. a. nucleotides; phosphodiesters; inhibitors b. nucleotides; phosphomonoesters, regulators c. nucleotides; phosphodiesters, regulators d. nucleosides; phosphomonoesters, stimulators e. all of the above

c. nucleotides; phosphodiesters, regulators

29. Because osmotic pressure depends only on ____, the osmotic pressure is greatly reduced by formation of polysaccharide molecules from monosaccharide molecules. a. molecular weight b. number of hydroxyl groups c. numbers of molecules d. numbers of hydrogen bonds e. none are true

c. number of molecules

25. The succinate dehydrogenase mechanism involves the ____ of succinate, which is exergonic and can be used to provide for the ____. a. oxidation; reduction of NAD+ b. reduction; oxidation of NAD+ c. oxidation; reduction of [FAD] d. reduction; oxidation of [FAD] e. none are true

c. oxidation; reduction of [FAD]

21. Energy is generally extracted from phototrophs and chemotrophs by: a. hydrolysis reactions. b. condensation-cleavage reactions. c. oxidative-reduction reactions. d. acid-base reactions. e. phosphorylation reactions.

c. oxidative-reduction reactions.

25. ____ are attached to hnRNAs and mRNAs after transcription has been completed and is essential for efficient translation and stability of the mRNAs. a. exons b. entrons c. poly(A) tails d. poly(U) tails e. All are true

c. poly(A) tails

7. All are steps in the sequence for construction of a chimeric plasmid EXCEPT: a. annealing the ends of the vector and foreign DNA. b. cutting the source of the foreign DNA with a restriction endonuclease. c. reannealing the ends of the vector back together. d. cutting the vector plasmid with the same restriction endonuclease. e. none of the above.

c. reannealing the ends of the vector back together.

36. All of the following are a coenzyme or a precursor of a coenzyme EXCEPT: a. thiamin. b. riboflavin. c. retinol. d. niacin. e. biotin.

c. retinol.

22. RT-PCR differs from basic PCR in that: a. reverse temperatures are used for annealing and transcription. b. transcription is reversed from 5' to 3' ends. c. reverse transcriptase is used to synthesize a cDNA strand complementary to an RNA strand. d. reverse transcripase is used to synthesize an RNA strand from the DNA strand. e. none of the above.

c. reverse transcriptase is used to synthesize a cDNA strand complementary to an RNA strand.

2. Which of the following sugars is an aldopentose? a. galactose b. ribulose c. ribose d. xylulose e. mannose

c. ribose

9. Which of the following is correctly paired with its most prevalent cyclization product? a. fructose: pyranose b. glucose: furanose c. ribose: pyranose d. galactose: does not cyclize e. none of the above

c. ribose: pyranose

22. Hydropathy plots for transport proteins are utilized to reveal: a. amino acid residues which may be highly modified. b. amino acid residues which may be directly involved in facilitated transport. c. stretches of amino acid residues that make up hydrophobic regions, which may be directly associated with the lipid bilayer. d. amino acid residues which are hyper-reactive due to their location. e. whether there is interaction between N-terminal and C-terminal amino acids.

c. stretches of amino acid residues that make up hydrophobic regions, which may be directly associated with the lipid bilayer.

21. All of the following disaccharides are reducing sugars EXCEPT: a. lactose. b. maltose. c. sucrose. d. cellulose. e. isomaltose.

c. sucrose

39. It is crucial that regulation occur at pyruvate dehydrogenase because: a. pyruvate kinase is reversible. b. lactate dehydrogenase is the only other enzyme to use pyruvate. c. the product acetyl-CoA is committed to oxidation in the citric acid cycle or fatty acid biosynthesis. d. alanine aminotransferase would use the pyruvate. e. all of the above.

c. the product acetyl-CoA is committed to oxidation in the citric acid cycle or fatty acid biosynthesis.

15. Which of the following statements regarding the structure of DNA is correct? a. the two strands are parallel. b. the two strands are held together by intrachain hydrogen bonds. c. the two strands have complementary base pairing. d. the hydrogen bonding that holds the helix together is always between two purines or between two pyrimidines. e. the ratio of adenine to guanine is the same in all organisms.

c. the two strands have complementary base pairing.

2. Which of the following statements correctly describes the process of DNA sequencing by chain termination? a. the enzyme DNA polymerase is used to form a primer that binds to the template DNA b. in order to effectively sequence the DNA, the dideoxynucleotides must be present at a higher concentration than the deoxynucleotides c. the use of 4 unique fluorescent labels attached to the dideoxynucleotides allows for a single reaction to be run d. the dideoxynucleotides lack a 5'-OH and therefore can not serve as acceptors in nucleotide addition e. both B and C are correct

c. the use of 4 unique fluorescent labels attached to the dideoxynucleotides allows for a single reaction to be run

59. The cofactors NAD+, NADPH and FAD all have what common chemical feature? a. they all contain a guanine nucleotide b. they all contain a sulfhydryl group that acts as a nucleophile c. they all pick up or release two electrons during an oxidation/reduction reaction d. they all can be used for phosphorylation of enzyme substrates e. none of the above

c. they all pick up or release two electrons during an oxidation/reduction reaction

25. In the Na+, K+-ATPase mechanism, ATP is involved in all EXCEPT: a. binding E2 to change conformation to E1 and release of K+ b. binding E1 to facilitate binding of Na+ c. transferring a phosphate group to make sodium phosphate d. hydrolysis to ADP and E1-P e. none of the above

c. transferring a phosphate group to make sodium phosphate

5. A method used to insert or transform cells with a plasmid is to: a. add the DNA to bacterial cells that have been lightly treated with lysozyme to produce "holes" in the cell wall. b. add the DNA to a heated suspension of cells at 42°C. c. treat the bacteria with Ca2+, add the DNA, and briefly heat to 42°C. d. incubate the DNA with the cells overnight at 4°C. e. mixing plasmids with an extract of broken cells.

c. treat the bacteria with Ca2+, add the DNA, and briefly heat to 42°C.

33. When dietary carbohydrate consumption exceeds the energy needs of the individual, excess carbohydrate is converted to ____ and ____ for energy storage. a. amino acids; glucose b. fructose; triacylglycerols c. triacylglycerols; glycogen d. glycogen; protein e. none of the above.

c. triacylglycerols; glycogen

17. The structure is an example of a(n): (pic on other side) a. diacylglycerol. b. triacylglycerol. c. wax ester. d. eicosanoid. e. monoacylglycerol.

c. wax ester.

50. Which of the following best describes the glycosidic bond below? (pic on other side) a. β(2→4) b. α(1→3) c. α(1→4) d. β(1→3) e. α(2→4)

c. α(1→4)

26. The succinate dehydrogenase catalyzed reaction involves dehydrogenation ____ to a carbonyl group and is ____ to yield a ____ double bond. a. β,β; electrophilic; trans b. α,β; electrophilic; cis c. α,β; stereospecific; trans d. β,γ; stereospecific; cis e. none are true

c. α,β; stereospecific; trans

24. The reaction below is catalyzed by: (pic on other side) a. desmolase. b. 17α-hydroxylase. c. 17,20-lyase. d. 17β-hydroxysteroid dehydrogenase. e. none of the above are true.

d. 17β-hydroxysteroid dehydrogenase.

31. In the TCA cycle, ____ oxidation(s) use(s) NAD+ as the oxidizing agent while ____ oxidation(s) use(s) FAD as the oxidizing agent. a. 0; 4 b. 1; 3 c. 2; 2 d. 3; 1 e. 4; 0

d. 3; 1

34. Which of the following restriction sites would provide staggered 3'ends? The restriction site in each sequence is shown with an arrow. a. 5'-T↓TCGAA-3' b. 5'-GTT↓AAC-3' c. 5'-CCC↓GGG-3' d. 5'-CTGCA↓G-3' e. none of the above

d. 5'-CTGCA↓G-3'

20. What is the nucleotide sequence of the DNA strand that is complementary to 5'-ATCGCAACTGTCACTA-3'? a. 5'-TAGCGTTGACAGTGAT-3' b. 5'-UAGUGACAGUUGCGAU-3' c. 5'-TAGCGTTGACAGTGAT-3' d. 5'-TAGTGACAGTTGCGAT-3' e. 5'-ATCACTGTCAACGCTA-3'

d. 5'-TAGTGACAGTTGCGAT-3'

5. What is the nucleotide sequence of the DNA strand that is complementary to 5'-ATCGCAACTGTCACTA-3'? a. 5'-TAGCGTTGACAGTGAT-3' b. 5'-UAGUGACAGUUGCGAU-3' c. 5'-TAGCGTTGACAGTGAT-3' d. 5'-TAGTGACAGTTGCGAT-3' e. 5'-ATCACTGTCAACGCTA-3'

d. 5'-TAGTGACAGTTGCGAT-3'

49. In a biotin-dependent carboxylation, _____ provides the energy for activation of ____. a. acetyl CoA; carbon dioxide b. ATP; lysine amine group c. NADH; bicarbonate d. ATP; bicarbonate e. acetyl CoA; carboxyl group

d. ATP; bicarbonate

25. From the following types of organic molecules, the order of most reduced to most oxidized is: A. aldehyde B. hydrocarbon C. CO2 D. alcohol E. carboxylic acid a. A, B, C, D, E b. B, E, A, D, C c. C, B, E, A, D d. B, D, A, E, C e. C, D, E, B, A

d. B, D, A, E, C

24. Glucuronic acid is formed by oxidation of which carbon of glucose? a. C-1 b. C-2 c. C-4 d. C-6 e. both a and b

d. C-6

42. Pantothenic acid is the vitamin portion of ____. a. ATP b. FAD c. pyridoxal phosphate d. Coenzyme A e. TPP

d. Coenzyme A

16. The correct sequence of procedures in the Southern blotting (hybridization) technique is: A. hybridization with radioactive probe. B. agarose gel electrophoresis and visualize bands. C. transfer (blot) to nitrocellulose filter. D. digest DNA with restriction nucleases. E. expose filter to X-ray film, develop and observe. a. B, A, C, E, D b. D, C, B, A, E c. C, D, B, E, A d. D, B, C, A, E e. A, B, C, D, E

d. D, B, C, A, E

26. Ouabain, an effective inhibitor of Na+, K+-ATPase, exhibits all of the following characteristics EXCEPT: a. It has a basic steroid structure. b. It contains an unsaturated lactone ring at C-17. c. It binds on the extracellular surface of Na+, K+-ATPase. d. It binds tightly to the enzyme/ATP complex in producing the inhibition. e. It is a cardiac glycoside.

d. It binds tightly to the enzyme/ATP complex in producing the inhibition.

19. All are true for linking number EXCEPT: a. It is a basic parameter characterizing supercoiled DNA. b. L = T + W. c. It is the number of times that two strands are intertwined providing both strands remain covalently intact. d. L = 40 in a relaxed circular DNA duplex of 400 bp. e. All are true.

d. L = 40 in a relaxed circular DNA duplex of 400 bp.

4. The enantiomer of D-mannose would be: a. D-galactose. b. L-glucose. c. D-glucose. d. L-mannose. e. L-arabinose.

d. L-mannose

13. Nucleotide triphosphates and nucleotide diphosphates often form stable complexes with: a. Na + b. Fe +3 c. K + d. Mg +2 e. None of the above.

d. Mg +2

41. What is a characteristic difference between FAD and NAD+? a. NAD+ is a stronger oxidizing agent than FAD. b. Only FAD participates in oxidation-reduction reactions. c. NAD+ binds tightly to its enzyme while FAD only binds loosely. d. NAD+ transfers two electrons while FAD can transfer one or two. e. NAD+ is re-oxidized easily by molecular oxygen while FAD is not.

d. NAD+ transfers two electrons while FAD can transfer one or two.

34. When acetyl-CoA levels exceed the ____ supply, allosteric activation of ____ by ____ raises the oxaloacetate (OAA) levels for condensation with acetyl-CoA to form ____. a. citrate; citrate synthase; acetyl-CoA; citrate b. malate; malate dehydrogenase; ATP; citrate c. OAA; citrate synthase; acetyl-CoA; isocitrate d. OAA; pyruvate carboxylase; acetyl-CoA; citrate e. Acetyl-CoA; pyruvate carboxylase; citrate; acetyl-CoA

d. OAA; pyruvate carboxylase; acetyl-CoA; citrate

52. Amylose and glycogen are both glucose polymers, yet they have somewhat different properties. What is one important difference between them? a. One is made with D-glucose and the other with L-glucose b. One is used as a structural polymer in insects; the other for energy in plants c. One contains α glycosidic bonds while the other contains β glycosidic bonds d. One is a linear polymer while the other is highly branched e. none of the above explain the difference between amylose and glycogen

d. One is a linear polymer while the other is highly branched

26. ____ is typical of the oligosaccharide components found in beans, etc., that are not digested in the stomach, but are digested by bacteria in the intestines causing flatulence. a. Melezitose b. Amygdelin c. Laetrile d. Stachyose e. Dextrantriose

d. Stachyose

22. Whcih of the following is NOT a characteristic of aerobic catabolic pathways? a. an example of a catabolic pathway is the conversion of hexoses to 3-carbon compounds b. ADP is phosphorylated to ATP as a result of such pathways. c. NADH is a common product of such pathways d. Water is oxidized to O2 e. generally, the energy produced by such pathways is greater than the energy required to activate the substrates for the pathway

d. Water is oxidized to O2

1. All are characteristics of metabolism EXCEPT: a. a process which synthesizes either energy or complex cellular substances. b. a process of intermediates. c. the conversion of food energy into energy of motion. d. a free-flow unregulated process. e. a process responding to the momentary energy requirements of a cell.

d. a free-flow unregulated process.

17. The definition of an amphibolic pathway is: a. a pathway found in animals living in both land and water. b. a pathway that is carried out both in water and organic solvents. c. a pathway found on both sides of the mitochondrial membrane. d. a pathway that is both anabolic and catabolic in nature. e. all of the above.

d. a pathway that is both anabolic and catabolic in nature.

50. Pyruvate + CoA + NAD+ → ____ + CO2 + ____ a. oxaloacetate; ATP b. malonyl CoA; NADH + H+ c. methylmalonyl CoA; biotin d. acetyl CoA; NADH + H+ e. succinyl CoA; NAD+

d. acetyl CoA; NADH + H+

1. In the TCA cycle, carbon enters the cycle as ____ and exits as ____ with metabolic energy captured as ____, ____ and____. a. malonate; water; NADH; ATP; NADPH b. acetyl-CoA; CO2; NADH; ATP; NADPH c. succinyl-CoA; CO2; ATP; NADH; NADPH d. acetyl-CoA; CO2; ATP; NADH; [FADH2] e. malonyl-CoA; water; NADH; [FADH2]; ATP

d. acetyl-CoA; CO2; ATP; NADH; [FADH2]

28. The most promising vector for human gene therapy is ____. a. yeast b. E coli c. human papilloma virus d. adenovirus e. bacteriophage λ

d. adenovirus

6. The formation of cyclic structures in sugars with creation of an additional asymmetric center results from an alcohol reacting with a(n): a. secondary alcohol. b. phosphate group. c. thiol group. d. aldehyde or ketone. e. primary alcohol.

d. aldehyde or ketone.

1. Which of the following explains why it is often easier to sequence a gene rather than sequence the corresponding protein? a. DNA sequencing can be performed on picogram quantities of DNA b. DNA is composed of only 4 different monomers while proteins are composed of 20 different monomers c. restriction endonucleases can be used to cut DNA at specific sequences to generate DNA fragments that can easily be sequenced d. all of the above e. both B and C are correct

d. all of the above

14. In phosphoryl group transfer reactions, the ____ of the nucleotide serves as an information symbol, channeling the nucleotide to appropriate metabolic activities. a. sugar b. diphosphate anhydride c. sugar-phosphate ester d. base e. none are true

d. base

28. rRNA strands exhibit which of the following: a. instrastrand sequence complementarity b. highly folded patterns including many stem-loop structures c. an anticodon loop d. both a and b e. a, b and c

d. both a and b

20. The function of DNA topoisomerases is: a. packaging DNA into nucleosomes. b. forming cruciform DNA. c. unwinding G:C rich areas in DNA. d. breaking one or more strands of DNA, winding them tighter or looser, and rejoining the ends. e. promoting DNA hybridization.

d. breaking one or more strands of DNA, winding them tighter or looser, and rejoining the ends.

54. What are the principal minerals in the human body? a. iron and chloride b. sodium and potassium c. calcium and sodium d. calcium and phosphorus e. sulfur and phosphorus

d. calcium and phosphorus

23. All are plant steroids EXCEPT: a. campesterol. b. stigmasterol. c. β-sitosterol. d. cortisol. e. all are true.

d. cortisol.

49. Which of the following monosaccharides is an aldose? (pic on other side) a. a b. b c. c d. d e. none of the above

d. d

53. Which of the following would be the correct Haworth projection for β-D-talose (linear form is shown on the left)? (pic on other side) a. a b. b c. c d. d e. none of the above

d. d

10. The hyperchromic shift that occurs when dsDNA is ____ is a(n) ____ in absorption at ____ nm. a. methylated; increase; 220 b. methylated; decrease; 260 c. denatured; decrease; 260 d. denatured; increase; 260 e. melted; decrease; 280

d. denatured; increase; 260

10. In eukaryotic cells phospholipids, glycolipids and cholesterol are synthesized by enzymes located in the ____ and ____, and flow of these components to other membranes in the cell is mediated by ____. a. plasma membrane; mitochondria; osmosis b. endoplasmic reticulum; Golgi; osmosis c. plasma membrane, Golgi; lipid transfer proteins d. endoplasmic reticulum; Golgi; lipid transfer proteins e. endoplasmic reticulum; plasma membrane; flippases

d. endoplasmic reticulum; Golgi; lipid transfer proteins

26. Which of the following steroid hormones is NOT correctly defined? a. testosterone: an androgen involved in male sexual development b. progesterone: a progestin that controls the menstrual cycle. c. cortisol: a glucocorticoid that controls nutrient metabolism d. estradiol: a progestin involved in female sexual development e. all are correctly defined

d. estradiol: a progestin involved in female sexual development

38. The transport of glutamine across a membrane was measured, and the results obtained are presented in the following table. What type of transport does Gln exhibit? (pic on other side) a. primary active transport b. secondary active transport c. passive diffusion d. facilitated diffusion e. cannot determine from the given data

d. facilitated diffusion

5. All are characteristics of pyrimidines EXCEPT: a. six-membered ring. b. heterocyclic. c. conjugated. d. fused five membered rings. e. two nitrogens separated by a carbonyl.

d. fused five membered rings.

22. The steroid hormones that participate in the control of carbohydrate, protein and lipid metabolism are the: a. progestins. b. mineralocorticoids. c. estrogens. d. glucocorticoids. e. androgens.

d. glucocorticoids.

27. Cellulose is homopolysaccharide composed of ______ linked together by ______ glycosidic bonds. a. galactose; β-(1→4) b. galactose; α-(1→4) c. glucose; β-(1→4) d. glucose; α-(1→4) e. none of the above

d. glucose; α-(1→4)