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BIOCHEMISTRY 1. Which of the following single-base DNA gene coding changes is least likely to significantly affect the function of resulting protein? (Harper pages 361-363) A. B. C. D. 2. Which of the following is a property of enhancer elements? (Harper pages 384-385) A. B. C. D. 3. Saturated fatty acids increase fluidity. Cholesterol is an amphipathic molecule. The inner and outer sheets are symmetrical to each other. They contain transport proteins, which are mainly peripheral. Which of the following defines the specificity of hormone activity in a cell? (Harper page 435) A. B. C. D. 6. Chromatin remodelling Alternative splicing RNA editing Capping of the mRNA Which of the following is true of biological membrane structure? (Harper pages 415-421) A. B. C. D. 5. They do not work located downstream of the promoter. They could work when located long distances from the promoter. Upon activation, they could repress transcriptional rate. They are proteins binding to DNA sequences. Which of the following is considered as a transcriptional regulation control? (Harper pages 383) A. B. C. D. 4. Missence mutation resulting to histidine-to-glutamic acid change Silent mutations in the third codon base Frameshift mutation Nonsense mutation The synthesis of the hormone in the target cell The presence of the hormone receptor The upregulation of the hormone receptor in a cell Absence of other target cells adjacent to hormone-producing cells Which of the following is true of hormones? (Harper pages 437-38) A. Hormones with intracellular receptors are usually hydrophilic. B. Lipophilic hormones need transport proteins. C. Cathecholamines and steroid hormones act via a plasma membrane receptor. D. Steroid hormones are derivatives of amino acids. 1 7. Which vitamin is essential for one-carbon metabolism? (Harper page 494) A. B. C. D. 8. Thiamine Riboflavin Niacine Folic acid Which of the following correctly characterize a component of the extracellular matrix? (Harper 535-541) A. Collagen type IV, a component of the basement membrane, form compact bundles. B. Elastin is essential for cell-cell communication. C. Fibronectin is involved mainly in cell adhesion and signaling. D. Laminin acts intracellularly as a major component of the cytoskeleton. 9. Which of the following is NOT correctly paired? (Harper page 593) A. B. C. D. 10. IgA: found in secretions IgM: transplacental passage IgG: opsonization IgE: allergic responses Which of the following statements characterizes ATP? (Harper page 84) A. B. C. D. It is used in the synthesis of DNA. It contains 3 phosphate bonds for energy storage. It is used to drive thermodynamically unfavorable reactions. It is produced mainly by substrate level phosphorylation. 11. Enzymes, as biological catalysts accelerate velocity of reactions by: A. lowering the free energy of activation of reactions B. increasing transition state of reactants and products C. lowering the net energy change between initial and final states of the reaction D. increasing the equilibrium constant (Keq) of the reaction 12. A general class of enzymes that join molecules by creating a new chemical bond at the expense of ATP hydrolysis A. lyase B. isomerase C. ligase D. hydrolase 13. An enzyme catalyzing the reaction: lecithin + cholesterol -- fatty acid cholesterol ester + lysolecithin is classified as: A. oxidoreductase B. lipase C. transferase D. hydrolase 14. The Michaelis Menten constant is equal to substrate concentration when: initial velocity is ½ Vmax Vmax is doubled Km= ½ substrate concentration Km/Vmax = 1 2 15. The kinetic parameter that reflects the affinity of the enzyme for its substrate is called: A. Vmax B. Q10 C. Km D. Kcat 16. Double reciprocal plot of the Michaelis Menten equation is called: A. Hanes-Wolf B. Eadie Hofstee C. Lineweaver Burk D. Briggs-Haldane 17. In the Lineweaver Burk plot, the slope of the line is equal to: A. -1/Km B. Km/Vmax C. 1/Vmax D. 1/S 18. Which statement is true about competitive inhibition? A. Inhibitor binds to the allosteric site of the enzyme B. Km is constant while Vmax decreases C. Usually the inhibitor structurally resembles the normal substrate D. Both the Km and Vmax decrease 19. Serum enzymes are elevated following tissue injury and death due to: A. enzyme induction secondary to stimulation of protein synthesizing machinery of the cell B. allosteric enzyme activation by positive activators C. increased cell membrane permeability and leakage of enzymes into blood D. proteolytic activation of proenzymes or zymogens 20. Which of the following coenzymes is not appropriately paired with the enzymatic reaction it is associated with? E. tetrahydrofolate- transamination F. biocytin-carboxylation G. NAD- dehydrogenation H. Coenzyme A- transacylation 21. The active form of Vitamin B12 coenzyme: A. 5’-deoxyadenosylcobalamin B. hydrocobalamin C. aquocobalamin D. cobamide 22. In Bioenergetics, the amount of energy available for the performance of useful work is termed: A. entropy B. free energy C. enthalpy D. equilibrium energy 3 23. During biological oxidations, reduced coenzymes such as NADH and FADH2 generate energy when oxidized thru the: A. Krebs Cycle B. Electron Transport Chain C. Cytochrome P450 system D. Embden Meyerhof Pathway 24. The final acceptor of electrons in the Respiratory Chain is: A. cytochrome oxidase B. coenzyme Q C. iron sulfur center D. oxygen 25. Substrate level phosphorylation differs from oxidative phosphorylation in that: A. oxidative phosphorylation synthesizes ATP via the Electron Transport Chain B. substrate level phosphorylation only takes place in the cytosol C. oxidative phosphorylation is coupled to a direct transfer of high energy ~Pi from a high energy compound to ADP D. Substrate level phosphorylation is more energy efficient per molecule of substrate oxidized 26. Which of the following affects biological oxidation by dissociating mitochondrial respiration from phosphorylation? A. 2,4 dinitrophenol B. B. rotenone C. C. antimycin D. cyanide 27. Which of the following statements is correct regarding digestion of carbohydrates? A. Digestion of dietary polysaccharides takes place to a significant extent in the stomach due to acid hydrolysis. B. Digestion initially takes place in the mouth through the action of - amylase. C. -1,4 glycosidic linkages in cellulose. D. The final end products of digestion are all glucose molecules from dietary carbohydrates 28. In man, glucose from dietary cellulose could not be available for energy because: A. ce B. human diet does not have a significant amount of cellulose C. man inherently lacks enzyme to hydrolyze cellulose D. cellulose is not made up of glucose units 29. A 3 month old infant develops diarrhea and abdominal discomfort a following a milk formula. However feeding history revealed that he was able to tolerate breast feeding and the same milk formula at birth. The most likely condition is A. - galactosidase deficiency B. Milk allergy C. Lactose malabsorption D. Secondary lactose intolerance 4 30. The major pathway of glucose metabolism that exists in all cells is the: A. Pentose Phosphate Pathway B. Citric Acid Cycle C. Uronic Acid Pathway D. Embden Meyerhof Pathway 31. Hexokinase differs from glucokinase in which aspect? A. Glukokinase has a higher affinity to glucose B. Hexokinase is induced by insulin C. Glucokinase phosphorylates glucose to glucose 6 phosphate D. Hexokinase is inhibited by glucose 6 phosphate 32. The end product of glycolysis in exercising muscle and red blood cells is: A. pyruvic acid B. acetic acid C. lactic acid D. acetoacetic acid 33. The most important positive regulator of the committed step of glycolysis is the availability of A. fructose 1,6 bisphosphate B. ATP C. Citrate D. fructose 2,6 bisphosphate 34. True of the The Malate Aspartate Shuttle A. can be considered as an anaplerotic reaction B. less energetically efficient than the C. transports NADH from the cytosol into the mitochondria for oxidative phosphorylation D. provides reducing equivalents for reductive biosynthesis of fats 35. The initial step in the TCA Cycle is catalyzed by: A. pyruvate dehydrogenase B. lactate dehydrogenase C. citrate synthase D. -keto-glutarate dehydrogenase 36. The Hexose Monophosphate Shunt is metabolically significant to nucleic acid metabolism because it: A. provides NADPH B. furnishes pentose phosphates C. is an alternative pathway for glycolysis D. stabilizes structure of DNA 37. The rate limiting step in the Pentose Phosphate Pathway is catalyzed by: A. hexokinase B. glucose-6 phosphate dehydrogenase C. 6- phosphogluconolactonase D. transketolase 38. Which of the following enzymatic reaction is common to both glycolysis and gluconeogenesis? A. hexokinase B. pyruvate carboxylase C. phosphofructokinase 1 D. phosphotriose isomerase 5 39. The inherent absence of this enzyme prevents muscle glycogenolysis to maintain glucose homeostasis: A. glycogen phosphorylase B. glucose- 1- phosphatase C. glucose-6-phosphatase D. UDP-Glucose pyrophosphorylase 40. Glycogen synthesis is activated while glycogenolysis is inhibited when: A. glucagon/ insulin ratio is elevated B. glycogen synthase is covalently modified by phosphorylation C. cyclic AMP dependent protein kinase is activated D. glycogen synthase I predominates over glycogen synthase D 41. Mannose and Fructose enter the mainstream of carbohydrate metabolism via: A. Citric Acid Cycle B. Embden Meyerhoff Pathway C. Hexose Monophosphate Shunt D. Glyoxylic Acid Cycle 42. Fatty acids enter the mitochondrial matrix for oxidation in what form? A. acyl-CoAs through active transport B. as free fatty acids C. following conversion to carnitine D. complexed with carnitine as acyl-carnitine 43. The number of reduced electron carriers generated when one mole of palmitate is subjected to oxidation: A. 2 FADH2 and 3 NADH + H+ B. 3 FADH2 and 2 NADH + H+ C. 7 FADH2 and 7 NADH + H+ D. 5 FADH2 and 5 NADH + H+ 44. Majority of the reducing equivalents necessary for fatty acid biosynthesis are generated during conversion of: A. 1,3 bisphosphoglycerate to 3 phosphoglycerate B. pyruvate to malate C. glucose 6-phosphate to 6 phosphogluconate D. 6 phosphogluconate to ribulose 5-phosphate 45. How many moles of NADPH + H+ can be derived from the pathway utilized in the transport of acetyl CoA out of the mitochondria? A. 8 moles B. 10 moles C. 12 moles D. 14 moles 46. The site of action of the NSAIDS is: A. thromboxan synthase B. prostaglandin cyclooxygenase C. lipoxygenase D. prostacyclin synthase 6 47. Hepatocytes contribute to the overall body content of ketone bodies primarily because of the absence of: A. β-ketothiolase necessary to hydrolyze acetoacetyl CoA B. HMG-CoA lyase C. HMG-CoA synthetase D. 3-ketoacyl-CoA transferase or acetoacetate succinyl CoA transferase 48. The principal plasma carrier of dietary triacylglycerols is: A. serum albumin B. LDLs C. HDLs D. chylomicrons 49. Activation of lipoprotein lipase requires which apoprotein? A. Apo E B. Apo B-100 C. Apo C-II D. Apo B-48 50. VLDLs are synthesized in the liver for transport of which of the following to the peripheral tissues? A. triacylglycerols B. apoproteins for HDL synthesis C. LDL receptors D. apo B-100 51. The committed step of cholesterol biosynthesis is catalyzed by this enzyme: A. squalene synthase B. HMG CoA reductase C. mevalonate kinse D. HMG CoA lyase 52. High dietary intake of cholesterol leads to: A. increased HMG CoA reductase synthesis B. decreased apo B-100 synthesis C. decreased ACAT activity D. decreased LDL receptor synthesis 53. Several of the enzymes of cholesterol biosynthesis require which of the following cofactors? A. biotin B. NADPH C. FADH2 D. TPP 54. The molecule that helps stabilize the action of pancreatic lipase on dietary lipids: A. colipase B. chenodeoxycholic acid C. cholic acid D. enteropeptidase 7 55. Source of the nitrogen atoms required for animal metabolism can be directly obtained from: A. atmospheric nitrogen B. NO2 C. ammonia D. nitric oxide 56. Aside from urea, the main circulatory system carrier of nitrogen atoms destined for excretion by the kidney is: A. glutamate B. asparagine C. alanine D. glutamine 57. A deficiency in the abilty to secrete enterokinase leads to which of the following? A. abnormally low levels of intestinal zymogens B. abnormally low levels of active intestinal proteases C. abnormally low levels of undigested proteins in lower GIT D. increase plasma levels of serum amylase 58. Transamidation reaction include which of the following? A. formation of liver glutamate from α-ketoglutarate B. formation of liver glutamine from glutamate C. formation of liver asparagine from aspartate D. formation of liver oxaloacetate from alanine 59. The important cofactor for the transaminases: A. pyridoxal phosphate B. tetrahydrofolate C. biocytin D. tetrahydrobiopterin 60. The production of alanine by peripheral tissue, especially by the muscle, is primarily dependent on: A. allosteric effectors of ALT B. intracellular levels of pyruvate C. intracellular levels of glutamate D. intracellular levels of NADH 61. Nitrogen of muscle alanine can be derived from tissue ammonia through this enzyme action: A. glutamate dehydrogenase B. alanine dehydrogenase C. glutamine synthetase D. alanine synthetase 62. Sulfur for cysteine synthesis is derived from : A. sulfites B. H2S C. Coenzyme A D. methionine 63. Severe PKU and shortened life span is a result of: A. excess dietary phenylalanine B. excess dietary tyrosine C. deficiency of dihydrobiopterin reductase 8 D. deficiency of tetrahydrofolate 64. Serine is synthesized by: A. transamination of an amino acid with α-ketoglutarate as an amino acceptor B. transamination of an α-ketoacid derived from TCA C. transamination of an α-ketoacid derived from EMP D. modification of an essential amino acid 65. Lysine is an essential amino acid because: A. animals cannot make the lysine carbon skeleton B. the ε-amino group of lysine cannot be formed by an aminotransferase C. the α-carboxylic cannot be added to urocanate D. lysine cannot be subjected to deamidation 66. Amino acids that are strictly ketogenic: A. lysine and leucine B. leucine and isoleucine C. valine and isoleucine D. tyrosine and tryptophan 67. Choose the correct precursor-product relationship from the following: A. tyrosine is a precursor to dihydroxyphenylalanine B. tyrosine is a precursor to melatonin C. melatonin is a precursor of serotonin D. dopamine is a precursor to norepinephrine 68. The Watson-Crick model or the B-form of DNA is typified by: A. 12 base pairs per helical turn B. a smaller number of purines than pyrimidines C. bases located in the interior of the right-handed helix D. two single strands that run in the 5’ 3’ direction 69. Guanine-cytosine (G-C) base pairs in a DNA molecule are more stable to denaturation than adenine-thymine (A-T) pairs because: A. adenine and thymine have bulkier structures than guanine and cytosine B. A-T base pairs exhibit less electron clouds around them C. G-C base pairs contain more hydrogen bonds than A-T pairs D. the phosphodiester bonds among G-C base pairs are weaker 70. DNA is distinguished from RNA by: A. a high content of modified bases B. its component sugar, ribose C. its single stranded structure D. the presence of thymine instead of uracil 71. Anticancer drugs like 5-fluorouracil and 6-mercaptopurine act against malignant cells by: A. being incorporated into DNA before replication B. causing the denaturation of DNA in cancer cells C. inactivating protein synthesis D. inhibiting the enzymes that synthesize thymidylic acid 9 72. Which of the following is a nucleotide? A. uracil B. cytidine C. guanosine D. adenylic acid 73. Which vitamin is essential in the synthesis of purine nucleotides? A. ascorbic acid B. folic acid C. niacin D. thiamin 74. Which clinical condition does not involve a defect in purine metabolism? A. adenosine deaminase deficiency B. gout C. Lesch-Nyhan syndrome D. orotic aciduria 75. Salvage reactions that generate purine and pyrimidine nucleosides and nucleotides are characterized as: A. involving the same enzymes as in de novo synthesis B. more efficient than nucleotide synthesis from new precursors C. providing greater output of purines and pyrimidines D. requiring less energy than does the de novo synthesis 76. The enzyme that catalyzes the committed step of purine nucleotide de novo pathway: A. carbamoyl phosphate synthetase I B. glutamine amidophosphoribosyl transferase C. carbamoyl phosphate synthetase II D. aspartate transcarbamoylase 77. In the management of gout, allopurinol is given to inhibit xanthine oxidase, the enzyme that catalyzes the synthesis of: A. allantoate B. ammonia C. urea D. uric acid 78. The correct flow of genetic information according to the Central Dogma of Molecular Biology is: A. replication -----> transcription ----> translation B. replication -----> translation ----> transcription C. transcription ---- > replication ----> transcription D. translation ----> replication ----> transcription 79. Transfer RNA (tRNA) as an adaptor molecule serves to: A. carry the nucleotide sequences that will dictate the amino acid to be synthesized B. hold the promoter site that will be recognized by the polymerase C. recognize the triplet codon in mRNA via its anti-codon arm D. synthesize the amino acid to be incorporated into the peptide 10 80. Degeneracy of the Genetic Code means that: A. an amino acid can only be decoded by a single codon B. a single codon encodes only one amino acid C. multiple codons may encode the same amino acid D. with time, codons degenerate into senseless code 81. The final product of gene expression is: A. amino acid B. nucleotide C. polynucleotide D. protein 82. Normal growth and development of cells are controlled by genes known as: A. leader genes B. non-coding genes C. proto-oncogenes D. transforming genes 83. The type of mutation that involves the substitution of a purine base with another purine base is: A. transition B. transposition C. transpyrimidation D. transversion 84. This mineral helps guard against DNA damage as a cofactor of glutathione: A. iron B. manganese C. selenium D. zinc 85. A tool in molecular biology in which a DNA sequence of interest is exponentially amplified in vitro by repeated cycles of enzymatic DNA synthesis is: A. DNA sequencing B. in situ hybridization C. Northern blotting D. polymerase chain reaction 86. In the construction of recombinant DNA, which enzyme is used to cut DNA at precise base sequences? A. DNA polymerase B. DNA-RNA exonuclease C. restriction endonuclease D. T4 DNA ligase 87. In recombinant DNA technology, antibiotic resistance genes in plasmids are used to: A. control copy number in bacteria B. facilitate transformation of host cells C. provide a marker for start of replication D. select and screen for recombinant DNA clones 11 88. The pain felt by a patient with an enlarging malignant tumor is partly contributed by the: A. exaggerated metabolism of nutrients by the tumor cells B. loss of enzymes for glucose oxidation in cancer tissue C. release of cytokines such as IL-1 and IL-6 by the tumor cells D. overgrowth of blood vessels in the interior of the cancer mass 89. Malignancy may be naturally prevented if the mutated cancer gene was repaired: A. after gene expression B. before DNA replication C. following transcription D. shortly after DNA synthesis 90. With persistence of a mutation in cells during organogenesis, the resulting event is: A. development of cancer B. inactivation of genetic disorders C. occurrence of physical malformations D. promotion of sterility 91. To specifically identify the mutation in the affected DNA segment in a patient with cancer, which blot transfer method should be used? A. Northern B. Southern C. Southwestern D. Western 92. The enzyme, Taq polymerase is used in Polymerase Chain Reaction (PCR) because it: A. facilitates annealing of primers B. is resistant to heat denaturation C. promotes DNA polymerization D. provides optimum condition for DNA synthesis 93. A 60-year-old woman has developed red, roughened skin in sun-exposed areas over the past 2 years. She also has a chronic, watery diarrhea. On physical examination she exhibits memory loss with confusion. These findings are most consistent with which of the following vitamin deficiencies? A. Thiamine B. Pyridoxine C. Niacin D. Vitamin A 94. A clinical study is performed involving dietary iron metabolism in adults. It is observed that intestinal absorption of iron can be enhanced in patients with iron deficiency anemia by supplementing their diet with another nutrient. Which of the following vitamins is most likely to have this effect? A. D B. E C. C D. B3 12 95. A 6-year-old child was born at term, with no congenital anomalies. She is now only 70% of normal body weight, though she shows dependent edema of the lower extremities as well as an enlarged abdomen. Her flaking skin shows irregular areas of depigmentation, hyperpigmentation, and desquamation. These findings are most suggestive of which of the following nutritional problems? A. Marasmus B. Kwashiorkor C. Niacin deficiency D. Vitamin A Deficiency 96. A 41-year-old man has had increasing dyspnea for the past year. On physical examination he has diffuse crackles at lung bases. A chest x-ray shows pulmonary edema and cardiomegaly. Echocardiography shows an ejection fraction of 40%. Laboratory studies show hemoglobin 14 g/dL, hematocrit 42%, and WBC count 8320/microliter. A deficiency in which of the following vitamins is most likely to produce these findings? A. A B. B1 C. B2 D. K 97. A 7-year-old child has complained of pain in his legs for the past year. On physical examination, there is bowing deformity of his lower extremities. Plain film radiographs of his lower legs shows widened epiphyses and bowing of tibiae. Bone mineral density appears normal, consistent with failure of osteoid matrix formation. Which of the following vitamin deficiencies is this child most likely to have? A. D B. E C. C D. B3 98. A 28-year-old man has a history of multiple and recurrent pulmonary infections since childhood. He also has noted foul smelling stools for the past 10 years. Laboratory studies show an elevated sweat chloride test. He has a quantitative stool fat of 10 g/day. A deficiency state involving which of the following nutrients is most likely to develop in this patient? A. Vitamin B1 B. Vitamin D C. Calcium D. Vitamin A 99. A clinical study is performed to compare the risk for health problems in obese persons with a BMI OF 35, compared with a control group of persons with a BMI between 20 and 25. Persons in these two groups are followed for 20 years. Which of the following conditions is most likely to appear equally in both groups? A. Cholelithiasis B. Cirrhosis C. Hypertension D. Diabetes mellitus 13 100. A 15-year-old girl has been under a physician's care for the past year after diagnosis of anorexia nervosa. Her BMI is now 18. On physical examination she has cheilosis. Laboratory studies show hemoglobin 13.7 g/dL, hematocrit 41.0%, MCV 88 fL, platelet count 191,055/microliter, and WBC count 4930/microliter. Her serum glucose is 66 mg/dL. Which of the following nutrient deficiencies is most likely to cause this patient's findings? A. Riboflavin B. Vitamin C C. Folic Acid D. Iron 101. The metabolic function of the pentose phosphate pathway is to: A. act as a source of ADP biosynthesis. B. generate NADPH and pentoses for the biosynthesis of fatty acids and nucleic acids. C. participate in oxidation-reduction reactions during the formation of H2O. D. provide intermediates for the citric acid cycle. 102. The FNRI Philippine RENI Committee 2002 recommends the following protein intake: A. 1.14 g/kg DBW/day B. 2.14 g/kg DBW/day C. 3.14 g/kg DBW/day D. 4.14 g/kg DBW/day 103. Number of moles of ATP generated from the complete oxidation of pyruvate as it undergoes the pyruvate dehydrogenase reaction and the Kreb’s cycle is: a. 12 c. 14 b. 13 d. 15 Page 113 Harper’s 26th Edition Chapter 16 104. Which of the following enzymes when deficient wil result in the accumulation of gangliosides in patients suffering for Tay Sach’s Disease? a. glucocerebrosidase c. sphingomyelinase b. aryl sulfatase d. hexosaminidase th Page 203 Harper’s 26 Edition Chapter 24 105. Which of these is deficient in Cori’s disease? a. glucose-6-phosphate b. glycogen phosphorylase Page 152 Harper’s 26th Edition Chapter 18 c. branching enzyme d. debranching enzyme 106. Just before breakfast, what is the source of glucose in the body? a. glucose c. ketones b. glycogen d. fatty acids Page 102,107-108 Harper’s 26th Edition Chapter 13 107. For every mole of glucose that goes through the glycolytic pathway, what is the net number of pyruvate generated? a. one c. three b. two d. four Page 136-144 Harper’s 26th Edition Chapter 17 14 108. Which of these is the primaryfunction of the Pentose Phosphate Pathway? a. generation ATP b. NADPH generation c. NADPH generation and production of ribose residues d. Provision of ribose residues of nucleotide and nucleic acid synthesis Page 163-168 Harper’s 26th Edition Chapter 20 109. Which enzyme generates NADPH + H needed to reduce GSSG: a. glutathione reductase c. aldehyde dehyrogenase b. glucose 6PO4 dehydrogenase d. lactate dehydrogenase th Page 156-165 Harper’s 26 Edition Chapter 19 110. Glucose 6 phosphate dehydrogense deficiency is characterized by which one of the following? a. accumulation of glucose -6-phosphate in the tissue b. decreased formation of NADPH c. increased synthesis of reduced glutathione d. may manifest as hemorrhagic anemia Page 169-170 Harper’s 26th Edition Chapter 20 111. The Citric acid cycle as the final common pathway in fuel metabolism provides greatest amount of energy by being directly linked to: a. glycerophosphate shuttle c. glycolysis b. malate aspartate shuttle d. electron transport chain Page 130-133 Harper’s 26th Edition Chapter 16 112. Cyanide poisoning is very fatal. This is bacuse cyanide has this effect of the Electron Transport Chain: a. inhibits complex III b. inhibits cytochrome oxidase c. uncouples oxidative phosphorylation d. ienhance the transport of electrons Page 92 Harper’s 26th Edition Chapter 12 113. At high concentration of blood glucose, as in uncontrolled diabetes mellitus, hemoglobin reacts with glucose to form this compound which can be assayed to monitor glycemic control a. methemoglobin b. hemochrome c. glycosylated hemoglobin d. hemin Page 47 Harper’s 26th Edition Chapter 6 114. The precursor of the sugar-phosphate moieties in the de novo synthesis of both purine and primidine nucleotide is: a. glucose 1 phosphate b. glucose 6 phosphate c. ribose 1 phosphate d. ribose 5 phosphate Page 286-292 Harper’s 26th Edition Chapter 33 115. The highest reservior of calories in muscle tissues is: a. Fats c. glycogen b. proteins d. ketone bodies Page574-576 Harper’s 26th Edition Chapter 49 15 116. cAMP exert its effect as a second messenger by: a. inducing release of cytokines b. activating Protein Kinase C c. activating cyclic adenylase d. activating Protein Kinase A Page 457-468 Harper’s 26th Edition Chapter 43 117. Deficiency in the intake of carbohydrates and fats can lead to: a. increase in protein requirements b. increase intake of calories c. increase deposition of fats d. decrease in the catabolism of body proteins Page 478-479 Harper’s 26th Edition Chapter 44 118. Gluconeogenesis is the major source blood sugar during: a. the fed state c. prolonged fasting b. periods between meals d. early refed state Page 158-161 Harper’s 26th Edition Chapter 19 119. Melatonin is a specialized product of tryptophan that is involved with a. pigment formation c. circadian rhythm b. vasodilatation d. thyroid gland secretion th Page 267 Harper’s 26 Edition Chapter 31 120. The receptor involved in the G-protein coupled signal transduction pathway: a. tyrosine kinase receptor c. β adrenergic receptor b. guanylyl cyclase receptor d. janus kinase receptor Page 459,464-465 Harper’s 26th Edition Chapter 43 121. Dinitrophenol (DNP) and other uncouplers which uncouple oxidation and phosphorylation are useful weight losing agents. They prevent ATP sysnthesis in the Electron Transport Chain by which of the following mechanism? a. Electron Transport is blocked b. Protons build up in the intermembrane space c. There is reduced availability of ADP d. The electrochemical gradient is dissipated Page 95-96 Harper’s 26th Edition Chapter 12 122. The most active form of vitamin D is: a. 1,25 dihydroxycholecalciferol c. ergocalciferol b. vitamin D3 d. 7- dehydrocalciferol Page 484-486 Harper’s 26th Edition Chapter 45 123. Plant fat is high in unsaturated fatty acids compared to animal fat. Which one of the following characteristics BEST describes unsaturated fatty acids in contrast saturated fatty acids? a. lower rate of oxidation b. lower rate of melting point c. less water soluble d. more solid at room temperature Page 144 Harper’s 26th Edition Chapter 14 16 124. This is the mechanism of action by which penicillin kills bacterial cells: a. it inhibits bacterial DNA replication b. it acts as an allosteric inhibitor to the enxzyme reverse transcriptase c. it is an analogue of D-phe-D-phe effectively preventing the synthesis of tetrahydrofolates d. it covalently binds to the active site of the enzyme for cell wall synthesis Page 371-372 Harper’s 26th Edition Chapter 38 125. An attack of acute asthma has been attributed to leukotrienes. Which of the following statements is TRUE regarding leukotrienes? a. produced mainly in the nervous tissue b. components of slow reacting substance of anaphylaxis c. descrease vascular permeability d. inhibit the release of lysosomal enzymes Page 194-196 Harper’s 26th Edition Chapter 23 126. This statement accurately describes Vitamin K: a. Menaquinone-7 is the major form of Vitamin K found in plants b. It is found only in green leafy vegetables while intestinal bacteria are not able to synthesize it c. It functions as a cofactor to a carboxylase that acts on glutamate residues of clotting factor precursors proteins d. It main function is to protect the erythrocytes Page 486 Harper’s 26th Edition Chapter 45 127. Bilirubin is an important endproduct during the course of hemolysis. Which of the following statements is TRUE regarding bilirubin? a. excreted from the liver in the form of bilirubin diglucuronides b. conjugation mainly it takes place in the kidneys c. unconjugated bilirubin is readily excreted in the urine d. unconjugated hyperbilirubinemia due to complete obstruction of the common bile ducts is generally accompanied by increased urobilinogen in the urine Page 280-284 Harper’s 26th Edition Chapter 32 128. Kwashiorkor occurs when there is: a. lack of calories in the diet b. lack of calories from protein in the diet c. lack of carbohydrates and protein in the diet d. lack of all the macro and micro nutrients in the diet Page 237,478-479 Harper’s 26th Edition Chapter 28 , 44 129. Cancer can be attributed to mutation in the DNA. A mutation that converts an amino acid codon to a stop codon is: a. silent c. missense b. frameshift d. nonsense Page 362 Harper’s 26th Edition Chapter 38 130. The process by which a polypeptide’s destination in the cell is determined by which of these? a. Codons c. signal peptides b. molecular chaperones d. signal recognition particles Page 498,503-504,508 Harper’s 26th Edition Chapter 46 17 131. Which of the following histones is uniquely associated with the linker DNA? a. H3 c. H4 b. H1 d. H2A th Page 314-315 Harper’s 26 Edition Chapter 36 132. Which of the following is a nucleoside? a. guanylic acid c. guanosine 5’-monophosphate b. dUMP d. cytidine th Page 286-287 Harper’s 26 Edition Chapter 33 133. Which of the following about the salvage pathway of purine nucleotide synthesis is correct? a. Deficiency of hypoxanthine-guanine phosphoribosyl transferase is the cause of Lesch-Nyan syndrome b. The rate limiting enzyme is PRPP amidotransferase c. The donor of the ribose 5-phosphate is the HMP shunt d. The salvage pathway for the free bases require more ATP than the novo sysnthesis of purine nucleotide Page 294 Harper’s 26th Edition Chapter 34 134. An individual who has fasted for more than 24 hours will have an increased production of which amino acids in his tissues? a. aspartate and glutamine b. glutamate and asparagine c. valine, isoleucine and leucine d. glutamine and alanine Page 14-20 Harper’s 26th Edition Chapter 3 135. Which amino acid is purely ketogenic ? a. leucine c. isoleucine b. tryptophan d. proline Page 15,259-260 Harper’s 26th Edition Chapter 3,30 136. Kwashiorkor occurs when there is: a. lack of calories in the diet b. lack of calories from protein in the diet c. lack of carbohydrates and protein in the diet d. lack of all the macro and micro nutrients in the diet Page 478-479 Harper’s 26th Edition Chapter 44 137. This amino acid is the source of most of the blood glucose during starvation: a. glutamine c. glutamate b. alanine d. aspartate Page 236 Harper’s 26th Edition Chapter 27 138. Allopurinol is used in gout bacause it is an allosteric inhibitor of xathine oxidase which is responsible for synthesizing this excretory metabolite of purines: a. allanton c. urea b. uric acid d. ammonia Page 301 Harper’s 26th Edition Chapter 35 18 139. The catecholamines, epinephrine and dopamine are synthesized from this amino acid: a. tyrosine c. arginine b. isoleucine d. threonine Page 445 Harper’s 26th Edition Chapter 140. Which of the following is the most important role of amino acids in the body? a. source of energy b. precursor of nonprotein nitrogen containing substances c. building blocks of tissue protein d. precursor glucose Page 249 Harper’s 26th Edition Chapter 30 141. Most of the ammonia that are used for the synthesis of urea are directly derived from the deamination of: a. leucine c. isoleucine b. aspartic acid d. glutamic acid Page 243-244 Harper’s 26th Edition Chapter 29 142. A person suffering from gout should decrease his intake of: a. bread c. egg b. banana d. sardines th Page 229 Harper’s 26 Edition Chapter 26 143. Most of the function membranes are accomplished by: a. proteins c. carbohydrates b. phospholipids d. cholesterol th Page 416-417 Harper’s 26 Edition Chapter 41 144. Which statements is BEST describes the arrangement of proteins and lipids in membranes? a. Protein form a continous sheet on either side of the phospholipid bilayer b. Proteins occur in the lipid bilayer as discontinous particles c. Protein molecules are sandwiched between the exoplasmic and cytoplasmic lipid monolayers d. Lipid molecules “float” on a sea proteins Page 416-417 Harper’s 26th Edition Chapter 41 145. Excessive ingestion of raw eggwhite is detrimental because it inhibits this step in extramitochondrial lipogenesis: a. formation of malonyl CoA c. reduction step b. binding of malonyl to acyl carrier protein d. deacylation reaction Page 173-174 Harper’s 26th Edition Chapter 21 146. Gelatin has a high collagen content. It is not a good source of protein because: a. collagen contains a limited variety of amino acids b. collagen cannot be digested c. too much collagen causes brittle bones d. collagen contains more sugars than amino acids Page 38 Harper’s 26th Edition Chapter 5 19 147. Semi-conservative replication of DNA means: a. DNA systhesis occurs one strand at a time b. Each new DNA strand forms a pair with the template strands c. The two new DNA strands pair with each other d. Duplication occurs in opposite direction in two strands Page 306-307 Harper’s 26th Edition Chapter 35 148. Which of the following is the BEST describes the action of 5 FU in the treatment of cancer? a. inhibits synthesis of DNA b. inhibits protein synthesis c. depletes the cancer cells of necessary nutrients like vitamins d. depletes the cancer cells of required oxygen Page 328-330 Harper’s 26th Edition Chapter 36 149. Which one of the following is true regarding RNA? a. Messenger RNA contain peculiar bases b. The codon is found in trasfer RNA c. Ribosomal RNA contain the anticodon d. Transfer RNA carries the amino acid Page 306-312,341-357 Harper’s 26th Edition Chapter 35,37 150. During DNA replication, which enzyme joins Okazaki fragments? a. topoisomerase c. DNA ligase b. RNAase II d. helicase th Page 328 Harper’s 26 Edition Chapter 36 151. Degeneracy of the genetic code denotes the existence of: a. multiple codons for a single amino acid b. codons consisting only of 2 bases c. base triplets that do not code for any amino acid d. codons that include one or more of the “unusual” bases Page 359 Harper’s 26th Edition Chapter 38 152. In the normal resting state of humans, muscles will mainly use up energy provided by: a. carbohydrates c. fats b. branced chain amino acids d. muscle glycogen Page 574-576 Harper’s 26th Edition Chapter 49 153. Familial hypercholesterolemia is due to a. deficiency or defective LDL receptors b. mutation on HMG-CoA reductase c. increased dietary intake of cholesterol d. decreased excretion of cholesterol Page 228 Harper’s 26th Edition Chapter 26 154. Which of the following is the most metabolically active plasma lipid? a. nonesterified fatty acid c. free cholesterol b. lecithin d. glucocerebroside th Page 57 Harper’s 26 Edition Chapter 7 155. Deficiency of lipoprotein lipase will result in a increased plasma level of which of the following? a. chylomicron remnant c. LDL b. VLDL d. HDL Page 125,126,207-208 Harper’s 26th Edition Chapter 15,25 20 156. Which of the following is needed for the transport of long-chain fatty acids from the cytosol to the mitochondrial matrix? a. carnitine c. glutathione b. S-adenosylmethionine d. phosphoadenosine phosphosulfate Page 180-187 Harper’s 26th Edition Chapter 22 157. Major enzyme that digest dietary triacylglycerol a. lingual lipase c. lipoprotein lipase b. pancreatic lipase d. hormone sensitive lipase Page 475-476 Harper’s 26th Edition Chapter 44 In the liver cholesterol is mainly disposed by: a. being exported as HDL b. being exported as VLDL c. being secreted in the bile as free cholesterol d. being converted to bile acids Page 225-227 Harper’s 26th Edition Chapter 26 158. 159. Which is the immediate source of energy of ATP synthesis? a. electron transfer to O2 c. ADP and Pi b. electrochemical gradient d. solar energy th Page 96-97 Harper’s 26 Edition Chapter 12 160. The link between the catabolic and anabolic reactions in the energy cycle is: a. ATP c. H+ b. O2 d. NADH Page 82-85 Harper’s 26th Edition Chapter 10 161. Which of the following is a function of pyridoxal phosphate? a. prosthetic group of transaminases b. lowers plasma cholesterol c. a coenzyme to many dehydrogenases d. adds hydride ion to the pyridine ring Page 50,491 Harper’s 26th Edition Chapter 7,45 162. What is the role of oxygen in cellular respiration? a. source of electrons to be passed along the respiratory chain b. final receptor of electrons in the respiratory chain c. transporter of electrons from cytosol to mitochondrial matrix d. cofactor of ATP synthase Page 92-101 Harper’s 26th Edition Chapter 12 163. Which vitamin is solely synthesized by bacteria and is thus absent from all plants? a. Biotin c. Folic acid b. Ascorbic acid d. Riboflavin Page 494-495 Harper’s 26th Edition Chapter 45 164. This vitamin is required for the synthesis of neurotransmitters like epinephrine: a. Niacin c. Pyridoxine b. Ascorbic acid d. Riboflavin Page495-496 Harper’s 26th Edition Chapter 45 21 165. Deficiency of this mineral is prevalent among pregnant women living in mountainous areas: a. iron c. copper b. iodine d. magnesium Page 447-449 Harper’s 26th Edition Chapter 42 166. Which of the ff. accumulates in carnitine deficiency in humans ? A. glycogen B. odd-numbered fatty acids * C. triglycerides D. sphingolipids 167. Which regulatory action involves a reversible covalent modification of an enzyme? A. allosteric modulation B. competitive inhibition C. association of apoenzyme with a cofactor D. phosphorylation of Ser hydroxyl on the enzyme * 168. The Ping-pong mechanism of enzyme kinetics applies to which of the reactions? A. one-substrate B. bisubstrate * C. multiple substrate D. hydrolytic 169. Enzymes hasten the rate of chemical reactions through which of the ff. ? A. covalent modification of coenzymes and reactants B. enhancing proximity and local concentration of substrates C. decreasing the free energy of activation * D. increasing the over-all free energy change of the reaction 170. What is the role of oxygen in electron transport system ? A. accepts electrons from FADH2 B. the final acceptor of electrons * C. a mobile electron carrier D. donates electron to water 171. Which of the ff. BEST explains why oxidation of FADH2 produces less ATP than NADH? A. FADH2 enters ETS via complex II * B. FADH2 transfers less electrons through ETS than NADH C. Electrons from FADH2 are not transferred to oxygen D. inner mitochondrial membrane is impermeable to FADH2 172. Which of the ff. BEST applies to Isoelectric ph of a protein? A. ph is physiologic B. net charge is zero * C. protonation is maximum D. ionization is maximum 173. What kind of a reaction is interconversion of aldose and ketose ? A. dehydration B. reduction C. oxidation D. isomerization * 22 174. In the over-all scheme of human metabolism, which organ plays impt role? A. brain B. liver * C. muscle D. kidney 175. Which of these enzymes is important in protein digestion ? A. ptyalin B. trypsin * C. invertase D. pancreatic amylase 176. The beta pleated sheet of a protein is classified as which level of protein ? A. primary C. tertiary B. secondary * D. super secondary 177. What is the cause for the lactic acidosis that develops in thiamine deficiency? A. conversion of pyruvate to acetyl-CoA is blocked * B. conversipon of pyruvate to oxaloacetate is blocked C. the transketolase reaction that transfers 3-carbon units is blocked D. the transaldolase reaction has increased activity 178. Which of the ff. statements BEST describes collagen? A. left handed helix B. 2 left handed alpha helices C. double helical structure D. triple helix * 179. Which of these BEST explains the role of HCL in the stomach? A. kills H. pylori organisms B. denatures proteins * C. ideal ph for amylase action D. stimulates pancreatic juice sec’n 180. Which of the ff. bonds stabilizes the primary structure of a protein? A. hydrogen * B. disulfide C. ionic D. peptide 181. Which of the ff. are products of the action of salivary amylase on glycogen? A. sucrose B. maltose * C. galactose D. fructose 182. A zwiterion is a molecule that contains which of the following? A. a cation and anion * C. polar and non-polar groups B. more than one cation D. more than one anion 183. Which of the ff. is most important source of glucose during early fasting? A. liver triglyceride C. muscle protein B. hepatic glycogen * D. muscle glycogen 23 184. A young infant, who was nourished by synthetic formula, had sugar in blood & urine. This compound gave positive reducing sugar test but negative with glucose oxidase test. Which of the ff. compounds is MOST likely to be present in infant’s blood & urine? A. glucose C. Sorbitol * B. fructose D. maltose 185. In normal resting state of humans, muscles will mainly use up energy that is provided by which of the ff.? A. carbohydrates C. fats * B. muscle glycogen D. amino acids 186. The anemia that develops in patients on anti-malarial therapy may be due to deficiency of enzymes that belong to which metabolic pathway? A. Embden-Mayerhoff C. hexose monophosphate * B. Kreb’s TCA D. Kreb’s-Hanseleit 187. Which of the ff is the primary function of the Pentose Phosphate pathway? A. ATP production B. NADPH generation C. NADPH generation & production of ribose units * D. Provision of ribose units for nucleotide/ nucleic acid synthesis 188. Which of the ff, is the major metabolic substrate required by RBC? A. Glycerol C. fructose B. free fatty acids D. glucose * 189. Which of the ff. is true of the TATA box? A. binds to anti-codon C. encodes repressor proteins B. binds RNA polymerase * D. located in first structural gene 190. SRS-A, the slow reacting substance of anaphylaxis, is composed of which of the ff? A. thromboxanes C. leukotrienes * B. prostaglandins D. prostacyclins 191. The regulation of cholesterol synthesis primarily occurs at which enzymatic site? A. 3-hydroxy-3-methylglutaryl CoA synthase B.3-hydroxy-3-methylglutaryl CoA lyase C.3-hydroxy-3-methylglutaryl CoA reductase * D.3-methyl-3-hydroxylglutaryl CoA oxidase 192. What is the major source of reducing equivalents used for fatty acid syn? A. pentose phosphate pathway * B. Embden-Mayerhoff pathway C. the tricarboxylic acid cycle D. Pyruvate dehydrogenase pathway 193. What is the role of aspirin in the treatment of rheumatoid arthritis? A. inhibits the release of arachidonic acid B. directly neutralizes prostaglandins & thromboxanes C. inactivates cyclooxygenase * D. shuts down the synthesis of all eicosanoid 24 194. Patients suffering from familial defect in Apo B 100 have significantly elevated levels of plasma LDL’s. Which is the major reason for this? A. inability of LDL to interact with the LDL receptor * B. inability of LDL to activate lipoprotein lipase C. inability of LDL to activate cholesterol transfer protein D. LDL interaction with LDL receptors fail to stimulate endocytosis 195. What is the pharmacological benefit of the drug – Lovastatin ? A. inhibits intestinal absorption of dietary cholesterol B. inhibits hepatic production of VLDL C. inhibits HMG-CoA reductase * D. absorbs bile acids, increasing their rate of elimination in the feces 196. In an average adult, which % of body protein is turned over on a daily basis? A. 1 – 2 % * C. 5 – 6 B. 3 – 4 % D. 7 – 8 % 197. Which vitamin combines with opsin to form the visual pigment in the eye ? A. A * C. E B. D D. K 198. Which of the following is the cause of muscle fatigue following vigorous exercise? A. sodium and potassium imbalance B. the utilization of ATP C. accumulation of ADP and PI D. accumulation of lactate * 199. Which intermediate of pyrimidine biosynthesis is common to the urea cycle? A. ornithine C. carbamoyl phosphate * B. citrulline D. carbamoyl aspartate 200. Which of these is a function of nonsense codons? A. they code for non-essential amino acids B. they are responsible for degeneracy of the genetic code C. they base pair with the anticodons D. they may be used in the cell as termination signals * 201. Which phase of protein synthesis does the release of newly synthesized polypeptide from the ribosome take place? A. initiation C. release B. elongation D. termination * 202. Which of the ff. directs the polypeptide’s ultimate destination in the cell ? A. codons C. signal peptides * B. molecular chaperones D. signal recognition particles 203. What is the primary action of methotrexate, a chemotherapeutic agent ? A. displaces cells of folate * C. inhibits phosphorylation of free bases B. inhibits cellular kinase activity D. inhibits synthesis of nucleotides 204. Which of these is the first reaction in the metabolism of all sugars ? A. hydrolysis C. isomerization B. proteolysis D. phosphorylation * 25 205. Which site on the operon is the site of RNA polymerase binding ? A. operator C. promoter * B. regulator D. structural 206. What is the cellular site of synthesis of messenger RNA ? A. nucleus C. mitochondria B. cytosol D. Ribosome * 207. Which of the following BEST applies to transfer RNA ? A. largest of RNA specie C. exists in at least 20 diff forms * B. has no secondary structure D. assoc. w/ histones in cytosol 208. Which of the ff. is the biological function of DNA synthesis ? A. production of normal RNA’s C. prevents mutation B. production of normal proteins D. assures viability of the specie * 209. During RNA synthesis, DNA template sequence 5’ TpApGpCp 3’ would be transcribed to produce which of the ff. sequences ? A. 5’- TpApCpGp- 3’ C. 3’- ApUpCpGp-5’ B. 3’- GpCpTpAp- 5’ D. 5’- GpCpUpAp-3’ * 210. Which of the ff. refer to sequential order of nucleotides in a polypeptide? A. primary structure * C. tertiary structure B. secondary structure D. quaternary structure 211. Which of the ff. enzymes in replication functions as proof-reading device? A. polymerase enzyme C. 5’ exonuclease B. 3’ exonuclease * D. nuclease 212. Which of these constitute the second level of organization of DNA? A. nucleosome * C. double helix DNA B. chromosome D. condensed metaphase chromosome 213. Which of the ff. BEST describes Okazaki fragments? A. fragments of DNA attached to an initiator component B. fragments of continuous DNA which eventually are joined to form DNA C. fragments of DNA that are copied in direction away from replic’n fork * D. synthesized fr. 5’ to 3’ & proceeds in same direction as replication fork 214. The antimetabolite, 5-FU inhibits DNA replication by which mechanism? A. intercalates into the DNA B. cross-links adjacent thymines in the DNA C. inhibts production of deoxythymidine monophosphate * D. cross-links adjacent guanine residues in the DNA 215. Which posttranscriptional processing prevents 5’ exonuclease attack? A. splicing reactions B. B.addition of extra COOH groups C. poly A tail * D. 7 methylguanosine triPO4 216. Which of the ff. reactions does RNA-directed DNA polymerase catalyze? A. synthesis of DNA complimentary to the RNA strand * B.synthesis of DNA complimentary to template DNA strand C. removal of wrong nucleotide inserted during DNA synthesis D.synthesis of an RNA that is complimentary to RNA template 26 217. During protein synthesis, which reads information in mRNA & transfers AA to a growing polypeptide chain? A. messenger RNA C. heterogenous nuclear RNA B. ribosomal RNA D. transfer RNA * 218. What is the cause of polyuria in diabetes mellitus ? A. overdrinking of water because of polydipsia B. decreased ADH activity C. osmotic diuresis * D. decreased aldosterone activity 219. Which is TRUE about methemoglobinemias? A. There is increased activity of methemoglobin reductase. B. It can result as a side-effect of sulfonamides. C. Increased reduction of Fe3+ of methemoglobin to Fe2+ occurs. D. There is absence of the Bohr effect. Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., pp. 46-47. 220. One of the following is a saturated fatty acid: A. Oleic acid B. Linolenic acid C. Palmitic acid D. Arachidonic acid Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 123. 221. One of the following statements is true of the structure CH3(CH2)4CH=CHCH2CH=CH(CH2)7COOH: A. It is a saturated fatty acid with 18 C atoms. B. Its common name is linolenic acid. C. It has two double bonds located at C 9 and C 12. D. Its other name is 18:3c9,12. Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 122. Lipid Metabolism 222. Which of the following is TRUE of fatty acid synthase enzyme complex? A. It can synthesize two 18 carbon atom fatty acids simultaneously. B. It is composed of two polypeptide chains but each monomer is an active enzyme. C. FAS enzyme complex has seven sub-units with catalytic activities. D. The monomers are arranged in a head – to – tail configuration. Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., pp. 196197. 223. The phosphopanthetheine side chain is part of which sub-unit of the fatty acid synthase enzyme complex ? A. acetyl transacylase C. acyl carrier protein B. ketoacyl synthase D. malonyl transcylase Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 196. 224. Deficiency of this phospholipid results to Respiratory Distress Syndrome of the newborn: A. phosphatidylinositol C. phosphatidylserine B. phosphatidylinositide D. dipalmitoyl-lecithin Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 125. 27 The committed step for the β – oxidation of fatty acids is inhibited by increased concentration of: A. acetyl-CoA C. malonyl-CoA B. carnitine D. palmitoyl – CoA Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 195. 225. 226. The complete ATP yield of a saturated C16 fatty acid is: A. 106 C. 110 B. 108 D. 112 Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p.189. 227. Which condition accelerates ketogenesis? A. high carbohydrate diet B. Increased [NAD+]/[NADH] ratio C. low [beta-hydroxybutyrate] D. decreased [Insulin]/[glucagon] ratio Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., pp. 192193. 228. Ketone bodies can be utilized by extra-hepatic tissues because of this enzyme: A. beta-hydroxybutyrate dehydrogenase C. HMG-CoA lyase B. HMG-CoA synthase D. succinyl CoA acetoacetate CoA transferase Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 191. 229. Accelerated ketogenesis occurs in which situation? A. activation of CPT I C. glucagon/Insulin B. malonyl CoA D. activation of acetyl CoA carboxylase Murray, R.K., et. al., Harper's Illustrated Biochemistry, 27th ed., p.193 230. This disease results from the accumulation of phytanic acid in the brain and kidneys of patients: A. Tay- Sach’s disease C. Refsum’s disease B. Zellweger’s disease D. Niemann Pick’s disease Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 194. 231. Which is TRUE regarding apoproteins? A. Apo B 46 and B100 are synthesized in the liver. B. Apo A, B, C and D are peripheral apoproteins. C. Apo D is present exclusively in HDL. D. Apo A II and C III are stimulate endothelial lipoprotein lipase. Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., pp. 218. 232. The concentration of this lipoprotein is inversely related to the incidence of coronary artery disease: A. HDL1 C. HDL3 B. HDL2 D. pre β- HDL Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 222. 233. Which receptors are actively involved in reverse cholesterol transport? A. LDL C. LRP B. ABCA 1 D. SR- B1 Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 222. 28 234. The only part of an odd-chain fatty acid that is glucogenic is: A. acetyl CoA C. propionyl CoA B. butyryl CoA D. succinyl CoA Reference: Murray, R.K., et. al., Harper's Illustrated Biochemistry, 27 th ed., p.188 235. Which is the correct disease: enzyme deficiency pair? A. Fabry's disease: Ceramidase B. Gaucher's disease: Hexosaminidase A C. Niemann - Pick disease: Sphingomyelinase D. Tay-Sachs disease: - glucosidase Reference: Murray, R.K., et. al., Harper's Illustrated Biochemistry, 27th ed., p. 215 236. A patient with phenylketonuria has fair skin and eyes due to low levels of: A. biopterine C. tryptophan B. phenylalanine D. tyrosine Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 242. 237. The preferred amino acid as substrate for gluconeogensis is: A. alanine C. asparagine B. arginine D. aspartate Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 173 . 238. A patient with mental retardation and pigmentation of connective tissues has a deficiency of: A. alanine aminotransferase C. homogentisate oxidase B. aspartate aminotransferase D. phenylalanine hydroxylase Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 259. For questions 238-239, refer to the case below. D.D., a 2 week old male infant has failure to gain weight, nausea and vomiting after breast feeding. Blood examination revealed increased NH3+. If D.D. had ↑ blood level of argininosuccinate and friable hair, the deficient enzyme is: A. Argininosuccinate synthethase C. Carbamoyl P Synthetase 1 B. Argininosuccinate lyase D. Ornithine transcarbamoylase Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 252. 239. 240. The immediate treatment for D.D. is: A. antibiotics administration C. protein restriction B. hippurate administration D. IV fluids Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 251. 29 For questions 241-242, refer to the reaction below. NH3+ │ R1- C – COO- O ║ R2- C – COO- O ║ R1- C – COONH3+ │ R 2- C – COO- 241. This reaction requires which coenzyme? A. ATP C. NAD+ + B. FAD D. Vit. B6 Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 247. 242. The final products of this reaction are: A. alanine and pyruvate B. glutamate and α-ketoglutarate C. glutamate and oxaloacetate D. glutamine and oxaloacetate Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 248. 243. The reaction that helps maintain normal acid-base balance is: A. arginase C. glutamate dehydrogenase B. glutaminase D. glutamine synthetase Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 249. 244. GABA is an inhibitory neurotransmitter because it causes: A. ↑ Cl- efflux C. ↑ Cl- influx B. ↓↓Ca++ efflux D. ↓ K+ influx Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 274. 245. Which amino acid test dose administration is used to diagnose folate deficiency? A. cysteine C. lysine B. histidine D. tryptophan Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 254. 246. Which amino acid test dose administration is used to diagnose pyridoxal phosphate deficiency? A. histidine C. tryptophan B. leucine D. tyrosine Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 262. 247. To prevent obtaining a false-positive test for phenylketonuria, the screening should be done how many days after birth? A. immediately after birth C. 2 days B. one day D. 3 - 4 days Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 259. 30 A 10 year old boy with pellagra-like symptoms and a urine finding of ↑ amount of large neutral amino acids (aminoaciduria). What is the problem with this patient? A. homocystinuria C. glycinuria B. cystinuria D. Hartnup Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 262. 248. 249. One of the following statements about the THYROGLOBULIN is TRUE: A. It is the precursor of calcitonin B. It is iodinated, glycosylated carbohydrate with a molecular mass of 660 kilodalton C. It contains 115 tyrosine residues. D. It is initially synthesized in the apical portion of the cell Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 455. 250. One of the following events is TRUE of the concentration of IODIDE: A. It is an energy dependent process and is linked to the ATPase dependent Na-K pump. B. Thyroperoxidase is essential enzyme for the concentration of Iodide. C. It involves the iodination of the 3 position of the aromatic ring D. Phagocytosis and pinocytosis are essential in this process Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 456. 251. The half-life of T4 in blood is: A. 1.5 days C. 4.5 days B. 3.5 days D. 6.5 days Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 462. 252. One of the following statements about THYROID BINDING GLOBULIN is TRUE: A. Most of the T4 and T3 is in the unbound form. B. Thyroxine Binding prealbuminis quantitatively more important. C. Thyroxine binding globulin binds covalently nearly all thye T3 and T4 D. Estrogens increases the synthesis of thyroid Binding globulin. Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 462. 253. After exposing a jaundiced infant to phototherapy, the following is TRUE of bilirubin excretion: A. Bilirubin is converted to bilirubin diglucoronide. B. Phototherapy provides the sulfates needed to conjugate bilirubin. C. Bilirubin will be excreted in the feces as mesobilirubin. D. Increased amounts of urobilin are found in the urine. Reference: Murray, R.K., et. al., Harper's Illustrated Biochemistry, 26th ed., p. 280 Blood Coagulation 254. In normal patients, the fibrinolytic system of the coagulation system is have the following characteristized by: A. stabilization of the fibrin molecules by covalent cross-linkage bonding. B. glycoproteins that regulate coagulation mechanism. C. components which are thiol-dependent transglutaminases. D. glycoproteins that contain serine dependent active protease sites. Reference: Murray, R.K., et. al., Harper's Illustrated Biochemistry, 26th ed., p. 604 31 255. Intracellular calcium is mobilized in the cytoplasm by this PIP2-derived second messenger. A. Protein kinase C C. Inositol diphosphate B. Inositol triphosphate D. Phosphatidylinositol Reference: Murray, R.K., et. al., Harper's Illustrated Biochemistry, 25 th ed., p. 546 256. During the follicular phase of the menstrual cycle: A. there is a sudden increase of estradiol as the follicle enlarges B. there is proliferation of the endometrial lining C. the sudden drop in the levels of FSH heralds the end of follicular phase D. All of the above are TRUE Reference: Murray, R.K., et. al., Harper's Illustrated Biochemistry, 23rd Ed., p. 550 257. Which of the following statement/s is/are TRUE of estrogen? A. In, pregnancy, more estrone is coming from the placenta B. Estrogens are formed by the aromatization of androgens in a complex process that involves 2 hydroxylation steps C. As much as 50% of estradiol produced during pregnancy are produced by the ovaries D. All the statements are TRUE Reference: Murray, R.K., et. al., Harper's Illustrated Biochemistry, 23rd ed., p. 450 258. The following is TRUE about the luteal Phase of the menstrual cycle. A. There is follicular development B. The endometrial lining is thickened with the glands. C. There is low levels of estrogen. D. FSH and LH levels are high 259. A. B. C. Which statement/s is/are TRUE about mineralocorticoids? They are secreted from the zona fasciculata of the adrenal cortex The final step in the synthesis is conversion of an aldehyde to an alcohol Synthesis of mineralocorticoids depends on the presence of the enzyme 18- hydroxylase D. Mineralocorticoid comes from the parent compound Pregnenolone. Reference: Murray, R.K., et. al., Harper's Illustrated Biochemistry, 27 th ed., p. 446. 260. Which of the following is TRUE regarding the glycemic index? A. Foods with a low glycemic index cause less fluctuations in insulin secretion. B. Foods with a high glycemic index cause rapid fluctuations in insulin secretion C. Glucose and galactose have lower glycemic index than non-starch polysaccharides. D. Fructose and sugar alcohols are absorbed rapidly and have a higher glycemic index. Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 485. 261. This water-soluble vitamin requires a specific transport protein: A. Cobalamin C. Folic acid B. Thiamine D. Riboflavin Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 486. 32 262. Which of the following statements about factors affecting the basal metabolic rate is TRUE? A. The basal metabolic rate is higher in females due to greater adiposity B. Increase in body weight decreases the basal metabolic rate C. Basal metabolic rate decreases with advancing age D. Greater muscle tissue means a decrease in basal metabolic rate Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 491. 263. The form of Vitamin A involved in regulation of gene expression is: A. Retinol C. Retinyl phosphate B. Retinaldehyde D. Retinoic acid Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 492. 264. The main storage form of Vitamin D is: A. 7-dehydrocholesterol C. 25-hydroxycholecalciferol B. Cholecalciferol D. 1,25 –dihydroxycholecalciferol Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 500. 265. This vitamin participates in the transfer of 1-carbon methyl units: A. Folic acid C. Riboflavin B. Pantothenic acid D. Thiamine Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 500. 266. The following peptides arise from the proopiomelanocortin gene except: A. Melanocyte-stimulating hormone B. Corticotropin-like intermediate lobe peptide C. Adrenocorticotrophic hormone D. Gonadotropin releasing hormone Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 459. 267. Which of the following hormones is NOT a glycoprotein? A. Thyroid stimulating hormone B. Prolactin C. Follicle stimulating hormone D. Human chorionic gonadotropin Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 447. 268. Which of the following is the most utilized pathway of testosterone synthesis in the human testes? A. Dehydroepiandrosterone pathway B. Progesterone pathway C. Aromatase pathway D. 21-hydroxylase pathway Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 450. 269. Conversion of cholesterol to pregnenolone in the mitochondria of the testes is promoted by: A. Aromatase enzyme B. Follicle-stimulating hormone C. Adrenocorticotrophic hormone D. Luteinizing hormone Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 450. 33 270. Monosaccharides are characterized as: A. Carbohydrates that can be hydrolyzed to simpler carbohydrates. B. Are classified based on the number of carbon atoms. C. Are condensation products of simpler units. D. Occur in linear configuration. Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., Page 112 271. The glycemic index is a measure of: A. polarity C. solubility B. digestibility D. amphotericity Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., Page 116 272. The homopolymer structure of starch is called: A. dextrin C. glucosan B. amylopectin D. amylose Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., Page 116 273. The enzymic hydrolysis of starch by amylase produces: A. lactose C. lactulose B. maltose D. sucrose Page 112 274. The phosphorylation of glucose during glycolysis involves: A. an enzyme located in the mitochondrion B. GTP as the ATP donor C. A reversible reaction. D. an enzyme inhibited allosterically by the product Page 151 275. Which of the following is NOT a coenzyme of the pyruvate dehydrogenase complex? A. biotin C. coenzyme A B. lipoic acid D. pyridoxine Page 155 276. This enzyme of the Krebs Cycle catalyzes a substrate level phosphorylation reaction: A. isocitrate dehydrogenase C. citrate synthase B. malate dehydrogenase D. succinate thiokinase Page 146 Which is not a reaction that synthesizes purine nucleotides? A. synthesis form amphibolic intermediates B. phosphoribosylation of nucleobases C. ribosylation of purine nucleosides D. phosphorylation of purine nucleosides Page 301 277. 278. The multifunctional enzyme involved in the rate limiting reaction during pyrimidine synthesis includes: A. IMP dehydrogenase C. orotidylic decarboxylase B. dihydroorotase D. orotate phosphoribosyl transferase Page 307 34 279. Gout is a metabolic disorder caused by decreased activity of: A. hypoxanthine-guanine phosphoribosyltransferase B. adenosine deaminase C. glucose 6 – phosphatase D. xanthine oxidase Page 308 280. The endproducts of pyrimidine catabolism are: A. less water soluble than those of purine catabolism B. increased in patients with leukemia C. produced by adenosine deaminase D. increased with increased dietary intake of nucleotides Page 308 281. AcetylCoA derived from glycolysis is: A. reduced to water in the TCAC B. converted to NADPH in the hexose monophosphate shunt C. oxidized to CO2 and H2O in the TCAC D. converted by pyruvate dehydrogenase to form lactate Page 134 282. Which metabolic event occurs during the fed state? A. There is depletion of metabolic fuels. B. There is insulin-mediated uptake of glucose in the liver. C. Extracellular lipoprotein lipase is activated in reponse to insulin. D. Increased secretion of glucagons by the pancreas. Page 140 283. Muscle glycogen is not exported for utilization by peripheral tissues because of the absence of: A. gluokinase C. phosphofructokinse B. glycogen phosphorylase D. glucose 6 – phosphatase Page 142 284. Which metabolic fuel provides the energy during prolonged starvation? A. glucose C. amino acids B. ketone bodies D. lactate Page 143 285. The metabolic pathway that provides the fuel for erythrocytes is: A. β-oxidation C. anaerobic glycoslysis B. Tricarboxylci acid cycle D. ketogenesis Page 143 286. Which statement best describes RNA? A. The sugar moiety attached to the base is deoxyribose. B. The guanine content is equal to the cytosine content. C. RNA contains ribonucloetide uracil. D. RNA cannot be hydrolyzed by alkali. Page 314 287. The adapter molecule in translation is: A. mRNA B. tRNA C. rRNA D. snRNA Page 318 35 288. The human telomere sequence is described as: A. consisting of short repeat T-G rich sequences B. looped domains attached to the 3’ end of the chromosome C. binds sister chromatids during spindle formation D. involved with the aging when elongated Page 326 289. Which of the following features is NOT true of mitochondrial DNA? A. Encodes the 13 proteins involved in the respiratory chain B. AGA and AGG are stop codons. C. Contains 200,000 base pairs. D. Is circular and double stranded. Page 331 290. The synthesis of the forward strand during replication is described as: A. a continuous process moving from the 3’ to 5’ direction. B. producing short DNA fragments C. D. requiring an RNA primer for each short strand formed Page 336 291. Xeroderma pigmentosa results from ultraviolet damage to: A. the ORIC C. TG rich palindromes B. thymine dimers D. GATC sequence Page 345 292. The DNA starnd that is transcribed is referred to as the: A. coding starnd C. template strand B. nontemplate strand D. transcript strand Page 348 293. This RNA polymerase II is responsible for the synthesis of: A. rRNA C. tRNA B. mRNA D. snRNA Page 351 294. The rate of transcription may be enhanced by the following sequence elements, except: A. TATA box C. enhancers B. sigma factor D. silencers Page 355 295. In eukaryotes, the sequence that is translated to proteins is called: A. exons C. introns B. cistrons D. spliceosomes Page 359 296. 297. The enzyme that catalyzes the activation of amino acids is: A. peptidyl transferase C. aminoacyl-tRNA synthetase B. RNA polymerase D. methylguanosine synthase Page 367 Frameshift mutation results from: A. deletion of a triplet C. insertion of a nucleotide B. insertion of an amino acid D. deletion of an amino acid Page 370 36 298. The role of polyA tail during translation is observed during: A. elongation C. Termination B. initiation D. modification Page 372 299. Which antibiotic prevents binding of aminoacyl-tRNA to the A site? A. chloramphenicol C. tetracyclin B. puromycin D. rifampicin Page 378 300. DNA library that is composed of DNA copies from mRNA populations: A. chimeric library C. cDNA B. Colony D. genomic library Page 408 301. Insulin promotes glucose storage in the liver and muscles by: A. inhibition of PFK 2. B. stimulation of G-6-DH. C. activation of glycogen synthase. D. increased synthesis of F-2,6 bisP. Reference: Murray, R.K., et al., Harper’s Biochemistry, 27th Ed., p. 474. 302. A patient's DNA was analyzed for its chemical characteristics. It was found to have a high melting temperature which means that the DNA A. is rich in adenine-thymine base pairs B. is denatured at a higher temperature C. will exhibit hypochromicity at this temperature D. cannot undergo renaturation Harper's Biochemistry 27th edition, pp. 312-313 Application 303. A 20 year old male suffering from pneumonia was given a quinolone antibiotics by his physician. This antibiotics inhibits bacterial DNA topoisomerase. Which step in replication is inhibited by the quinolone? A. Unwinding of the double helix. B. Recognition of the origin of replication C. Formation of the RNA primer D. Elongation of the growing DNA polymer Harper's 27th edition, pp. 339 - 340 Application 304. A dermatologist advised her patient to avoid too much exposure to sunlight. Aside from sunburn, ultraviolet light causes what kind of damage to DNA? A. Insertion or deletion of nucleotide B. Oxidative free radical formation C. Formation of thymine-thymine dimer D. Cross-linkage between bases Harper's 27th edition, p. 343 Application 305. Cells cultured from patients with xeroderma pigmentosum exhibit low activity to which kind of DNA repair mechanism? A. Nucleotide excision-repair. B. Base excision repair. C. Mismatch repair D. double-strand break repair Harper's 27th edition, p. 345 Recall 37 306. Damage to the mitochondria may result in impaired mitochondrial DNA synthesis. In mammalian cells, this DNA is synthesized by which type of DNA polymerase? A. DNA polymerase alpha C. DNA polymerase delta B. DNA polymerase beta D. DNA polymerase gamma Harper's 27th edition, p. 336 Recall 307. Mammalian RNA polymerase II exhibit high sensitivity to the inhibitory effect of alpha-amanitin, a peptide toxin from a poisonous mushroom. Which of the following products will be decreased? A. ribosomal RNA C. messenger RNA B. transfer RNA D. small nuclear RNA Harper's 27th edition, p. 351 Application 308. Rifampicin, an anti-TB drug, inhibits DNA-dependent RNA polymerase. Which of the following steps of gene transcription will NOT be affected by the drug? A. Template binding C. Chain initiation B. Chain elongation D. Posttranscriptional modification Harper's 27th edition, p. 349 Application 309. A patient is taking steroid drug for his frequent attacks of asthma. Steroids have anti-inflammatory effects and also regulate gene expression. The effects of steroids are mediated by DNA elements found in which transcription control regions of the gene? A. Coding region C. Promoter proximal elements B. Distal regulatory elements D. CAAT and TATA boxes Harper's 27th edition, 354 - 356 Application 310. In beta thalassemia, the beta-globin gene is severely underexpressed resulting in diminished synthesis of the beta-chain of hemoglobin. This is a consequence of which posttranscriptional modification of primary RNA transcript? A. Faulty exon-intron splicing B. Addition of poly A tail in the 3' end C. Incorporation of 7-methylguanosine cap in the 5' end D. RNA editing in the coding region Harper's 27th edition, p.362 Application 311. The genetic code is affected by insertion or deletion of nucleotides in DNA resulting in frameshift mutation. Which characteristic of the genetic code is affected by this event? A. Universal C. Nonoverlapping B. Degenerate D. Unambiguous Harper's 27th edition, p.366, 370 - 371 Application 312. Chloramphenicol, a broad spectrum antibiotics, is known to inhibit peptidyltransferase during translation. What step in protein synthesis is affected by chloramphenicol? A. Formation of initiation complex. B. Elongation of the polypeptide chain. C. Termination of protein synthesis. D. Posttranslational modification Harper's 27th edition, p. 374 Recall 38 313. The elongation stage of protein synthesis is a multistep process which can be inhibited by antibiotics. What will happen when the translocation step is inhibited by streptomycin? A. Incoming aminoacyl-tRNA cannot bind to the A site B. Small ribosomal subunit is unable to dissociated from the large ribosomal subunit. C. No peptide bond synthesis can take place. D. Peptidyl-tRNA cannot shift from the A site to the P site. Harper's 27the edition, p. 375 Application 314. Some patients receiving methotrexate for treatment of cancer developed drug resistance. What could be the reason for these? A. Methotrexate induces amplification of genes for dihydrofolate reductase. B. The chemotherapeutic agent inhibits the transport of mRNA from nucleus to cytoplasm. C. The drug produces instability to the newly synthesized mRNA. D. It promoted the use of alternative transcription start site. Harper's 27th edition, p. 399 Application 315. Genomic technology oftentimes use probes. What can these molecules do? A. They allow visualization of specific DNA fragments. B. They are used to detect the presence of a specific fragment of DNA or RNA. C. They amplify specific DNA sequences. D. They are used to identify restriction sites. Harper's 27th edition pp. 409, 420 Recall 316. Oxygen toxicity can be attributed to the destructive effects of free radicals generated. These free radicals are removed by which of the following enzymes? A. NADPH-cytochrome P450 reductase C. Superoxide dismutase B. Peroxidase D. Catalase Harper's 27th edition, pp. 97 - 98 Recall 317. A suicide victim suffered from carbon monoxide poisoning when he was trapped in the garage with car engine running. Which component of the respiratory chain is inhibited by the poisonous gas? A. NADH dehydrogenase of Complex I B. Succinate dehydrogenase of Complex II C. Cytochrome c oxidoreductase of Complex III D. Cytochrome oxidase of Complex IV Harper's 27th edition, p. 107 Recall 318. People with bronchial asthma usually has hyperactive airway bronchoconstriction because of inflammation. Which of the following eicosanoid is responsible for this? A. leukotrienes C. thromboxanes B. prostaglandins D. prostacyclins Harper's 27th edition, p. 122 Application 319. A premature infant had respiratory distress syndrome after birth. Which of the following is a major constituent of the lung surfactant? A. distearoyl cephalin C. diarachidonyl plasmalogen B. dioleyl lipositol D. dipalmitoyl lecithin Harper's 27th edition, p. 125 Recall 39 320. Which of the following glycolipids is of considerable biologic interest because it serves as the receptor in human intestine for cholera toxin? A. sulfatide C. glucocerebroside B. ganglioside (GM3) D. globoside Harper's 27th edition, p. 126 Recall 321. Which of the following steroids although NOT derived from cholesterol acquire antirachitic property when irradiated with ultraviolet light? A. cholic acid C. ergosterol B. cholecalciferol D. corticosterone Harper's 27th edition, p. 127 Recall 322. Which of the following glycolipids is of considerable biologic interest because it serves as the receptor in human intestine for cholera toxin? A. sulfatide C. glucocerebroside B. ganglioside (G 323. How will carnitine deficiency affect the metabolism of glucose? A. It will lead to hypoglycemia. B. There is decreased synthesis of NADPH. C. It will promote glycogenesis D. There is increased synthesis of glucuronic acid Harper's 27th ed., p 187 - Application 324. A patient suffering from hypoalbuminemia will affect the transport of which lipid in the plasma? A. cholesterol C. unesterified fatty acid B. triacylglycerol D. phospholipid Harper's 27th ed., 187 - Application 325. Lack of carnitine in the mitochondria will directly and immediately affect which aspect of fatty acid oxidation? A. activation of fatty acid B. transport of fatty acid into the mitochondrial matrix C. oxidation of fatty acyl CoA D. formation of acetyl CoA Harper's 27th ed., 187 - Application 326. Infants born without peroxisomes will suffer from neurologic symptoms because of the accumulation of what type of fatty acid? A. short chain saturated fatty acid B. medium chain saturated fatty acid C. long chain saturated and unsaturated fatty acid D. very long chain unsaturated fatty acid Harper's 27th ed, p 194 - Recall 327. The basic form of ketosis occurs in starvation which involves depletion of carbohydrates coupled with increased: A. mobilization of free fatty acid B. fatty acid synthesis C. triacylglycerol synthesis D. cholesterol metabolism Harper's 27th ed., 194 - Application 40 328. A patient taking aspirin because of chronic arthritis will have decreased synthesis of which of the following? A. leukotrienes C. prostaglandin B. ketone bodies D. glycosphingolipid Harper's 27th ed., 196 - Application 329. Deficiency of biotin will result in decreased formation of which of the following? A. acyl carrier protein C. phosphatidic acid B. malonyl CoA D. ceramide Harper's 27th ed., 197 - Application 330. Essential fatty acid deficiency may be exacerbated by increased intake of which of the following foodstuffs? A. margarine C. coconut oil B. butter D. vegetable oil Harper's 27th ed., 203 - 204 - Application 331. Which of the following enzymes that degrade phosphoglycerides is one of the major toxins secreted by pathogenic bacteria? A. Phospholipase A1 C. Phospholipase A2 B. Phospholipase C D. Phospholipase D Harper's 27th ed., p. 212 - Recall 332. Enlarged liver and spleen, erosion of long bones, mental retardation in infants are seen in which of the following lysosomal storage diseases? A. Tay Sach's disease C. Gaucher's disease B. Fabry's disease D. Farber's disease Harper's 27th ed., 215 - Application 333. Patients with lipoprotein lipase deficiency will affect lipoprotein metabolism in what way? A. Increased formation of lipoprotein remnants B. Increased degradation of VLDL C. Decreased synthesis of HDL D. Decreased triglyceride hydrolysis in chylomicron Harper's 27th ed., 219 - 220 - Application 334. Administration of simvastatin will decrease the activity of which of the following enzymes involved in cholesterol synthesis? A. HMG-CoA synthase C. Squalene oxidocyclase B. HMG-CoA reductase D. Mevalonate kinase Harper's 27th ed., p 231 - Recall 335. During protein analysis a new amino acid was found which has a pK3 value, 3 units lower than that of cysteine. This so-called 21st amino acid is: A. aluminocysteine C. manganocysteine B. selenocysteine D. mangesimosysteine Harper's 27th ed., p. 14 - Recall 336. A protein isolated from a cancerous tissue absorbs visible light in the region of 280 nm. Which amino acid component of the protein is responsible for this? A. glycine C. valine B. arginine D. tryptophan Harper's 27th ed., p. 18 - Recall 41 337. Hemoglobin has the ability to neutralize protons released by carbonic acid. Which of the following amino acids is responsible for this? A. lysine C. histidine B. glutamine D. isoleucine Harper's 27th ed., p. 45 - Application 338. Proteins must be purified prior to analysis. Size exclusion chromatography separates proteins based on their Stokes radius which is a function of: A. molecular mass and shape B. solubility characteristics C. chemical interactions with other groups D. denaturation and renaturation potential Harper's 27th ed., p. 21 - 22 -- Application 339. Scurvy which is due to vitamin C deficiency results in the formation of defective collagen characterized by: A. decreased number of hydroxyproline and hydroxylysine B. increased in the number of covalent cross-links C. decreased synthesis of disulfide bridges D. increased interactions with copper and other minerals Harper's 27th ed., p 39 - Application 340. Tissue aminotransferases reversibly interconvert which of the following three amino acids and their corresponding alpha-keto acids? A. serine, threonine and tyrosine B. lysine, arginine and histidine C. glycine, alanine and isoleucine D. valine, leucine and isoleucine Harper's 27th ed., p. 243 - Application 341. Which of the following is NOT a part of the stages occuring in urea biosynthesis: A. transamination B. transaminidation C. oxidative deamination of glutamate D. ammonia transport Harper's 27th ed., 247 - Application 342. Deficiency of which of the following coenzymes will result in decreased transamination of amino acids? A. thiamine pyrophosphate C. pyridoxal phosphate B. biotin D. tetrahydrofolate Harper's 27th ed., 248 - Application 343. Transdeamination refers to the concerted reactions catalyzed by which of the following pair of enzymes? A. glutamate aminotransferase and glutamate dehydrogenase B. glutamate dehydrogenase and glutamine synthetase C. L-amino acid oxidase and cyseine desulfurase D. Serine dehydrase and glutamate transaminase Harper's 27th ed., 248 - Application 42 344. Of the six participating amino acids in urea synthesis which of the following functions solely as an enzyme activator? A. ornithine C. citrulline B. argininosuccinate D. N-acetylglutamate Harper's 27th ed., p. 249 - Recall 345. Ammonia intoxication impairs neuronal functions of the brain because it: A. impairs the synthesis of glutamine B. inhibits the activation of asparagine synthetase C. depletes the levels of alpha-ketoglutarate of the Kreb's cycle D. produces respiratory alkalosis Harper's 27th ed., p. 248 - Application 346. Which of the following chemical reactions typically initiates amino acid catabolism? A. glutamate dehydrogenation C. transmethylation B. transamination D. transulfuration Harper's 27th ed., p. 254 - Recall 347. Alkaptonuria, an inborn error of tyrosine metabolism, is characterized by darkening of the urine on exposure to air. This is due to oxidation of excreted: A. homogentisic acid C. maleylacetoacetate B. hydroxyphenylpyruvate D. fumarate Harper's 27th ed., p. 259 - Application 348. Maple syrup urine disease is a metabolic disorder of branched-chain amino acid catabolism. This is due to which of the following? A. lack of leucine, isoleucine and valine aminotransferase complex B. defective alpha-keto acid decarboxylase C. mutation of dihydrofolate reductase D. inability to attached the biotin coenzyme Harper's 27the ed., p. 265 - Application 349. S-adenosylmethionine is important in the body because it is involved in which of the following reactions? A. transulfuration C. methylation B. acetylation D. conjugation reaction Harper's 27th ed., p 274 - Recall 350. Which is a mechanism of oncogene activation? page 794 , MPL = 1 A. chromosome translocation C. promotion B. initiation D. proliferation 351. TRUE of oncogene activation of chronic myelogenous leukemia: page 794, MPL= .25 A. It involves gene re-arrangement of chromosome 9 and 14 B. The mutation results to fusion of BCR-ABL gene C. It is a recessive type of mutation D.It results to overexpression of c-myc. 352. Stage of chemical carcinogenesis which is genotoxic and irreversible: page 790, MPL= 1 A. initiation C. progression B. promotion D. mutation 43 353. Philadelphia chromosome in chronic myelogenous leukemia is due to: page 794, MPL= .5 A. gene rearrangement of chromosome 9 and 22 B. fusion of myc-ras C. activation of c-myc D. translocation of chromosome 8 and 14 354. Which of the following molecules function to transfer information from the nucleus to the cytoplasm? (page 309, MPL=1) A. DNA C. tRNA B. mRNA D. proteins 355. Three types of RNA involved in comprising the structural and functional core for protein synthesis, serving as a template for translation, and transporting amino acid, respectively, are: (Page 341, MPL=0.5) A. mRNA, tRNA, rRNA C. rRNA, tRNA, mRNA B. tRNA, mRNA, rRNA D. rRNA, mRNA ,tRNA 356. What is added to the 3'-end of many eukaryotic mRNAs after transcription? (Page 356, MPL=0.75) A. introns B. a poly A tail A C. a cap structure, consisting of a modified G nucleotide D. the trinucleotide 5'-CCA The regions of DNA in a eukaryotic gene that encode a polypeptide product are called: (Page 352, MPL=1) A. hnRNAs C. enhancers B. exons D. leader sequences 357. 358. A molecule containing sequences from two different species is known as a (Page 419, MPL = 1) A. clone B. cosmid C. plasmid D. chimeric molecule 359. The sequence of a gene that is transcribed but excised before translation: (Page 365, MPL = 1) A. enhancer B. exon C. intron D. repressor 360. Which of the following statements is FALSE regarding a genomic library? (Page 408, 409) MPL = 0.5 A. cDNA libraries are represented only by exons B. genomic DNA libraries are represented only by introns C. it is a collection of cloned fragments that represents the entire genome D. libraries are prepared by performing partial digestion of total DNA with a restriction enzyme 44 361. Which of the following statements is FALSE regarding the genetic code? (Page 366, MPL = 0.5) A. Some amino acids are encoded by several codons B. In general, the third nucleotide in a codon is less important than the first two in coding for a specific amino acid C. It is universal with the exception of tRNA molecules in mitochondria D. The reading of the genetic code may involve overlap of codons in some instances 362. The genetic code is said to have this property because multiple codons code for the same amino acid. (Page 366, MPL = 1) A. degenerate B. unambiguous C. universal D. no punctuation 363. POMC gives rise to all of the following substances, except: [p. 88] MPL- 1.0 A. ACTH B. endorphins C. α-MSH D. renin 364. Which of the following structural motifs is important for the transcriptional activation produced by some steroid-bound hormones? [pp. 393-396] MPL- 1.0 A. zinc fingers B. gly-x-y C. immunoglobulin folds D. EF hands 365. Irreversible activator of adenylyl cyclase causing ribosylation of the αstimulatory - subunit of the G-protein: [p. 567] MPL- 0.5 A. pertussis toxin B. phosphodiesterase C. cholera toxin D. calcium 366. Catecholamines undergo oxidative deamination by the action of the following enzyme: [25th ed., pp. 590-591] MPL – 0.5 A. tryptophan-5hydroxylase C. COMT B. MAO D. tyrosine hydroxylase 367. Estrogenic hormone which is predominant during pregnancy. [p. 450] MPL – 1.0 A. estradiol B. estriol C. estrone D. diethylstilbestrol 368. Leprechaunism is a rare condition characterized by elfin facies, low birth weight, decreased muscle mass and subcutaneous fat due to which of the following defects? [25th ed., pp. 622-623] MPL- 0.5 A. growth hormone deficiency B. thyroid hormone receptor defect C. growth hormone receptor defect D. insulin receptor defect 45 369. Growth hormone is synthesized and stored in large amounts in the anterior pituitary gland. Which of the following statements accurately describes GH? [25th e4d., pp. 551-553] MPL- 0.5 A. it is secreted continuously B. it stimulates cartilage and bone growth via somatomedin C C. it has a proinsulin-like effect in addition to its other actions D. synthesis is stimulated by the action of somatostatin 370. In congenital adrenal hyperplasia involving 21-hydroxylase deficiency, which of the following is true? [25th ed., p.587] MPL- 0.5 A. cortisol accumulates B. 17-OH-progesterone is an effective treatment C. most patients suffer "salt-wasting" due to lack of aldosterone D. levels of ACTH in blood decreased 371. Which of the following is a direct effect of parathyroid hormone in regulating calcium metabolism? [25th ed, p. 570] MPL – 0.5 A. increases bone resorption B. increases intestinal absorption of calcium C. decreases renal excretion of calcium D. decreases bone mineralization 372. The bond that links together complementary base pairs along DNA strands : A. hydrogen B. glycosidic C. phosphodiester D. peptide (Page 303, MPL = .5) 373. Poly A tail and 7 methyl guanosine cap are features of: A. DNA B. mRNA C. tRNA D. rRNA (Page 309, MPL = .5 ) 374. DNA synthesis occurs during this phase in the cell cycle : A. G1 C. G0 B. G2 D. S phase (Page 333, MPL = .5) 375. This drug blocks the reduction of dihydrofolate to tetrahydrofolate: A. allopurinol C. methotrexate B. colchicine D. sulfa drugs (Page 296, MPL= .5) 376. A blot transfer procedure for RNA analysis. (Page 409, MPL = 1) A. Southern blot C. Northern blot B. Western blot D. Southwestern blot 377. A manual enzymatic method of DNA sequencing. (Page 410, MPL = 0.5) A. Sanger’s method B. Restriction fragment length polymorphism C. Maxam-Gilbert method D. Polymerase chain reaction 46 378. This is a method of amplifying a target sequence of DNA. (Page 410, MPL =1 A. Flourescence in situ hybridization C. Sanger’s method B. Polymerase chain reaction D. Microarray technology 379. A two year old boy, SHORT for his age, presented with leg edema and abdominal swelling. He was weaned from breast milk at one year of age, because of the coming of another baby. He was fed rice or lugaw everyday mixed with condensed milk. The edema is caused by: A. Lack of protein in his diet B. Excessive intake of water C. Kidney failure D. Presence of intestinal parasites Recall Reference: Harper's Illustrated Biochemistry 27th ed., Murray, Granner & Rodwell 2006 The macgraw-Hill Companies, Inc., p. 241, par. 1, p. 487, par. 3 380. Catabolism of amino acids requires the participation of transaminase enzymes. What Coenzyme form of vitamin B is an important participant in this reaction? A. Thiamin pyrophosphate B. Nicotinamide adenine dinucleotide C. Tetrahydrofolic acid D. Pyridoxal phosphate Recall Reference: Harper's Illustrated Biochemistry 27th ed., p. 247 par. 2 , p. 498 - 499 381. In marasmus, the affected person has very little fat reserves and there is wasting of Muscles. The person is said to be in : A. Positive nitrogen balance B. Negative nitrogen balance C. Nitrogen balance D. Equilibrium Recall Reference: Harper's Illustrated Biochemistry 27th ed., p. 487 par. 3 382. Persons who consume large amounts of unleavened whole-wheat products may Experience calcium deficiency because: A. Wheat is poor in calcium B. Wheat contains phytic acid which prevents calcium absorption C. The wheat is deficient in vitamin D D. Absorbable form of calcium is not generated Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 485 par. 5 47 383. An elderly woman is believed to be suffering from vitamin B12 deficiency. Which of the Following can be the basis for this statement? A. She has been diagnosed to be deficient in cobalt B. She is a vegan C. She has methylmalonic aciduria D. Any of the above Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 499-500 384. The patient was in coma. Since diabetes was ruled out, how does one explain the condition? A. Patient has ammonia intoxication because of the liver pathology B. Coma is due to marked ketosis C. Acid-base balance of the patient is disturbed D. There is increase urea production Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 248 par. 4 385. The obese matron was instructed by her physician to alter her diet and eat only protein foods to bring down her weight. The matron was afraid however that the absence of carbohydrates in her meals will cause hypoglycemia and give her more problems. The physician was certain she does not have to worry about this because: A. She's going to cheat on her diet anyway B. The excess body fat will be converted to glucose C. Amino acids in excess are converted to glucose D. She has a lot of glycogen slores Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 172 par. 2, p. 175 summary, P. 269 summary 386. Deficiency of iron results in which of the following? A. Failure to metabolize proteins B. Heme-containing enzymes remain inactive C. There is liver dysfunction D. Individual goes into ATP production using fats Recall Reference: 387. Harper's Illustrated Biochemistry 27th ed., p. 504 Table An infant with genetic deficiency of glucose-6-phosphatase also known as von Gierke's disease will exhibit this clinical sign: A. Poor exercise tolerance B. Muscle dystrophy C. Hypoglycemia & lactic acidemia D. Glycogen with few branch points Recall Reference: Harper's Illustrated Biochemistry 27th ed., p. 166 Table 48 388. In the absence of creatine kinase enzymes, an athlete would have problem in: A. Oxidizing creatine B. Releasing ATP from biological oxidation C. Aerobic glucose oxidation D. Generating ATP reserves for muscle contraction Recall Reference: 389. Harper's Illustrated Biochemistry 27th ed., p. 583 par. 1-3 A young woman already in her fifth month of a carbohydrate and lipid-free diet was advised by her physician to increase the amount of fats in her diet because she appears to be suffering from vitamin A deficiency despite her regular vitamin intake. Which of the following complaints presented by the woman supports the diagnosis? A. She has lesions of the corner of the mouth B. Her wounds take longer time to heal C. She finds it hard to see in the dark when in a movie theater D. She has this sensation of "burning feet". Application Reference: Harper's Illustrated Biochemistry, 27th edition, p. 491, par. 4, line 3 390. Tests done on a two month-old baby showed deficiency in enzymes of the Uronic Acid Pathway. What clinical manifestation may be observed? A. Elevated urinary glucuronic acid B. Yellow coloration of the skin C. High direct-reacting bilirubin in plasma D. Accumulation of heme Application Reference: Harper's Illustrated Biochemistry, 27th edition, p. 289 par. 2, p. 290 par. 2 391. A 35 year old Muntinlupa inmate was confined to 6 weeks of isolation because of bad behavior. Although he was given regular meals, he stayed in the underground cell for the duration of the 6 weeks. If the prisoner became deficient in vitamin D because of this, what signs should the attending physician look for? In the inmate: A. There may be kidney stones formation B. The inmate may complain of tiredness C. He can easily be fractured D. Serum calcium will be extremely low Application Reference: Harper's Illustrated Biochemistry, 27th edition, p. 492 - 493 392. Thiamine deficiency can result in Wernicke- Korsakoff's syndrome. The absence of the vitamin prevents the conversion of pyruvate to acetyl coa on a high carbohydrate diet. Which compound would be found to be high in concentration in the plasma? A. Glucose B. Lactate & pyruvate C. Acetyl coa D. Alcohol 49 Application Reference: Harper's Illustrated Biochemistry, 27th edition, p. 496- 497 393. Important in the synthesis of collagen, this vitamin serves as cofactor of the mixed function oxygenase enzymes, proline & lysine hydroxylases: A. Vitamin B1 B. Vitamin B2 C. Vitamin C D. Folic acid Recall Reference: 9 394. Unlike other vitamins, niacin is a semi-essential vitamin because it can be synthesized from this amino acid: A. Proline B. Phenylalanine C. Tryptophan D. Histidine Recall Reference: 395. Harper's Illustrated Biochemistry 27th ed., p. 185 last par. A patient was tested for transketolase activity of the erythrocyte lysate. Results showed markedly low activity of the enzyme, consistent with the physicians impression of deficiency of this vitamin: A. Vitamin B2 B. Vitamin B3 C. Vitamin B5 D. Vitamin B1 Application Reference: 397. Harper's Illustrated Biochemistry 27th ed., p. 498, par. 1 Activity of the aldose reductase enzyme in the lens of the eye increases in the presence of high concentration of glucose. This initiates the conversion of glucose to a compound that has been linked to osmotic damage and cataract formation. What compound is this? A. Mannitol B. Galactitol C. Ribitol D. Sorbitol Recall Reference: 396. Harper's Illustrated Biochemistry 27th ed., p. 242 par. 3, line Harper's Illustrated Biochemistry 27th ed., p. 497, par. 1 Inorganic iron is best absorbed by the body in the ferrous form. What is the rationale behind the addition of vitamin C in many iron preparations? A. Vitamin C can take the place of iron B. Absorption of other minerals is prevented C. Vitamin C chelates iron D. Vitamin C keeps the iron in reduced (ferrous) state Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 485 - 486 50 398. In a routine medical check up, an executive showed elevated plasma levels of lactic acid dehydrogenase enzymes 1 & 2 and low levels of LDH 5. This prompted his physician to refer him to a cardiologist because: A. Low levels of LDH 5 indicated a clogged vessel B. It is part of the medical check up C. Increase levels of LDH 1 & 2 is indicative of myocardial infarction D. Angioplasty was needed Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 57 399. A tourist from the Caribbean fell ill and was diagnosed to have malaria. He was given primaquine upon admission to the hospital and was thought to be recuperating when he showed signs of hemolytic anemia. Tests showed he had glucose 6- phosphatase deficiency. What is the biochemical explanation for the hemolysis? A. The malarial parasite had invaded the rbc B. Inactivity of the Hexose Monophosphate Shunt prevented the NADPH - reduction of membrane glutathione C. The drug oxidized membrane proteins D. Absence of G6PD initiated release of peroxides Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 177 par. 2, p. 183 par. 2 A. Metabolic screening of a newborn showed absence of galactose uridyltransferase enzyme. What should be the dietary recommendation? A. Galactose should not be included in the diet B. Galactose - free and lactose -free milk should be given C. Newborn should be breastfed D. Liquid protein preparation instead of milk should be given Recall Reference: Harper's Illustrated Biochemistry 27th ed., p. 186 par. 2 400. A born-again vegetarian was diagnosed to be suffering from vitamin B12 deficiency. Which Of the following suggestions should be followed? A. The vegetarian should include meat in the diet B. He should be tested for pernicious anemia C. The born-again can take in vitamin B12 preparation to meet the requirement D. Intrinsic factor should be released from bonding Recall Reference: Harper's Illustrated Biochemistry 27th ed., p. 499 - 500 401. A woman had just given birth by ceasarean section. For fast recuperation she should be Advised to: A. Eat nutritious and protein-rich foods B. Rest in bed until the incision heals C. Include more carbohydrates in the diet D. Drink a lot of water 51 Recall Reference: Harper's Illustrated Biochemistry 27th ed., p. 487 - 488 Questions # 402-404 A 32 year old married woman consulted at the OPD because of increasing thirst and frequent urination. She is 5 feet 2 inches tall and weighs 168 lbs. 402. Which of the following statements best described the metabolic status in this patient? a. Her energy expenditure is greater than food intake hence she is diuresing b. She is obese and she has increased mortality c. The (BMR) basal metabolic rate of this patient is higher compared to a man of the same body weight d. She is frequently urinating because she has increased protein reserves Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 486 403. The BMI of the patient is: A. 25 B. 27 C. 29 D. 31 Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 486 par. 2 404. You want to give this patient a 1,500 cal/day diet because you want her to lose weight. How Do you formulate an appropriate plan for this patient? A. Carbohydrate - 55% Fats = 35% Protein = 10% B. Carbohydrate - 30% Fats = 20% Protein = 50% C. Carbohydrate - 0% Fats = 40% Protein = 60% D. Carbohydrate - 40% Fats = 40% Protein = 20% Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 132 405. The edema of a patient with kwashiorkor should respond best when prescribed with: A. Diet rich in protein B. Diuretics C. Bed rest D. Virgin coconut oil Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 487 52 406. A 32 year old physician suffered a 3rd degree burn. He stayed in the hospital for almost one month. What can be said of his metabolic condition A. The excretion of nitrogenous compounds is less than the dietary intake B. Negative nitrogen balance C. Positive nitrogen balance D. There is net retention of the nitrogen in the body as protein Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 487 407. The human body, even at rest, uses up energy. This amount of energy expenditure is termed as: A. Respiratory Quotient B. Basal Metabolic Rate C. Respiratory Burst D. Body Mass Index Recall Reference: 408. Harper's Illustrated Biochemistry 27th ed., p. 486 Uptake of glucose in these tissues is controlled by the hormone insulin: A. Liver & kidneys B. Adipose tissue & muscle C. Muscle & intestines D. Liver & rbc Recall Reference: Harper's Illustrated Biochemistry 27th ed., p. 140, par. 3, line 1 409. Between meals, the blood glucose concentration of the body is maintained through These metabolic pathways: A. Glycolysis & gluconeogenesis B. Glycogenesis & glycogenolysis C. Glycolysis & glycogenolysis D. Glycogenolysis & gluconeogenesis Recall Reference: Harper's Illustrated Biochemistry 27th ed., p. 134, par. 4, line 8 410. During continuous anaerobic physical activity, e.g. When working out in a gym, this metabolic pathway is used by the muscles A. Gluconeogenesis B. Glycolysis C. Hexose Monophosphate Shunt D. Glycogenesis Recall Ref. Harper's Illustrated Biochemistry 27th ed., p. 151, p. 158 53 411. When tested, a young woman, complaining of fatigability and poor exercise tolerance was found to have only one sixth the amount of carnitine found in others who had no muscle disease. This means that the above symptoms she is experiencing is due to: A. Inability of the body to synthesize lipids B. Inhibition of ATP production C. Failure of fatty acids to enter - oxidation D. Impairment of the mitochondria Recall Ref. Harper's Illustrated Biochemistry 27th ed., p. 187 par. 4 412. Newborn infants can generate more heat needed by the body because they contain Thermogenin, an uncoupling protein. This protein exerts its effect by: A. Increasing the amount of substrate oxidized B. Preventing heat loss C. Dissociating respiratory chain oxidation from ATP synthesis (phosphorylation) D. Activating respiratory chain enzymes Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 107, par. 4, p. 228 - 229 413. Erythrocytes are hemolyzed when there is impairment of the Pentose Phosphate Pathway and this is manifested in a person as hemolytic anemia. This defect is due to: A. Lack of NADPH from the Pentose Phosphate Pathway B. Non-synthesis of ATP C. Failure to release ribose D. Defect in the membrane transport Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 183- 184, par.1 414. A 30 year old patient was diagnosed to be suffering from a mitochondrial disease that specifically involves defect in mitochondrial energy transduction. Which of the following signs/symptoms will be evident? A. High body mass index (BMI), hyperactivity, increased appetite B. Hyperventilation, clammy sweat C. Muscle weakness, excessive perspiration, and elevated BMR (Basal metabolic Rate) D. Lack of appetite, hypoventilation Application Reference: 415. Harper's Illustrated Biochemistry 27th ed., p. 100, par. 2 A newborn infant tested positive in the phenylketonuria screening. The attending pediatrician ordered a change in the infant milk to one which contains negligible amount of: A. Lactose B. Proteins C. Fats D. Glucose 54 Application Reference: 416. Harper's Illustrated Biochemistry 27th ed., p. 259, par. 3 A drug used as an adjunct in the treatment of obesity inhibits pancreatic lipase. Following its intake, which of the following is expected to be excreted in great amount in the feces? A. Cholesterol B. Triacylglycerols C. Free fatty acids D. Bile salts Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 483, par. 4, p. 484 diagram 417. In the mucopolysaccharidoses, glycosaminoglycans are not degraded due to the absence of lysosomal hydrolases. Individuals suffering from this can be identified because of: A. Excessive accumulation and urinary excretion of the proteoglycans B. Presence of enzyme fragments in the urine C. Release of the core proteins in urine D. Increase turnover of affected cells Recall Reference: 418. Harper's Illustrated Biochemistry 27th ed., p. 555 par. 5 In the rare disease, analbuminemia, there is complete lack of serum albumin. The affected Individual presents with this: A. Extreme edema B. Edema & presence of free fatty acids C. Accumulation of triglycerides D. Elevated plasma cholesterol Recall Reference: Harper's Illustrated Biochemistry 27th ed., p. 592 par. 1, p. 187 par. 3 P. 711 Clinical Correlation , Textbook of Biochemistry, 5th ed., Thomas Devlin, Editors, 2002 Wiley-Liss 419. Metabolic screening was requested for a week-old newborn because the grandmother had noticed the dark stains on the wet diaper whenever she attended the infant. Tests identified the condition as alkaptonuria. What urinary metabolic should the physician request in the laboratory tests? A. Tryptophan B. Tyrosine C. Homogentisic acid D. Melanin Recall Reference: Harper's Illustrated Biochemistry 27th ed., p.259 par. 2 Textbook of Biochemistry, 5th ed., Thomas Devlin, p. 801, Clinical Correlation 55 420. Skeletal muscles do not have the enzyme glucose-6-phosphatase. This means: A. They cannot degrade glucose B. Glucose cannot be synthesized C. ATP cannot be generated D. Glycogen is stored in big amount Recall Reference: 421. L-xylulose reductase catalyzes the reduction of xylulose to xylitol. In affected individuals, Absence of this enzyme results in: A. Formation of cataracts B. Failure to synthesize nucleic acids C. Excretion of large amounts of urinary pentose D. Presence of skeletal deformities Recall Reference: 422. Harper's Illustrated Biochemistry 27th ed., p. 161, p. 167 Harper's Illustrated Biochemistry 27th ed., p. 184 par. 2 When there is restricted intake of carbohydrates as in starvation and uncontrolled diabetes mellitus, ketosis results because of: A. Change in ph of the body B. Failure to oxidize glucose C. Mobilization of fatty acids D. Inactivity of buffer systems Application Reference: Harper's Illustrated Biochemistry, 27th ed., p. 194 last par. , p.195 , 2nd par. (summary) 423. Measurement of hba1c or glycosylated hemoglobin provides valuable information for the management of diabetes mellitus because it: A. Is elevated in diabetes mellitus B. Reflects the mean glucose concentration over the preceding 6 - 8 weeks C. Is formed by reaction with hba D. Is released when rbc dies Application Reference: Harper's Illustrated Biochemistry 27th ed., p. 48, par.1 424. Inherited enzyme deficiencies of the Krebs-Henseleit cycle always present with this observation: A. Increase urea production B. Formation of organic metabolites C. Ammonia intoxication D. Depletion of citrulline Application Referenece: Harper's Illustrated Biochemistry 27th ed., p. 251, par. 4 56 425. The urine-soaked diaper of a week old baby was noted by the mother to smell like burnt sugar. Her concern turned into worry when the pediatrician told her the baby may be suffering from maple syrup urine disease. To confirm this, activity of the keto acid decarboxylase complex has to be measured. Which amino acids will have increased concentration in plasma and urine? A. Serine, threonine & hydroxyproline B. Cysteine, cystine, methionine C. Valine, leucine & isoleucine D. Glycine, alanine & asparagine Application Reference: 426. Harper's Illustrated Biochemistry 27th ed., p. 265, par. 2 Calcium deficiency manifestations may also be seen in people who consume: A. Large amounts of unleavened whole wheat products B. High concentrations of fatty acids C. High amounts of oxalates D. All of the above Application Referenece: Harper's Illustrated Biochemistry 27th ed., p. 265, par. 2 427. Milk intolerance, common among Asian populations and characterized by an osmotic type of diarrhrea following the intake of milk is attributed to deficiency of: A. Pancreatic amylase B. Lactase C. Sucrase D. Maltase Recall Ref. Harper's Illustrated Biochemistry 27th ed., 428. Rate-limiting reaction in cholesterol synthesis which is inhibited by the "statins" group of Drugs is catalyzed by this enzyme: A. Cholesterol esterase B. Squalene cyclase C. Mevalonate kinase D. Beta hydroxyl-beta methyl glutaryl coa reductase Recall Ref. Harper's Illustrated Biochemistry 27th ed., 429. p. 483, par. 1, line 3 p. 231, par. 2 All the carbon atoms of cholesterol are synthesized from this common metabolite: A. Alanine B. Acetyl coa C. Glucose D. Palmitate Recall Ref. Harper's Illustrated Biochemistry 27th ed., p. 230, par. 3 57 430. Carbohydrates, lipids & proteins can be oxidized to acetyl coa or specific metabolites intermediates using a final common pathway. The pathway functions in gluconeogenesis, lipogenesis and interconversion of amino acids. This pathway is known as: A. Glycolysis B. Hexose Monophosphate Shunt C. Citric Acid Cycle D. Glucuronic Acid Pathway Recall Ref. Harper's Illustrated Biochemistry 27th ed., p. 145, par. 1 431. In the capillaries, hemoglobin releases oxygen and accepts carbon dioxide. The process generates protons e which can then lower the blood ph. The buffering action of hemoglobin will prevent this from taking place. What amino acid residues in hemoglobin are most important in this shift in ph buffering effect at normal blood ph? A. Arginine B. Lysine C. Histidine D. Glutamate Recall Ref. Harper's Illustrated Biochemistry 27th ed., p. 43 432. The highest number of energy released as ATP is obtained by complete oxidation of this compound to carbon dioxide and water A. An amino acid B. A triglyceride C. Glucose D. A nucleic acid Application Ref. Harper's Illustrated Biochemistry 27th ed., p.189, par.1 433. p. 142, table 16-1, Laboratory tests done on a 3 year old boy showed excessive nucleic acid bases in the urine and negligible activity of hgprtase. Which statement explains the results obtained? A. Purine bases are very insoluble B. Low enzyme activity is due to feedback inhibition C. Salvage pathway of synthesizing nucleotides is inactive D. Young cells utilize the in vivo method for synthesis Application Ref. Harper's Illustrated Biochemistry 27th ed., p. 308, par. 1 434. In myocardial infarction where a major coronary artery is occluded, ischemia results and a lowered oxygen supply diminishes the amount of ATP available in the cell. This effect on cellular energy is due to: A. Release of enzymes B. Lack of oxygen which slows down the mitochondrial electron transport chain C. Inhibition of substrate level phosphorylation D. Kind of occlusion 58 Application Ref. Textbook of Biochemistry, 5th ed., Thomas Devlin, p. 591, Clinical Correlation 435. The patient was diagnosed to be suffering from megaloblastic anemia. Results of urinary tests showed 10 mg of formiminoglutamic acid (FIGLU), making the physician conclude that the patient has folic acid deficiency. Which statement explains the diagnosis given? A. Megaloblastic anemia is a unique feature of folic acid deficiency B. Transfer of formimino group of histidine to tetrahydrofolate does not take place and figlu is excreted C. Figlu is a metabolite of folate D. One carbon compounds are carried by folic acid Application Ref. Harper's Illustrated Biochemistry 27th ed., p. 254 par. 6 436. This is a correct statement regarding myoglobin: A. A monomeric protein B. Exhibits cooperativity C. A tetrameric protein D. Transports oxygen MPL= 0.5(page:40) 437. This is a correct statement regarding hemoglobin: A. Stores oxygen B. Exhibits cooperativity C. A stores CO2 D. A non-heme protein MPL = 0.5 page: 40 438. The globin chains in hemoglobin and myoglobin functions as/to: A. oxygen transporter B. Provides hindered environment for the heme iron C. inhibits allosteric modulators D. suit the proteins’ physiologic roles MPL= 0.5 page: 41 439. Allosteric properties of hemoglobin is a result if its: A. Primary structure B. Quarternary structure C. Tertiary structure D. Heme moiety MPL = 0.5 page 42 440. The color of heme is due to its: A. Conjugated ring structure B. Substituent side chains C. Cyclic Structure D. Iron group MPL = 1.0 p. 271 441. The key regulatory enzyme in heme biosynthesis is: A. ALA dehydratase B. ALA synthase C. Heme oxygenase D. UDP-glucuronyltransferase 59 MPL =0.5 p. 272 442. Sugar with glycemic index less than 1: A. Glucose B. Fructose C. Galactose D. Lactose MPL = 1.0 p. 474 443. Foods with low glycemic index: A. cause less fluctuation in insulin secretion B. Not ideal in treating diabetes mellitus C. examples are starch D. Glucose have glycemic index more than 1 MPL = 0.5 p. 474 444. Enzyme that catalyzes hydrolysis of starch: A. Lipase B. Amylase C. protease D. HCL MPL = 1.0 p. 474 445. Clinical manifestation of lactose intolerance is due to: A. Lactose presence in the large intestines B. Bacterial fermentation of glucose C. Bacterial fermentation of galactose D. Lactase oversecretion of the small intestines MPL = 0.25 p. 475 446. A sugar that is absorbed in the small intestine by active transport: A. Maltose B. Glucose C. Fructose D. Lactose MPL = 1.0 447. This is the process of forming glucose from noncarbohydrate precursors like lactate, amino acids and glycerol: A. glycolysis B. gluconeogenesis C. glycogenesis D. cori cycle MPL= 0.5 p. 133 448. Muscles glycogen cannot contribute directly to plasma glucose because it lacks this enzyme: A. Glucose-6-phosphate dehydrogenase B. Phosphoglucomutase C. Glucose-6-phosphatase D. Glucokinase MPL=0.75 p. 142 60 449. Nearly all products of digestion of carbohydrates, fats and proteins are metabolized to what common metabolite? A. Acetyl CoA B. pyruvate C. Glucose-6-phosphate D. lactate MPL=0.5 144 450. It is referred to as the final common pathway for the oxidation of carbohydrates, lipids and proteins: A. Embden-Meyerhof pathway B. Hexose monophosphate shunt C. Glucuronic acid pathway D. Citric acid cycle MPL=1.0 p. 145 451. These two amino acids yield only Acetyl CoA on oxidation, and hence cannot be used for gluconeogenesis: A. Glycine and Lysine B. Lysine and leucine C. Valine and Leucine D. Proline and Glycine MPL=0.5 p. 139 452. Interconversion of Glycine and Serine requires what coenzyme? A. Niacin B. Riboflavin C. Pyridoxine D. Folic acid MPL=1.0 p. 257 453. A major role of this vitamin is in the control of cell differentiation and turnover: A. Vit A B. Vit C C. Vit E D. Vit D MPL=0.75 p. 491 454. This is the earliest sign of Vit A deficiency: A. Inability to adapt to dim light B. loss of sensitivity to green light C. keratomalacia D. keratinization of the lining of epithelial cells MPL=0.5 p. 491 455. What is the most important function of lipid in the adipose tissue and around internal organs? A. as electrical insulator B. as thermal insulator C. as source of energy D. for lipid transport MPL:75% p. 121 61 456. Which among the following is a complex lipid composed of fatty acid and shingosine and carbohydrate? A. fats B. oil C. phospholipids D. glycolipids MPL:50% p. 121 457. Which eicosanoids promotes bronchoconstriction and play a part in asthma? A. prostaglandins B. leukotienes C. Thromboxanes D. Prostacyclin MPL:50% p. 122 458. What is the process involved in the manufacture of margarine? A. Hydrogenation B. Hydroxylation C. Dehydrogenation D. Oxidation MPL:50% p. 123 459. Which is considered as transcriptionally active chromatin A. euchromatin B. heterochromatin C. constitutive chromatin D. telomerase MPL:75% p. 324 460. This is the noncoding intervening sequence A. exon B. intron C. kinetochore D. telomerase MPL:75% p. 324 461. This is the enzyme responsible DNA unwinding during replication A. DNA ligase B. Helicase C. DNA polymerase D. Topoisomerase MPL:75% p. 336 462. Eukaryotic RNA polymerase II synthesizes: A. rRNA B. mRNA C. tRNA D. snRNA MPL:25% p. 351 463. What is the key tool in recombinant DNA research? A. taq polymerase B. restriction enzymes C. Deoxyribonuclease D. Primase MPL:50% p. 403 62 464. The total DNA of a cell or tissue. A. Genomic DNA library B. cDNA library C. introns D. exons MPL:50% p. 408 465. Immunoglobulin are mostly synthesized in the: A. T-helper cell B. Natural killer cells C. Plasma cells D. macrophages MPL:1.0 p. 599 466. Not true of an immunoglobulin: A. it is made up of 2 L chains and 2 H chains B. it has a Y or T shape C. it has 4 variable regions D. it has 2 constant regions in its entire structure MPL:0.25 pp. 599-600 467. True of the variable region of an immunoglobulins: A. it is located at the middle most part of the light and heavy chains B. it is where the CDRs (complementary determining regions) are located C. may form two or three antibodies which are identical to each other. D. there are no hypervariable regions. MPL:0.25 p. 601 468. The part of the antibody that binds to the antigen: A. Fa,b B. The antigen determinant site C. The N-terminal of both the light and the heavy chain D. The hypervariable regions of both the L and H chains MPL:0.5 p. 601 469. The part of the antigen that binds to the antibody: A. Fa,b B. The antigen determinant site C. The N-terminal of both the light and the heavy chain D. The hypervariable regions of both the L and H chains MPL:0.5 p. 601 470. A transcription factor involved in the stimulation of acute phase proteins synthesis, is nuclear factor __________, A. Gamma-B B. Kappa-B C. Alpha-B D. Omega-B MPL:0.25 p. 591 63 471. The C-reactive protein is so called as such, because it binds with the _________, of Pnuemococci, haptoglobin, α, acid glycoproteises: A. C-monomers B. C-dimers C. C-polypeptides D. C-polysaccharides MPL:0.25 p. 590 472. The proteins that stores iron in the cells, is: A. hemosiderin B. hemochromatine C. ferritin D. . transferring MPL:0.25 p. 594 473. The most potent activator of platelet aggregation in thrombus formation is: A. Collagen B. TXA C. ADP D. fibrinogen MPL:0.25 p.; 609 474. A type of thrombus that is formed in arteries is: A. disseminated fibrin deposits B. white thrombus C. red thrombus D. yellow thrombus MPL:1.0 p. 606 475. The chief constituent of fibrous part of plants, is: A. Starch B. Cellulose C. Chitin D. Peptidoglycan MPL:1.0 p. 116 Which of the following carbohydrates do not have a structural functions? A. Cellulose B. Mucin C. Chitin D. Peptidoglycan MPL:0.25 p. 119 476. The de novo pathway of purine biosynthesis utilized______ATPs: A. 7 B. 8 C. 6 D. 5 MPL:0.5 p. 305 477. The ultimate hydrogen donor in deoxyribonucleotides formation is: A. thioredoxin B. NADPH C. dihydrofolate D. NADH MPL:0.5 p. 306 64 478. Which of the following coenzymes is involved in electron transfer? A. NAD B. biotin C. pyridoxal phosphate D. tetrahydrofolic acid MPL:0.5 p. 49 479. Which of the following statements about noncompetitive inhibitor is true? A. it is a structural analog of the normal substrate B. it binds to the active site of enzyme C. Km is not change but Vmax is decreased D. It can be reversed by adding more substrate MPL:0.25 p. 68 480. Enzymes that are activated through covalent modification usually involved 75 phosphorylation of this amino acid residue in the active site. A. phenylalanine B. tryptophan C. lysine D. serine MPL:0.5 p. 75 481. Carbon monoxide from vehicle exhaust inhibit mitochondrial ATP production by, A. decreasing overall potential of the electron transport chain B. uncoupling oxidative phosphorylation C. disturbing proton gradient across intermembranous space and matrix D. binding to cytochrome oxidase 482. Oxidation is the, A. loss of electrons B. gain of electron C. gain of protons D. digestion of energy foods 483. The final electron acceptor is, A. carbon dioxide B. oxygen C. water D. hydrogen 484. Which of the following is responsible for the polarity of a strand of nucleic acid? A. acid B. base C. sugar D. phosphate 485. Nucleic acids are polymeric macromolecules composed of units of, A. nitrogenous bases B. nucleotides C. negatively charge phosphates D. nucleosomes 65 486. What is the bond that links nucleotides together to form a strand of nucleic acid? A. glycosidic bond B. phosphodiester bond C. phosphoester bond D. hydrogen bond 487. Which vitamin in the diet is required for de novo pathway of adenosine monophosphate synthesis and whose deficiency may lead to purine deficiency, a rare disease in humans? A. folic acid B. nicotinic acid C. pantothenic acid D. vitamin C 488. Which of the following organs/tissues is capable of de novo purine biosynthesis? A. brain B. erythrocytes C. polymorphonuclear leukocytes D. liver 489. The lipooxygenase pathway synthesizes: A. Prostaglandins B. Leukotrienes C. Thromboxanes D. Lipid peroxides 490. Ketone bodies are oxidized for ATP generation via: A. Beta-oxidation pathway B. Cyclooxygenase pathway C. Lipoxygenase pathway D. Kreb’s citric acid cycle 491. Glycerol phosphate, the backbone of TAG, is synthesized in adipose tissue by: A. phosphorylation of glycerol by glycerol kinase B. phosphorylation of diacylglycerol C. reduction of dihydroxyacetone phosphate D. glycerol dehydrogenase 492. Which of the following is not true of the beta-oxidation of palmitic acid? A. occurs in the matrix of mitochondria B. two oxidation steps generate 5 mols of ATP per cycle C. cleavage reaction occurs between the beta and gamma carbons D. the cell conserves 129 moles ATP per mole of palmitic acid 493. Glycolysis, glycogenesis and lipogenesis are stimulated by this hormone: A. glucagons B. cortisol C. insulin D. epinephrine 66 494. This hormone is synthesized and released immediately in its final form: A. aldosterone B. insulin C. T3 D. DHT MPL:1.0 495. Hormone derived from cholesterol A. TSH B. 1,25(OH)2-D3 C. Tyroxine D. GH MPL:1.0 p. 447 496. Which sugar derivatives polymerize to form structural polysaccharide?: A. Sugar phosphate and sugar acid B. Sugaramino acid and sugar sulfate C. Sugar acid and sugar sulfate D. Sugar amino and sugar acid 497. Digestability of sugar depends on the presence of this glycosidic linkage: A. Alpha B. Beta C. Gamma D. Theta 498. Which of the following disaccharides is best suited to provide the structural sugars?: A. Sucrose B. Lactose C. Mannose D. Cellubiose 499. Which of the following is a saturated fatty acid?: A. Oleic B. Linoleic C. Arachidonic D. Palmitic 500. Which of the following is a phospholipid?: A. Ceramide B. Cholesterol C. Cephalin D. Corticosteroid Which of the following is a fatty acid?: A. Succinic acid B. Prostanoic acid C. Glutamic acid D. Butyric acid 501. Which of the following backbone will make the lipid saponifiable ?: A. Isoprene nucleus B. Steroid nucleus C. Sphingosine D. Prostanoic acid 67 502. The presence of which fatty acid will make the membrane more fluid: A. Myristic B. Palmitic C. Stearic D. Lignoceric 503. Which of the following lipids will stabilize membrane?: A. Cardiolipin B. Cortisol C. Cholesterol D. Ceramide 504. Which of these is an essential amino acid?: A. Serine B. Tyrosine C. Isoleucine D. Glutamine 505. The simplest amino acid is: A. Cysteine B. Glycine C. Serine D. Valine 506. An example of an aromatic amino acid is: A. Serine B. Aspartic C. Glutamic D. Tryptophan 507. A protein exposed to denaturing agent becomes: A. Antigenic B. Inert C. Undigestible D. Reactive 508. The linkage between the nucleotides: A. Glycosidic B. Peptide C. Methene D. Phosphodiester 509. An important bond in base pairing: A. Covalent B. Glycosidic C. Hydrogen D. Phosphodiester 510. DNA strands that show high melting temperature contains: A. High carbohydrate residues B. High histone content C. High G-C pairs D. High supercoiling 68 511. Which purine analogue is useful in cancer chemotherapy?: A. Propyl thiuracil B. 1,3,7 trimethylxanthine C. 6 mercaptopurine D. 4 hydroxypyrazolopyramidine 512. Which vitamin is a purine derivative?: A. Cyanocobalamine B. Inositol C. Carotene D. Niacin 513. Enzyme that hydrolyzes glycogen: A. Hexokinase B. Phosphorylase C. Aconitase D. Transketolase 514. A metabolic intermediate leading to glycogenesis, pentose phosphate pathway and glycolysis: A. Acetyl CoA B. Citric acid C. Glucose 6 phosphate D. Pyruvate 515. This metabolite when transaminated leads to sugar amine pathway: A. Fructose 6 phosphate B. Glyceraldehyde 3 phosphate C. Glucose 1 phosphate D. Ribose 5 phosphate 516. This metabolite leads to the production of NAD in Embden Meyerhoff pathway: A. Acetyl CoA B. Glyceraldehyde 3 phosphate C. Lactic acid D. Pyruvate 517. This pathway sustains the energy requirement of mature RBC. A. Kreb’s cycle B. Pentose phosphate C. Glycolysis D. Anaplerotic 518. This pathway provides NADPH for lipogenesis A. Kreb’s cycle B. Phosphogluconic C. Uronic D. Cori 519. In the intestinal mucosal cells, triglyceride is: A. Hydrolyzed B. Esterified C. Synthesized D. Absorbed 69 520. Lipolysis will be formed with increased levels of this hormone: A. Insulin B. Epinephrine C. Cortisol D. Esatrogen 521. In beta oxidation, for every break of an ester bond (saturated) this much amount of ATP is generated: A. 23 B. 3 C. 5 D. 12 522. In fasting and starvation the level of these metabolites are increased: A. Oxysteroid B. Ketone bodies C. Thyroxine D. Insulin 523. Arachidonic acid deficiency usually do not occur because of this enzyme: A. Polymerase B. Kinase C. Desaturase D. Ligase 524. Amino acids are transported intracellularly using this cycle: A. Kreb’s cycle B. Kreb’s – hanseleit cycle C. Cori cycle D. Gamma glutamyl cycle 525. The major product of nitrogen catabolism in humans is: A. Uric acid B. Creatinine C. Urea D. Ammonia 526. What urinary metabolite is useful in the assessment catecholamine induced hypertension?: A. Hydroxyindole acetic acid B. Phenylpyruvic acid C. Vanillyl mandylic acid D. Paraamino hippuric acid 527. The starting materials for porphyrin biosynthesis are: A. Acetyl CoA and serine B. Malonyl CoA and glutamine C. Succinyl CoA and glycine D. Amino acyl and methionine 528. Which of these is the key regulatory enzyme in heme biosynthesis?: A. Ferrochelatase B. ALA synthase C. Pyrollase D. Uroporphyrin decarboxylase 70 529. What is this organic acid that is used to conjugate bilirubin?: A. Propionic acid B. Glucuronic C. Acetic acid D. Butyric acid 530. Which of these enzyme deficiency produces abdominal pain with out skin manifestation?: A. Coproporphyrinogen oxidase B. Uroporphyrin synthase C. Ferrochelatase D. Pyrollase 531. Activity exhibited by enzymes when fully saturated: A. Km B. Vmax C. ½ Vmax D. Vo 532. CPK elevation is suggestive of: A. Hepatitis B. Cardiomyopathy C. Pancreatitis D. Bone tumor 533. Pyruvate kinase deficiency produces: A. Hypoglycemia B. Hemolytic anemia C. Hypercholesterolemia D. Mal absorption 534. Which of these is a pyrimidine excretory metabolite?: A. Ammonia B. Urea C. Uric acid D. Allantoin 535. Which of these enzymes is important in DNA sequencing? A. B. C. D. 536. Ligase Polymerase Exonuclease Kinase A very anxious student hyperventilates an hour before the biochemistry board exam. What is the effect of hyperventilation on his Pco 2 and blood pH? A. Pco2 decreases and pH increases. B. Pco2 decreases and pH decreases. C. Pco2 increases and pH decreases. D. Pco2 increases and pH increases. Ans. A Ref: Harper’s Biochemistry 24th ed. Pp. 18-19 MPL: 0.25 71 537. A protein rich in which of the following amino acids will provide the greatest buffering capacity at physiologic pH? A. Valine B. Aspartic acid C. Lysine D. Histidine Ans. D Ref: Harper’s Biochemistry 24th ed. p.26 MPL: 0.75 538. Which of the following laboratory results would best indicate metabolic alkalosis? A. Increased Pco2, increased pH, increased HCO3. B. Normal Pco2, increased pH, decreased HCO3. C. Increased Pco2, increased pH, normal HCO3. D. Decreased Pco2, increased pH, normal HCO3. Ans. A Ref: Harper’s Biochemistry 24th ed. p.304 MPL: 0.75 539. What is the property of water that will contribute the most to its ability to dissolve compounds? A. Very few interactive forces in its structure. B. Hydrogen bond formation between water and long-chain fatty acids. C. Covalent bond formation between salt and water. D. Hydrogen bond formation between water and biochemical molecules. Ans. D Ref: Harper’s Biochemistry 24th ed. p.15-17 MPL: 0.75 540. A 3-year old child is diagnosed to have Hurler’s syndrome. The diagnosis of Hurler’s syndrome is MOST efficiently made by analyzing the patient’s DNA for: A. A region of DNA that does not encode RNA. B. Alternative forms of the L-Iduronidase gene. C. The entire set of genes in one leukocyte. D. A nucleotide substitution in the L-Iduronidase gene. Ans. B Ref: Harper’s Biochemistry 24th ed. p. 678 MPL: 0.25 541. Which of the following statements regarding a double-helical molecule of DNA is TRUE? A. All hydroxyl groups of pentoses are involved in linkages. B. Bases are perpendicular to the axis. C. Each strand is identical. D. Each strand replicates itself. Ans. B Ref: Harper’s Biochemistry 24th ed. p.386 MPL: 0.75 72 542. A newborn baby has a sibling with sickle cell anemia and is at risk for this disease. The appropriate diagnostic test for sickle cell anemia in this baby would include which of the following? A. DNA amplification B. Hemoglobin antibodies C. Red cell counting D. DNA fingerprinting Ans. A Ref: Harper’s Biochemistry 24th ed. p. 468 MPL: 0.25 543. Which of the following would BEST describe polymorphism? A. One phenotype, multiple genotypes B. Non-random allele association C. One locus, multiple abnormal alleles D. One locus, multiple normal alleles Ans. D Ref: Harper’s Biochemistry 24th ed. p. 476 MPL: 0.25 544. What is that process that occurs at the 5-position of Cytidine and is often correlated with gene inactivation? A. Gene conversion B. Sister chromatid exchange C. Gene rearrangement D. DNA methylation Ans. D Ref: Harper’s Biochemistry 24th ed. p.466 MPL: 0.75 545. Restriction Fragment Length Polymorphism (RFLP) analysis can only be used to follow the inheritance of a genetic disease if: A. The disease-causing mutation is at or closely linked to an altered restriction site. B. Proteins of mutated and normal genes migrate differently upon gel electrophoresis. C. Mutations are outside restriction sites so that cleaving still occurs. D. mRNA probes are used in combination with antibodies. Ans. A Ref: Harper’s Biochemistry 24th ed. p. 478 MPL: 0.25 546. The chromosomes of mammalian cells are 20 times as large as those of Escherichia coli. How can replication of mammalian chromosomes be carried out in just a few minutes? A. The higher temperature of mammalian cells allows for an exponentially higher replication rate. B. Hundreds of replication forks work simultaneously on each piece of chromosomal DNA. C. Many RNA polymerases carry out replication simultaneously on chromosomal DNA. D. The presence of histones speeds up the rate of chromosomal DNA replication. 73 Ans. B Ref: Harper’s Biochemistry 24th ed. p. 407 MPL: 0.75 547. Following ultraviolet damage to DNA in the skin, which of the following is MOST likely to occur? A. A specific nuclease detects damaged areas. B. Purine dimmers are formed. C. Both strands are cleaved. D. Endonuclease removes the damaged strand. Ref: Harper’s Biochemistry 24th ed. p. 814 MPL: 0.75 548. Which of the following statements about the genetic code is the MOST accurate? A. Information is stored as sets of dinucleotide repeats called codons. B. The code is degenerate. C. There are 64 codons, all of which code for amino acids. D. Information is stored as sets of trinucleotide repeats called codons. Ref: Harper’s Biochemistry 24th ed. p. 433-434 MPL: 0.75 549. Which of the following is provided by the Northern Blot Analysis? A. Detection of specific base pairs. B. Detection of DNA molecules. C. Detection of RNA molecules. D. Detection of proteins. Ref: Harper’s Biochemistry 24th ed. p. 472-473 MPL: 1.0 550. In contrast to DNA polymerase, RNA polymerase: A. Fills in the gap between the Okazaki fragments. B. Works only in a 5’ to 3’ direction. C. Edits as it synthesizes. D. Synthesizes RNA primer to initiate DNA synthesis. Ref: Harper’s Biochemistry 24th ed. p. 418 MPL: 0.75 551. What is the function of a promoter site on DNA? A. Transcribes repressor B. Initiates transcription C. Codes for RNA polymerase D. Regulates termination Ref: Harper’s Biochemistry 24th ed. p. 420 MPL: 1.0 74 552. 553. The consensus sequence 5’-TATAAAA-3’ found ineukaryotic genes is almost similar to a consensus sequence observed in prokaryotes. The consensus sequence is important as the: A. Only site of binding of RNA polymerase II. B. Promoter site for all RNA polymerases. C. Termination site for RNA polymerase II. D. First site of binding of a transcription factor for RNA polymerase II. Ref: Harper’s Biochemistry 24th ed. pp. 421-422 MPL: 0.75 The so-called “caps” of RNA molecules: A. Allow tRNA to be processed. B. Occur at the 3’-end of tRNA. C. Are composed of poly A. D. Are unique to eukaryotic mRNA. Ref: Harper’s Biochemistry 24th ed. p. 428 MPL: 1.0 554. In bacterial RNA synthesis, what is the function of the “rho” factor? A. It binds catabolite repressor to the promoter region. B. It increases the rate of RNA synthesis. C. It eliminates the binding of RNA polymerase to the promoter. D. It participates in the proper termination of transcription. Ref: Harper’s Biochemistry 24th ed. p. 419 MPL: 1.0 555. Which of the following statements correctly describes the nucleolus of a mammalian cell? A. It differs from that found in bacterial cells in that histones are present. B. It may contain hundreds of copies of genes for different types of ribosomal RNAs. C. It synthesizes 5S rRNA. D. It synthesizes all ribosomal RNA primary transcripts. Ref; Harper’s Biochemistry 24th ed. p. 428 MPL: 0.75 556. Which of the following statements correctly describes the synthesis of mammalian mRNA? A. Each mRNA often encodes several different proteins. B. Several different genes may produce identical mRNA molecules. C. Mammalian mRNA undergoes minimal modification during its maturation. D. The RNA sequence transcribed from a gene is identical to the mRNA that exits from nucleus to cytoplasm. Ref: Harper’s Biochemistry 24th ed. p. 427 MPL: 0.75 75 557. Certain amino acids are not part of the primary structure of proteins but are modified after translation. In scurvy, which amino acid that is normally part of collagen is not synthesized? A. Hydroxytryptophan B. Hydroxytyrosine C. Hydroxyhistidine D. Hydroxyproline Ref: Harper’s Biochemistry 24th ed. pp. 668-669 MPL: 1,0 558. Immunoglobulin G (IgG) molecules can be characterized by which of the following statements? A. They are maintained at a constant level in the serum. B. They contain nucleic acids. C. They contain mostly carbohydrates. D. They can be separated into subunits with a reducing agent and urea. Ref: Harper’s Biochemistry 24th ed. p.716 MPL: 1.0 559. Which of the following proteolytic enzymes is activated by acid hydrolysis of the proenzyme form? A. Trypsin B. Elastase C. Pepsin D. Carboxypeptidase Ref: Harper’s Biochemistry 24th ed. p.636 MPL: 1.0 560. Which of the following amino acids is ionizable in proteins? A. Leucine B. Histidine C. Valine D. Alanine Ref: Harper’s Biochemistry 24th ed. p. 294 MPL: 0.75 561. The oxygen carrier of muscle is the globular protein myoglobin. Which of the following amino acids is highly likely to be localized within the interior of the molecule? A. Arginine B. Aspartic acid C. Glutamic acid D. Valine Ref: Harper’s Biochemistry 24th ed. p.53 MPL: 0.75 76 562. Which of the following statements concerning immunoglobulins is most accurate? A. IgE is the principal antibody in the serum. B. The heavy chains are similar in each class of immunoglobulin. C. The constant regions of the heavy chains are the same in each class of immunoglobulin. D. IgE is the major immunoglobulin found in external secretions. Ref: Harper’s Biochemistry 24th ed. p.718 MPL: 1.0 563. Under normal conditions in the blood, which of the following amino acid residues of albumin is neutral? A. Arginine B. Aspartate C. Glutamine D. Histidine Ref: Harper’s Biochemistry 24th ed. p. 294 MPL: 0.75 564. Which of the following carbohydrates would be most abundant in a diet of strict vegetarians? A. Amylose B. Lactose C. Cellulose D. Glycogen Ref: Harper’s Biochemistry 24th ed. p. 141 MPL: 1.0 565. The major metabolic product under normal circumstances by erythrocytes and by muscle cells during intense exercise is recycled through the liver in the Cori cycle. The metabolite is: A. Oxaloacetate B. Glycerol C. Alanine D. Lactate Ref: Harper’s Biochemistry 24th ed. p. 200-201 MPL: 0.75 566. Following a fad diet of skimmed milk and yogurt, an adult female patient experiences abdominal distention, nausea, cramping, and pain followed by watery diarrhea. This set of symptoms is observed each time the said meal is consumed. A most likely diagnosis is: A. Steatorrhea B. Lactase deficiency C. Sialidase deficiency D. Lipoprotein deficiency Ref: Harper’s Biochemistry 24th ed. p. 645 MPL: 0.1 77 567. Which of the following enzymes catalyzes the high-energy phosphorylation of substrates during glycolysis? A. Pyruvate kinase B. Phosphoglycerate kinase C. Triosephosphate isomerase D. Glyceraldehyde-3-phosphate dehydrogenase Ref: Harper’s Biochemistry 24th ed. p.176 MPL: 1.0 568. Which of the following enzymes is common to both glycolysis and gluconeogenesis? A. Pyruvate carboxylase B. Hexokinase C. Phosphoglycerate kinase D. Fructose 1,6-bisphosphatase Ref: Harper’s Biochemistry 24th ed. p.194 MPL: 0.75 569. During the first week of a diet of 1500 calories per day, the oxidation of glucose via glycolysis in the liver of a normal 59-kg woman is inhibited by the lowering of which of the following? A. Citrate B. ATP C. Ketone bodies D. Fructose-2,6-bisphosphatase Ref: Harper’s Biochemistry 24th ed. p.176 MPL: 0.75 570. Familial fructokinase deficiency causes no symptoms because: A. Hexokinase can phosphorylate fructose. B. Most tissues utilize fructose. C. Liver fructose-1-phosphate aldolase is still active. D. Excess fructose spills into the bowel and is eliminated in the feces. Ref: Harper’s Biochemistry 24th ed. p. 214 MPL: 0.75 571. Which of the following enzymes catalyzes phosphorylation with the use of inorganic phosphate? A. Hexokinase B. Phosphofructokinase C. Phosphoglycerate kinase D. Glyceraldehyde-3-phosphate dehydrogenase Ref: Harper’s Biochemistry 24th ed. p. 179 MPL: 0.75 572. After a well-rounded breakfast, which of the following would be expected to occur? A. Increased activity of pyruvate carboxylase B. Decreased activity of acetyl CoA carboxylase C. Decreased rate of glycogenesis D. Decreased rate of protein synthesis 78 Ref. MPL: 573. Harper’s Biochemistry 24th ed. p. 179 0.75 Contraction of skeletal muscle is initiated by the binding of calcium to: A. Tropomyosin B. Troponin C. Myosin D. Actomyosin Ref. Harper’s Biochemistry 24th ed. p. 687-688 MPL: 0.75 574. Which of the following statements correctly describes transport of oxygen by hemoglobin? A. Oxygen binds to hemoglobin more avidly than does carbon monoxide. B. The binding of oxygen to hemoglobin causes a valence change in the iron of the heme moiety. C. Each of the four heme moieties binds oxygen independently D. The plot of percentage of oxygen bound versus oxygen pressure is sigmoid in shape Ref. Harper’s Biochemistry 24th ed. p. 436 MPL: 0.75 575. Which of the following mutations would produce a severe form of thalassemia? A. Deletion of one α-globin locus B. Deletion of one β-globin locus C. Oxidation of heme groups to produce methemoglobin D. Altered RNA processing at both Ref. Harper’s Biochemistry 24th ed. p. 734 MPL 0.75 576. An increased affinity of hemoglobin for oxygen may result from which of the following? A. Initial binding of oxygen to one of the four sites available in each deoxyhemoglobin molecule B. High pH C. High carbon dioxide levels D. High 2,3-bisphosphoglycerate levels within erthrocytes Ref. Harper’s Biochemistry 24th ed. p. 436 MPL 0.75 577. The functions of many enzymes, membrane transporters, and other proteins can be quickly activated or deactivated by phosphorylation of specific amino acid residues catalyzed by enzymes called: A. Cyclases B. Kinases C. Phosphatases D. Proteases Ref. Harper’s Biochemistry 24th ed. p. 64-65 MPL 0.75 79 578. The Vmax of the enzyme is the: A. Reciprocal of the absolute value of the intercept of the curve with the x-axis B. Reciprocal of the absolute value of the intercept of the curve with the y-axis C. Absolute value of the intercept of the curve with the x-axis D. Slope of the curve Ref. Harper’s Biochemistry 24th ed. p. 75-90 MPL 0.75 579. In the study of enzymes, the sigmoidal plot of substrate concentration versus reaction velocity may indicate: A. Michaelis-Menten Kinetics B. Myoglobin binding oxygen C. Cooperative binding D. Competitive inhibition Ref. Harper’s Biochemistry 24th ed. p. 75, 90 MPL 1.0 580. A non competitive inhibitor of an enzyme: A. Increases Km with no or little change in Vmax B. Decreases Km and decreases Vmax C. Decreases Vmax D. Increases Vmax Ref. Harper’s Biochemistry 24th ed. p. 86-88 MPL 0.75 581. Which of the following statements correctly describes allosteric enzymes? A. Effectors may enhance or inhibit substrate binding B. They are not usually controlled by feedback inhibition C. The regulatory site may be catalytic site D. Michaelis-Menten kinetics describe their activity Ref. Harper’s Biochemistry 24th ed. p. 104-105 MPL 0.75 582. Which of the following enzymes is regulated primarily through allosteric interaction? A. Chymotrypsin B. Pyruvate dehydrogenase C. Glycogen phosphorylase D. Aspartate transcarbamoylase Ref. Harper’s Biochemistry 24th ed. p. 104-105 MPL 0.75 583. Which of the following statements about flavoproteins is TRUE? A. They are not oxidized by coenzymeQ B. They receive electrons from cytochrome P450 in liver mitochondria C. They do not participate in oxidation of NADH dehydrogenises D. They can be associated with sulfur and nonheme iron Ref. Harper’s Biochemistry 24th ed. p. 117-118 MPL 0.75 80 584. Which of the following compounds is a member of the electron transport chain? A. Octanoyl carnitine B. Cytochrome c C. NADH D. Palmitoyl carnitine Ref. Harper’s Biochemistry 24th ed. p. 128 MPL 0.75 585. All known effects of cyclic AMP in eukaryotic cells result from: A. Activation of the catalytic unit of adenylate cyclase B. Activation of synthetases C. Activation of protein kinase D. Stimulation of calcium release from the endoplasmic reticulum Ref. Harper’s Biochemistry 24th ed. p. 165 MPL 0.75 586. The connection between oxidative phosphorylation and electron transport is BEST described by: A. Existence of higher pH in the cisternae of the endoplasmic reticulum than in the cytosol. B. Synthesis of ATP as protons into the mitochondrial matrix along a proton gradient that exist across the inner mitochondrial membrane C. Dissociation of electron transport and oxidative phosphorylation D. Absence of ATPase in the inner mitochondrial membrane Ref. Harper’s Biochemistry 24th ed. p. 127 MPL 0.75 587. If all potential sources of ATP production are taken into account, the net number of ATP molecules formed per molecule of glucose in aerobic glycolysis is: A. 2 B. 6 C. 18 D. 36 Ref. Harper’s Biochemistry 24th ed. p. 176-184 MPL 0.75 588. Which of the following reactions generates ATP/ A. Glucose 6-phosphate to Fructose 6-phosphate B. Glucose to Glucose 6-Phosphate C. Fructose 6-phosphate to Fructose 1,6-bisphosphate D. Phosphoenolpyruvate Ref. Harper’s Biochemistry 24th ed. p. 176-184 MPL 0.75 81 589. Which of the following products of triacylglycerol breakdown and subsequent β-oxidation may undergo gluconeogenesis? A. Propionyl CoA B. Acetyl CoA C. All ketone bodies D. Some amino acids Ref. Harper’s Biochemistry 24th ed. p. 284 MPL 0.75 590. Inhibition of ATP synthesis during oxidative phosphorylation by oligomycin is thought to be due to: A. Blocking of the proton gradient between NADH-Q reductase & QH2 B. Blocking of the proton gradient between cytochrome C1 and cytochrome C C. Dissociation of cytochrome c from mitochondrial membranes D. Inhibition of mitochondrial ATPase Ref. Harper’s Biochemistry 24th ed. p. 701 MPL 0.75 591. The reactions of the urea cycle occur: A. In the cytosol B. In the mitochondrial matrix C. In the mitochondrial matrix & the cytosol D. Only in lysosomes Ref. Harper’s Biochemistry 24th ed. p. 301-380 MPL 0.75 592. The thyroid hormone thyroxine (T4) is derived from: A. Threonine B. Tyrosine C. Thiamine D. Tryptophan Ref. Harper’s Biochemistry 24th ed. p. 534-536 MPL 0.75 593. Which of the metabolites below is a precursor of tyrosine? A. L-dihydroxyphenylalanine (DOPA) B. Dopamine C. Norepinephrine D. Phenylalanine Ref. Harper’s Biochemistry 24th ed. p. 296-297 MPL 0.75 594. Which clinical laboratory observation is suggestive of Hartnup’s disease? A. High fecal levels of tryptophan and indole derivatives B. Elevated plasma tyrosine and methionine levels C. Elevation of glutamine in blood and urine D. Extremely high levels of citrulline in urine Ref. Harper’s Biochemistry 24th ed. p. 322-325 MPL 0.75 82 595. The important receive group of glutathione in its role as antioxidant is: A. Serine B. Sulfhydryl C. Tyrosine D. Acetyl CoA Ref. Harper’s Biochemistry 24th ed. p. 753 MPL 0.75 596. A newborn develops jaundice that requires laboratory evaluation. Which of the following porphyrin derivatives is conjugated, reacts directly, and is a major component of bile? A. Stercobilin B. Biliverdin C. Bilirubin D. Bilirubin diglucuronide Ref. Harper’s Biochemistry 24th ed. p. 356 MPL 0.75 597. Which of the following poryphrins give stools their characteristic brown color? A. Biliverdin B. Urobilinogen C. Heme D. Stercobilin Ref. Harper’s Biochemistry 24th ed. p. 354 MPL 0.75 598. Ceramide is a precursor to which of the following compounds? A. Phosphatidyl serine B. Sphingomyelin C. Phosphatidyl glycerol D. Phosphatidyl choline Ref. Harper’s Biochemistry 24th ed. p. 250-252 MPL 0.75 599. Humans MOST easily tolerate a lack of which of the following nutrients? A. Protein B. Iodine C. Carbohydrate D. Lipid Ref. Harper’s Biochemistry 24th ed. p. 285-286 MPL 0.75 600. A deficiency in Vitamin B12 causes: A. Cheilosis B. Beriberi C. Pernicious anemia D. Scurvy Ref. Harper’s Biochemistry 24th ed. p. 612-613 83 MPL 0.75 601. Which of the following vitaminswould MOST likely become deficient in a person who develops a completely carnivorous lifestyle? A. Thiamine B. Niacin C. Cobalamin D. Vitamin C Ref. Harper’s Biochemistry 24th ed. p. 612-613 MPL 0.75 602. 603. Biotin is involved in which of the following types of reactions? A. Hydroxlations B. Carboxylations C. Decarboxylations D. Dehydrations Ref. Harper’s Biochemistry 24th ed. p. 606-607 MPL 0.75 Which of the following conditions would primarily produce a functional deficiency of Vitamin K? A. Coumadin Therapy B. Broad Spectrum antibiotic C. Premature birth D. Lack of red meat in the diet Ref. Harper’s Biochemistry 24th ed. p. 727 MPL 0.75 604. A 3 month old boy presents with poor feeding & growth, hypotonia, lactic acidemia, and mild acidosis. The pyruvate to lactate ratio is high, and there is decreased conversion of pyruvate to Acetyl CoA. Which of the following may be considered for therapy? A. Thiamine B. FFA C. Biotin D. Vitamin C Ref. Harper’s Biochemistry 24th ed. p. 183 MPL 0.25 605. A 2-year old child presents with cough and bronchitis, growth failure, & chronic diarrhea with light-colored foul smelling stools. A deficiency of which vitamin should be considered? A. Vit B6 B. Vit C C. Vit A D. Vit B1 Ref. Harper’s Biochemistry 24th ed. p. 614-617 MPL 0.25 84 606. An infant presents with prominent forehead, bowing of the limbs, broad & tender wrists, swelling at the costochondral junction of the ribs, and irritability. Which of the following treatments is the most appropriate for this patient? A. Removal of eggs from diet B. Milk & Sunlight exposure C. Diet of baby food containing liver & ground beef D. Diet of baby food containing leafy vegetables Ref. Harper’s Biochemistry 24th ed. p. 613 MPL 0.25 607. Allopurinol effectively treats gout but has NO effect on the severe neurological symptoms of Lesch-Nyhan patients because it does not: A. Decrease de Novo purine synthesis B. Decrease de Novo Pyrimidine syntheis C. Inhibit xanthine oxidase D. Increase PRPP levels Ref. Harper’s Biochemistry 24th ed. p. 378 MPL 0.75 608. Which of the following would rule out hyperuricemia in a ptient? A. Lesch-Nyhan synthesis B. Gout C. Carbonage phosphate deficiency D. Xanthine oxidase hyperactivity Ref. Harper’s Biochemistry 24th ed. p. 381 MPL 0.75 609. Which of the following contributes nitrogen atom to both purine & pyrimidine rings? A. Aspartate B. Carbonage PO4 C. CO2 D. None of the above Ref. Harper’s Biochemistry 24th edition P. 376-377 MPL 1.0 610. What is the end product of fatty acid synthase activity in human? A. Palmitic acid B. Palmetoleic acid C. Linoleic D. Arachidonic acid Ref. Harper’s Biochemistry 24th ed. p. 216-223 MPL 0.75 611. For every 2 moles of free glycerol released by lipolysis of triglycerides in adipose tissue? A. 1 mole of glucose can be synthesized via gluconeogenesis B. 2 moles of triacrylglyceride is released C. 2 moles of FFA is released D. 3 moles of Acyl CoA is produced 85 Ref. Harper’s Biochemistry 24th ed. p. 267 MPL 0.75 612. A 45 year old man ha s a mild heart attack and is placed on diet and Mevastatin therapy. Which of the following will result in this therapy? A. Low blood glucose level B. Low blood LDLs C. High blood cholesterol D. Low oxidation of Fa Ref. Harper’s Biochemistry 24th ed. p. 281 MPL 0.75 86