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IEA Biochemistry Mock Midterm
Spring 2003
1. Which of the following statements concerning chemical reactions in the human body is incorrect?
A. Due to the non-specific nature of enzymes, many reactions are able to be carried out in the human
body that would otherwise proceed very slowly or not at all in nature.
B. Cellular compartmentalization helps dictate which reactions may occur.
C. The energetics of chemical reactions obey the laws of thermodynamics.
D. All the above are true.
2. Which of the following statements is false?
A. Catabolism is the process by which large biochemical molecules are broken down by cells to harness
the released free energy.
B. Most biochemical reactions require enzymes in order to carry out reactions that would otherwise be
thermodynamically unfavorable.
C. Lipids are one of 4 major compounds involved in biochemical reactions
D. All of the above are true.
3. A solution has a pH of 4. What is the hydroxide concentration at this pH?
A. 1010
B. 10-10
C 104
D.10-4
4. Which of the following statements is false?
A. Weak acids do not undergo complete dissociation when dissolved in water.
B. Weak acids can either be organic or inorganic compounds.
C. At its pKA value weak acids are 50% dissociated.
D. Altering the pH of a solution from 5 to 10 involves a doubling of its hydrogen concentration.
5. All the following characterize water as a solvent except?
A. Water is a good solvent for salts but not effective for other polar molecules like D-glucose.
B. Hydrogen bonds between -OH/-OH interactions are very important in determining the conformations
of proteins and nucleic acid molecules.
C. Water’s polar nature allows it to actually break certain electrostatic bonds.
D. Two or more of the above are incorrect.
6. Which of the following values represents the change in hydrogen ion concentration when the pH of a
solution is reduced from 6 to 4?
A. Decrease by 2
B. Decrease by 100
C. Increase by 200
D. Increase by 100
7. Which of the following statements about acids is false?
A. A good buffering system against acidic insult will have a higher concentration of conjugate base than
acid.
B. A weak base in association with its conjugate acid acts as a good buffer only within about on pH unit on
either side of its pKA value.
C. At its pKA value a weak acid is 50% dissociated.
D. All the above are true Statements.
8. Which of the following statements is false?
A. There are 20 amino acids that are actually put into the protein during synthesis.
B. In humans there are more than 20 amino acids found in proteins.
C. All amino acids except for glutamate can exist as mirror images.
D. L or D does not denote the direction in which the plane of polarized light is rotated.
9. Which of the following is incorrect concerning amino acids?
A. D and L isomers rotate the plane of polarized light in opposite directions.
B. D and L isomers have the same chemical and physical properties therefore they have the same
reaction rates with reagents.
C. All AAs found in proteins and most other AAs of biochemical significance have the L-configuration.
D. D- amino acids do occur in nature
10. Which of the following will have the highest hydropathy rating?
A. Leu
B. Arg
C. Tyr
D. Gly
11. The Leucine Zipper is characterized by all of the following except?
A. It is a variation of the alpha helix
B. it is formed by the interdigitation of leucine residues
C. The creation of the “zipper” forms a polar hydrophilic strip.
D. It is an example of a super secondary structure
12. Which of the following is incorrect about peptide bonds?
A. There is no free rotation about the pi bond
B. The peptide bond is charged at physiological pH.
C. amino acids are joined by amide linkages.
D. All the above are true
13. Which of the following is the closest to the PI for Histidine?
A. 6.5
B. 8.5
C. 5.5
D. 7.5
14. Which of the following would you use to break disulphide bonds?
A. 8 M UREA
B. Sulfuric Acid
C. Mercaptoethanol
D. None of the above
15. Which of the following amino acids in an integral membrane protein would you most likely find on the
extracellular surface?
A. Phe
B. Gly
C. His
D. Asn
16. Which of the following is incorrect concerning beta pleated sheets?
A. in the parallel β-pleated sheet, adjacent poplypeptide chains run in the same direction.
B. In the antiparallel β -pleated sheet, the carboxyl end of one chain is aligned next to the amino termini
of its immediate neighbors.
C. The nature of amino side chains are important only in determining weather it will be an alpha helix.
For the β pleated sheet, AA side chains are not important.
D. All the above are correct
17. Which of the following statements is true concerning proteins?
A. There are two main groups of proteins, fibrous and globular.
B. Proteins are polymers of D-alpha amino acids joined by amide linkages between the carboxyl group
of one amino acid and the amino group of its neighbor.
C. The alpha helix is a type of tertiary structure
D. A and B are both correct.
18. Which of the following is the reason why proline can’t participate in formation of the alpha helix.
A. It has no carboxyl group capable of forming the appropriate linkage.
B. Due to its size the steric hindrance can’t be overcome by the developing helix.
C. It has no H attached to the amide nitrogen.
D. None of the above are true.
19. Which of the following is correct concerning the alpha helix
A. It has 5.4 AA residues per turn
B. All alpha helices in proteins are left handed
C. The AA side chains are found outside the helix.
D. None of the above are true.
20. Which of the following statements concerning collagen is true:
A. The amino acid sequence in collagen polypeptides is quite variable but there are consistent ratios of
amino acids represented in the overall structure.
B. There are less than 5 types of collagen found in tissues.
C. Tropocollagen consists of 3 polypeptide chains of which each is left handed and alpha helical in
nature.
D. Propeptides are required for rapid formation of the TC triple helix.
21. Which of the following is true concerning cross linking in tropocollagen molecules?
A. Collagen microfibrils have the same physical characteristics in vitro as in vivo because of the
effective cross linking in tropocollagen formation.
B. The initial step in initiating cross linking is conversion of lysine to hydroxylysine by the action of
lysyl oxidase
C. Lysyl oxidase is a iron containing protein
D. Lysyl oxidase acts on lysine and hydroxylysine throughout the length of the tropocollagen molecule.
22. Which of the following is incorrect about the synthesis, secretion and assembly of collagen?
A. Formation of the -S-S- bridges occurs outside the fibroblast.
B. The form of collagen secreted by the fibroblast is referred to as procollagen
C. Formation of the cross links occurs prior to procollagen formation.
D. Triple helix formation occurs inside the fibroblast.
23. Which of the following is not associated with defective collagen:
A. Menkes Syndrome
B. Marfans Syndrome
C. EDS type VII
D. Osteogenesis imperfecta.
24. Which of the following is correct concerning ascorbic acid (Vit C. :
A. It can only be made by humans if the right combinations of amino acids are ingested.
B. It is required in order to keep prolyl hydroxylase and lysyl hydroxylase in their active form.
C. Vitamin C is keeps copper in its reduced form.
D. All the above are correct.
25. EDS Type VI is caused by:
A lysyl hydroxylase deficiency
B. procollagen aminopeptidase deficiency
C. Lysyl oxidase deficiency
D. None of the above
26. Which is true of the allysine and hydroxyallysine pathways:
A. Histidine aldol cross links occur as a result of both the hydroxyallisine pathway and the allysine
pathway.
B. In the allysine pathway you have the formation of a Schiff base.
C. In the hydroxyallysine pathway there is a non-enzymatic aldol condensation prior to lysyl oxidase
activity.
D. None of the above are correct.
27. Glycogen consists of:
A. glucose residues linked by alpha 1-4 bonds
B. glucose residues linked by alpha 1-6 bonds
C. galactose residues linked by alpha 4-4 bonds
D. glucose residues linked by alpha 4-4 bonds
E. glucose residues linked by alpha 4-4 bonds with glucose alpha 1-6 branch points
28. glycogen breakdown in muscle cells:
A. is initiated by glucagon
B. is initiated by epinephrine
C. produces glucose-1-phosphate in the final step
D. activates protein kinase A and leads to decreased levels of cAMP
E. activates phosphodiesterase
29. the glucose donor in glycogen biosynthesis is:
A. Glucose-1-p
B. Glucose-6-p
C. UDP-Glucose
D. Alpha-dextrin residues
E. Maltose units
30. Deficiency of liver phosphorylase:
A. Pompe's disease
B. von Gierke's disease
C. Her's Disease
D. McArdle's syndrome
E. Tarui's disease
31. The activity level of the enzyme phosphoenolpyruvate carboxykinase:
A. Is increased by high levels of insulin
B. Is increased during the well fed state
C. Is decreased by circulating epinephrine
D. Is decreased by circulating glucagon
E. Is controlled at the level of gene expression
32. Decreased levels of fructose-2,6 bisphosphate:
A. Are caused by a high insulin/glucagon ratio
B. Are associated with decreased protein kinase a activity
C. Occur when the PFK-2/FBP-2 complex is dephosphorylated
D. Lead to an increased rate of gluconeogenesis
E Lead to a decreased rate of gluconeogenesis
33. The pentose phosphate pathway:
A. Consumes 2 ATP per pentose sugar produced
B. Produces NADPH for biosynthetic reactions
C. Occurs in the mitochondria
D. Is very active in skeletal muscle
E. Is controlled at the transketolase step
34. Drug induced hemolytic anemia:
A. Is caused by lysis of red blood cells due to increased levels of NADPH
B. Is caused by the reduced form of glutathione in red blood cells
C. Is caused by deficiency of glucose-6-phosphate dehydrogenase in red blood cells
D. Low levels of hydrogen peroxide in the red blood cell
E. Is an autosomal recessive disorder
35. The pyruvate dehydrogenase reaction:
A. Allows production of carbohydrate from fat
B. Requires coenzyme A and lipoic acid
C. Is a cytosolic reaction
D. Is a multienzyme complex requiring biotin
E. Is reversible in states of excess substrate
36. The mitochondrial malate-aspartate shuttle:
A. Ooccurs exclusively in the liver
B. Has a higher thermodynamic effiency than the glycerolphosphate shuttle
C. Results in 2 ATP produced per NADH
D. Is very active in red blood cells
E. Transports malate out of the mitochondria and alpha ketoglutarate into the mitochondria
37. Which statement is correct:
A. Galactose is a C4 epimer of glucose
B. Mannose is a C3 epimer of glucose
C. Glucose is a furanose sugar
D. In the beta configuration of cyclic hemiacetals, the OH group points down
E. Arabinose is a 7c sugar
MATCHING --pick one for each question:
38. Sorbitol
39. Ascorbic acid
40. Maltose
41. Sucrose
42. Lactose
A. glucose residues linked by alpha 1-4 bond
B. glucose and fructose linked by alpha 1-2 bond
C. Gal and glucose linked by beta 1-4 bond
D. gamma lactone
E. glucose alcohol
43. Which of the following is true:
A. Glucokinase is expressed in the liver and has a high Km which enables the liver to respond quickly
following a high carbohydrate meal
B. Following a high carbohydrate meal, glycogenolysis and glycogen synthesis occur at increased rates
C. Glucose enters hepatocytes by insulin mediated active transport
D. Fructose 2,6 bisphosphate is a potent inhibitor of PFK-1
E. AMP is an allosteric inhibitor of PFK-1
44. High levels of NADH will:
A. Activate isocitrate dehydrogenase
B. Inhibit isocitrate dehydrogenase
C. Activate citrate synthase
D. Inhibit citrate synthase
E. More than 1 of the above
45. Which of the following is correct:
A. Glucagon is produced by beta cells of pancreatic islets
B. Pyruvate kinase is active when phosphorylated
C. Glucagon stimulates conversion of pyruvate kinase into its inactive form
D. Activation of pyruvate carboxylase occurs in the well fed state
E. Fasting is associated with active phosphofructokinase
46. Where are the majority of the plasma proteins synthesized?
A.
B.
C.
D.
E.
Spleen
Liver
Thymus
Bone Marrow
Plasma Cells
47. Which of the following is not true of albumin?
A. It is involved in osmotic regulation between blood and tissues.
B. It can bind and transport hydrophobic compounds because it contains several hydrophobic binding
clefts.
C. In renal disease, the albumin levels are extremely elevated.
D. Analbuminemia is a rare genetic disorder characterized by very low levels of albumin
E. Albumin can transport drugs such as aspirin and sulphonamides
48. Which plasma protein is a major component of Beta-Globulins and binds to Fe3+ to transport it to
tissues, especially bone marrow and liver?
A.
B.
C.
D.
E.
Transferrin
Macroglobulin
Beta-Lipoprotein
alpha-Fetoprotein
Hemopexin
49. Which of the following is true of hemoglobin?
A.
B.
C.
D.
E.
The iron atom in heme is capable of making 8 bonds.
Hb can only carry oxygen when the iron is in the Fe3+ form.
Hb consist of 4 subunits, 3 alpha units and 1 Beta unit.
Hb can bind C02 200 times more tightly than O2.
Hemoglobin to which Carbon Monoxide is attached is called carboxyhemoglobin
50. All of the following regarding hemoglobin are false except?
A.
B.
C.
D.
E.
The O2 binding curve of Hb is not sigmoidal, but is hyberbolic shaped.
Hb binds O2 much less strongly at low oxygen tension.
Subunits of Hb can exist in three conformational forms.
The Tense form has a high oxygen affinity.
The subunits of deoxyHb exist in the Relaxed form.
51. What is the mechanism by which 2,3-Bisphosphoglycerate (BPG) lowers affinity of Hb for oxygen?
A. It stabilizes the deoxyHb structure by making salt bridges between the two Beta chains.
B. It attaches to a site on the outside of Hb changing the conformation of Hb thus lowering oxygen
affinity.
C. BPG protonates the histidine residues at the C-terminal end of the Beta chains enabling them to form
salt linkages stabilizing the deoxyHb form.
D. It removes one of the alpha subunits allowing less oxygen to bind.
E. Reacts with the terminal amino groups of alpha chains to form carbamates.
52. Which class of enzymes catalyse reactions involving isomerization?
A. Oxidoreductases
B. Isomerases
C. Ligases
D. Hydrolases
E. Tranferases
53. Some complex enzymes require non-protein organic molecules known as
A.
B.
C.
D.
zymogens
apoenzyme
cofactor
metalloenzyme
54. Glucokinase and Hexokinase have different primary structures but are capable of catalyzing the same
reaction, so they are known as?
A.
B.
C.
D.
E.
Apoenzymes
Metalloenzymes
Cofactors
Multienzymes
Isoenzymes
55. Regarding effects of temperature on enzyme function, which is true?
A. An increase in temperature will increase the rate of reaction and decrease the rate of destruction of
the enzyme thus leading to better enzyme function.
B. Enzymes have an optimum temperature.
C. Organisms have an optimum temperature
56. Which of the following statements is false?
A. Enzymes catalyze reactions by bringing reactants together with proper spatial relationship for
reaction to occur.
B. General acid-base catalysis utilizes proton transfer.
C. Metal ions bind weakly to enzymes during catalytic activity
D. Catalysis alters the equilibrium point.
E. Catalysis is a process that increases the rate at which a reaction approaches equilibrium
57. Which of the following statesments regarding Maximum velocity (Vmax) is false?
A.
B.
C.
D.
E.
Vmax is the maximum velocity (rate of reaction) attainable
The lower the Vmax, then the more product is formed per minute.
Vmax is a measure of the catalytic effectiveness of the enzyme.
Remains unchanged in presence of competitive inhibitor.
Decreases in presence of noncompetitive inhibitor.
58. Michaelis constant (Km)
A.
B.
C.
D.
is defined as the concentration of substrate needed to produce half the maximum velocity
is a constant that does not vary with different types of enzymes.
that is high indicates a greater affinity of enzyme for the substrate.
is defined as the concentration of substrate needed to reach the maximum velocity possible for the
enzyme.
E. cannot be determined graphically.
59. Lineweaver-Burk plot will give info on?
A.
B.
C.
D.
E.
The y-intercept is Vmax
The slope of the line is Vmax/Km
x-intercept is -1/Km
The major disadvantage of the plot is low [S] are crowded near y-axis
y-intercept is -Km
60. Diisopropylfluorophosphate (DFP) is an irreversible inhibitor and it covalently bonds to
A.
B.
C.
D.
E.
Carboxyl groups of amino acids in the enzyme
Transition metals of enzyme
Thioester groups of enzymes
Hydroxy group of serine of enzyme
Amide groups of amino acids in enzyme
61. Competitive inhibition:
A.
B.
C.
D.
E.
can be overcome by increasing [S]
are usually not structural analogs of the substrate and bind to positions far from binding site.
will lower Vmax
will decrease Km
will decrease the slope of the line in Lineweaver-Burk Plot
62. Regarding the enzymes used in diagnosis of MIs which of the following is true?
A.
B.
C.
D.
E.
If the ratio of CKMB2:CKMB1 is less than 1.5:1 then MI is suspected
There is a significant rise in levels of LDH-4 in blood following a heart attack.
Strong indicator of MI is an increase above 25% CKMB activity relative to total CK activity
Myoglobin is highly specific indicator of MI but lacks sensitivity
Troponins provide a long term indicator of MI because they remain elevated for 5-7 days.
63. What is meant by the LDH 1,2-Flip?
A.
B.
C.
D.
E.
LDH 1 and 2 will flip to an inactive form after an MI
LDH 1 and 2 cannot be detected in serum following a MI
The blood levels of LDH-1 exceed the levels of LDH-2 following a MI
LDH-1 is converted to LDH-2 following a MI
A MI will cause decrease both the level of LDH-1 and LDH-2
64. The First Law of Thermodynamics states:
A.
B.
C.
D.
E.
that a spontaneous process will not occur if there isn’t enough free energy.
that entropy always decreases.
that chemical energy cannot be transformed into thermal or mechanical energy.
in any process the total energy of the system plus surroundings remains constant.
that energy is lost and cannot be reproduced.
65. Standard Free Energy change:
A.
B.
C.
D.
E.
does not have anything to do with reactants concentrations.
cannot be used in experiments
is used for conditions in the human body
cannot be related to free energy at prevailing conditions.
is the free energy change at set concentrations of 1 molar and 289 K temp.
66. Reaction rate is determined by:
A.
B.
C.
D.
E.
activation energy
entropy of system
entropy of surroundings
equilibrium point of reaction
energy required to achieve half the transition state
67. Which of the following will phosphorylate ADP ATP
A.
B.
C.
D.
E.
Glucose 1-phosphate
Glycerol Phosphate
AMP
Phosphoenolpyruvate
Fructose 6-Phosphate
68. Which of the following concerning the electron transport chain is FALSE?
A.
B.
C.
D.
E.
NADH dehydrogenase utilizes a flavin mononucleotide as an electron acceptor
Cytochrome A and A3 contain heme groups
The electron transport chain is located in the outer mitochondrial space
The electron transport chain consists of proteins with the exception of coenz Q
Oxygen is the final electron acceptor in the electron transport chain
69. A Red/Ox pair with a highly negative standard reduction potential indicates:
A.
B.
C.
D.
E.
A higher tendency of the oxidized member of the pair to accept electrons
A lower tendency of the reduced member of the pair to donate electrons
No transfer of electrons will occur
A higher tendency of the reduced member of the pair to donate electrons
Electrons are tightly bound to the reduced member of the pair
70. Coenzyme Q is the intermediate electron carrier between which of the following?
A.
B.
C.
D.
E.
Complex III and Complex IV
Complex IV and Complex V
Complex I and Complex III
Complex II and Complex I
Complex I and Complex V
71. Which of the following redox pairs will provide the greatest ΔG°?
A.
B.
C.
D.
E.
NAD / NADH -0.32
FMN / FMNH2 -0.22
Pyruvate / lactate -0.19
Cytochrome C (Fe3+ / Fe2+) +0.07
.5 O2 / H20
+0.82
72. The production of ATP in the mitochondrial matrix relies on which of the following?
A.
B.
C.
D.
E.
Spontaneous assembly
A proton gradient between the outer membrane and the cytosol
A proton gradient between the inner membrane and the outer membrane space
An oxygen gradient between the cytosol and outer membrane space
Enzyme-independent processes
73. Antimycin A inhibits electron transfer between which of the following?
A.
B.
C.
D.
E.
NADH and coenzyme Q?
NADH and FMN?
Cytochrome C and Cytochrome a + a3?
Cytochrome B and Cytochrome C?
Cytochrom a + a3 and O2?
74. Which of the following compounds increases the permeability of the inner mitochondrial membrane
to protons?
A. Rotenone
B. Amytal
C. CN
D. CO
E. 2,4-dinitrophenol
75. A researcher isolated rat mitochondria and performed an experiment to measure the effects of adding
various compounds. All conditions were identical to normal human values. Oxygen consumption, ATP
production, and Heat were measured. The addition of compound X produced a marked increase in ATP
production as well as an increased oxygen consumption value, however when she added compound Z to the
culture she noted a marked production of heat along with no ATP production.
Which of the following is compound Z?
A.
B.
C.
D.
E.
CO
Rotenone
Antimycin A
2,4-dinitrophenol
7M HCl
76. Concerning mitochondrial DNA, which of the following is FALSE?
A.
B.
C.
D.
E.
The vast majority of mitochondrial enzymes are produced in the nucleus
Nuclear DNA encodes the majority of mitochondrial enzymes
Mitochondrial DNA contains the majority of its enzymes
Nuclear proteins are transported to mitochondria
mDNA is maternally inherited
77. The respiratory burst associated with phagocytosis produces which of the following?
A.
B.
C.
D.
E.
Nitric oxide
SuperOxide ion
Nitrous oxide
Nitrogen dioxide
Sulfer Dioxide
78. Which of the following does not participate in the neutralization of free radicals?
A.
B.
C.
D.
E.
Vitamin C
Vitamin E
Glutathione peroxidase
Catalase
Myeloperoxidase
79. Free Radical neutralization in hydrophobic regions of the cell is primarily done by:
A.
B.
C.
D.
E.
Vitamin C
Vitamin A
Vitamin E
Vitamin D
Vitamin K
Matching:
80.
81.
82.
83.
84.
Pyruvate Dehydrogenase
Aconitase
Fumarase
Succinate thiokinase
Citrate Synthase
a.)isomerizes citrate
b.)multienzyme complex
c.)requires acCOA
d.)hydrates fumarate
e.)results in GTP formation
f.)results in CO2 production
85. Which of the following is TRUE?
A.
B.
C.
D.
E.
The ω carbon is found at position 18 in all fatty acid molecules
Lipid fluidity increases with increasing saturation
Cardiolipin is found exclusively in the mitochondrial membrane
Position #1 of DAG and TAG is usually unsaturated
In biological membranes, lipids and proteins are held together by covalent bonds
86. Which of the following statements about lipid digestion is FALSE?
A. Pancreatic lipase preferentially removes Fatty Acids from the 1 and 3 positions of TAG
B. Esterases are colipases that help to hydrolyze FA from cholesterol esters. The resultant NEFAs
enter the intestinal mucosal cells by diffusion
C. Chylomicrons are formed within mucosal epithelial cells
D. TAG synthesis occurs in the smooth ER via the Kennedy pathway
E. Glucagon stimulates TAG synthesis
87. Which of the following would result in steatorrhea (xs lipid in the feces)?
A.
B.
C.
D.
E.
Blocked bile duct
Blocked pancreatic duct
Diseased intestinal mucosal cells
Defective TAG transport via chylomicrons
All of the above
88. Which represents the number of Acyl CoAs produced and the number of turns of the β oxidation cycle,
respectively, for palmitic acid?
A.
B.
C.
D.
8, 7
9, 8
7, 8
8, 8
89. Which of the following is TRUE?
A. Short, medium and long chain Fatty Acids all use the same Acyl CoA Dehydrogenase in the β
oxidation pathway
B. CPT1 in the Carnitine shuttle is inhibited by Malonyl CoA
C. VLCFAs are catabolized in the mitochondrial matrix
D. Peroxisomal oxidation occurs in erythrocytes
90. Why does Medium Chain Acyl Dehydrogenase Deficiency (MCAD. result in hypoglycemia?
A. The products of FA oxidation are necessary for gluconeogenesis
B. The majority of the energy requirements of the body are being met with glucose now that MCFAs are
not being oxidized
C. Hypoglycin, a rare amino acid in the fruit of the ackee tree inhibits glucose uptake in the gut
91. The enzyme that interconverts UDP-galactose and UDP-glucose is called an epimerase. This name is
appropriate because glucose and galactose are epimers, which means that they are:
A. mirror images of each other
B. ketoses rather than aldoses
C. hexoses of the L configuration
D. monosaccharides that differ only in the position of one hydroxyl group
E. disaccharides that contain a -1,4 glycosidic bonds
92. Which of the following statements concerning GAGs is True?
A. they rarely contain sulfate groups
B. they contain branches of N-acetylneuraminic acid
C. they contain short oligosaccharide chains
D. they contain repeating disaccharides
E. they are usually positively charged
93. Mucopolysaccharidoses are a family of diseases characterized by all of the following EXCEPT:
A. deficiency in certain lysosomal enzymes
B. elevated urinary excretion of hyaluronic acid
C. some are genetically inherited
D. Swollen lysosomal vesicles
E. tissue accumulation of glycosaminoglycans
4)A patient has a genetic defect that causes intestinal epithelial cells to produce disaccharidases at a much
lower activity than normal. Compared with a normal person, after eating a bowl of milk and oatmeal
sweetened with table sugar, this patient will have higher levels of:
A. insulin in the blood
B. galactose and fructose in the blood
C. glycogen in the muscles
D. starch in the stool
E. maltose, sucrose, and lactose, in the stool
5) A 40 year old African American male comes to your office complaining of abdominal discomfort and
excessive passing of gas after eating dairy products. Your diagnosis will be:
A. Hurler’s syndrome
B. congenital lactase deficiency
C. adult onset lactose intolerance
D. McArdele’s Syndrome
E. Classical galactosemia
Questions 96-101: Choose the condition that would result from a deficiency of that enzyme. Use each
choice, once, more than once, or not at all.
A. Galactosemia
B. A hemolytic anemia
C. Fructose intolerance
D. lactose intolerance
E. McArdle’s disease
96. Lactase
97. Galactokinase
98. Aldolase B
99. Muscle Glycogen phosphorylase
100. Uridyl Transferase
101. Glucose-6-phosphate dehydrogenase
102. In an alcoholic with a thiamine deficiency, which enzyme of the pentose phosphate pathway would be
less active than normal?
A. epimerase
B. transaldolase
C. isomerase
D. transketolase
E. glucose 6-phosphate dehydrogenase
103. An adolescent patient with a deficiency of muscle phosphorylase was examined while exercising her
forearm by squeezing a rubber ball. Compared with a normal person performing the same exercise, this
patient:
A. could exercise for a longer period of time without fatigue
B. had increased glucose levels in blood drawn from her forearm
C. had decreased lactate levels in her blood drawn from her forearm
D. had lower levels of glycogen in biopsies of her forearm muscle
104. Which of the following is NOT a common feature of the carbohydrate structure in N-linked and Olinked glycoproteins?
A. their synthesis involves a lipid carrier
B. they may contain N-acetylneuramic acid
C. they may contain glucose
D. they are synthesized in the endoplasmic reticulum and the Golgi
E. they degradation in vivo involves action of lysosomal enzymes
105. A defect in aldolase B is the cause for which of the following:
A. essential fructosuria
B. hereditary fructose intolerance
C. galactosemia
D. galactosuria
E. lactose intolerance
106. Dietary fructose is phosphorylated in the liver and cleaved to form:
A. two molecules of dihydroxyacetone phosphate
B. one molecule of each dihydroxyacetone phosphate and glyceraldehydes
C. one molecule each of dihydroxyacetone phosphate and glyceraldehydes-3-phospate
D. one molecule of each dyhydroxyacetone and glyceraldehydes-3-phosphate
E. two molecules of glyceraldehydes-3-phosphate
107. Drug induced hemolytic anemia is caused by a deficiency in:
A. transketolase
B. transaldolase
C. glucose-6-phosphate dehydrogenase
D. phosphohexose isomerase
E. 3-epimerase
108. All of the following are characteristic of Hyaluronic Acid EXCEPT:
A. high molecular weight
B. synthesized in the golgi
C. it is covalently linked to protein
D. hydrogen bonding between adjacent sugar residues
E. found in sinovial fluid and vitreous humor of the eye
109. Lysosomal storage diseases also called mucopolysaccharidoses are characterized by all of the
following EXCEPT:
A. hepatosplenomegaly
B. joint stiffness
C. corneal clouding
D. coarse facial hair
E. adult onset
110. Excretion of dermatan sulfate and heparin sulfate in the urine, abnormality in development of skeletal
cartilage and bone, dwarfism, kyphosis, deformed limbs, and limitations of joint movement are features of:
A. Hunter’s Syndrome
b. Sanfilippo Syndrome
C. Hurler’s Syndrome
D. Sly’s Syndrome
E. Morquio A syndrome
1.A
2.B
3.B
4.D
5.A
6.D
7.D
8.C
9.B
10.A
11.C
12.B
13. D
14. C
15. D
16. C
17. A
18. C
19. C
20. D
21. B
22. C
23. B
24. B
25. A
26. D
27. A
28. B
29. C
30. C
31. E
32. D
33. B
34. C
35. B
36. B
37. A
38. E
39. D
40. A
41. B
42. C
43. A
44. E
45. C
46. B
47. C
48. A
49. E
50. B
51. A
52. B
53. C
54. E
55. C
56. D
57. B
58. A
59. C
60. D
61. A
62. E
63. C
64. D
65. E
66. A
67. D
68. C
69. D
70. C
71. A
72. C
73. D
74. E
75. D
76. B
77. B
78. E
79. C
80. B
81. A
82. D
83. E
84. C
85. C
86. E
87. E
88. A
89. B
90. B
91. D
92. D
93. B
94. E
95. C
96. D
97. A
98. C
99. E
100. A
101. B
102. D
103. C
104. A
105. B
106. B
107. C
108. B
109. E
110. C