Module General principles of metabolism Test questions in text form

part as coenzyme:
A. Ubiquinone
B. Lipoic acid
C. Carnitin
D. * Orotic acid
E. Pangamic acid
78. Some enzymes involved in the hydrolysis of ATP cannot function without help of sodium 
ions. Sodium in this case functions as
A. A substrate
B. * A cofactor
C. An active site
D. A noncompetitive inhibitor
E. A vitamin
79. Some enzymes involved in the hydrolysis of ATP cannot function without help of sodium 
ions. Sodium in this case functions as
A. A substrate
B. * A cofactor
C. An active site
D. A noncompetitive inhibitor
E. A vitamin

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80. Substrate binding site on the enzyme is
A. * Active site
B. Allosteric site
C. Prostetic group
D. Cofactor
E. All of above
81. Temperature optimum of enzymes - is:
A. * Temperature which speed of enzymatic reaction is maximal
B. Temperature which is denaturation of enzymes
C. A size speed of reaction is at the temperature of 48-560С
D. The best conditions of bringing together are between an enzyme and substrate
E. Temperature which metabolic processes are inhibits
82. The active site of an enzyme
A. Remains rigid and does not change shape
B. Is found at the center of globular enzymes
C. Is complementary to the rest of the molecule
D. * Contains amino acids without sidechains
E. None of the above choices are correct
83. The activity of a zymogen is activated by____________.
A. Covalent modifications
B. Allosteric regulation
C. Association/disassociation of subunits
D. * Proteolytic modification
E. None of the above
84. The amino acid ________ can function in proton transfer when present in the enzyme 
active site.
A. Glutamate
B. Aspartate
C. * Histidine
D. Lysine
E. All of the above
85. The apparent Km of an enzyme changes when the enzyme is treated with a_____.
A. Competitive inhibitor.
B. * Uncompetitive inhibitor.
C. Noncompetitive inhibitor
D. A and b.
E. B and c.
86. The coenzyme biotin is involved in the transferring of the following groups
A. Amino group
B. * CO2
C. One carbon group
D. Acyl group
E. Amino acid residues
87. The coenzyme present in isocitrate dehydrogenase
A. * NAD+
B. NADP+
C. FAD
D. TPP
E. Biotin
88. The coenzyme present in transaminase
A. NAD+
B. TPP

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C. Coenzyme A
D. * Pyridoxal phosphate
E. Biotin
89. The enzyme Creatine kinase levels are increased in the blood of patients with
A. Prostate cancer
B. * Hepatitis
C. Heart attack
D. Osteoporosis
E. Muscle atonia
90. The enzyme involved in bone formation
A. * Acid phosphatase
B. Urease
C. Alkaline phosphatase
D. Calcitonin
E. Catalase
91. The enzyme kinase requires
A. * Mg
B. Mn
C. K
D. Mo
E. Сu
92. The enzyme which transfer groups between atoms within a molecule are
A. Recemases
B. Mutases
C. * Transferases
D. Oxido-reductases
E. All of these
93. The enzymes are inherent all physical and chemical properties of proteins, except:
A. High molecular mass
B. Breaking up to amino acid during a hydrolysis
C. Formation of colloid solutions
D. Antigen properties
E. * Stable is to influence of high temperatures and salts of heavy metals
94. The equilibrium constant for the conversion of the disaccharide sucrose to the simple 
sugars glucose and fructose is 140,000. What can you conclude about the reaction: 
sucrose + H2Ooglucose + fructose?
A. It is a closed system
B. It never reaches equilibrium
C. It is spontaneous, starting with sucrose
D. The equilibrium constant increases when the starting concentration of sucrose is 
increased
E. * At equilibrium, the concentration of sucrose is much higher than the 
concentrations of glucose and fructose.
95. The equilibrium constant for the ionization of acetic acid, is 0.00002. What can you 
conclude about this reaction?
A. It is a closed system
B. * At equilibrium, the concentration of CH3COOH is much higher than the 
concentrations of CH3COO- + H+.
C. It never reaches equilibrium.
D. It is spontaneous, starting with CH3COOH.
E. The equilibrium constant increases when the starting concentration of CH3COOH 
is increased

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96. The hydrophobic cleft in globular proteins which bind substrate molecules is called
A. The substrate pocket
B. The modulator site
C. The active site
D. The activity site
E. * The oligomeric site
97. The inactive precursor of an active enzyme is called
A. Zymogen
B. Ribozyme
C. Isozyme
D. * Abzyme
E. Nucleozyme
98. The inhibition of succinate dehydrogenase by malonate is an example for
A. * Competitive inhibition
B. Non competitive inhibition
C. Uncompetitive inhibition
D. Feedback or end product inhibition
E. None of these
99. The initial velocity assumption for Michaelis-Menton kinetic assumes that ______.
A. * The reaction is always running at Vmax.
B. The rate of E + P -> ES is negligible.
C. A large amount of product has formed.
D. K-2 is large.
E. None of the above.
100. 
The initial velocity assumption of the Michaelis-Menton equation states that 
__________.
A. * The rate of ES formation is equal to the rate of ES turnover
B. A large amount of product is formed
C. The rate of the P T ES reaction is negligible
D. a and b
E. b and c
101. 
The ions of what metal contain porphirine coenzymes?
A. Na
B. * Fe
C. Zn
D. Mo
E. Mn
102. 
The low value of Km indicates
A. High enzyme activity
B. High substrate affinity of enzyme
C. No effect on reaction
D. * Low affinity of enzyme with substrate
E. All of these
103. 
The mechanism of enzyme action is _____.
A. To create an energy barrier between substrates
B. To lower the energy of the activation of a reaction
C. * To change the direction of thermodynamic equilibrium
D. To change endergonic into exergonic reactions
E. To allow substrates to move more freely in solution
104. 
The non protein compound that acts as enzyme is
A. * DNA
B. RNA

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C. Carbohydrate
D. Fat
E. Vitamins
105. 
The noncompetitive inhibitor
A. Increases Vmax and Km
B. * Decreases Vmax
C. Increases Km without affecting Vmax
D. Decreases Km and Vmax
E. Increases Km
106. 
The product(s) of lactate dehydrogenase under anaerobic conditions is (are)
A. Pyruvic acid
B. NAD+
C. NADH
D. A and b
E. * A and c
107. 
The relationship between an enzyme and a reactant molecule can best be 
described as:
A. A temporary association
B. An association stabilized by a covalent bond
C. * One in which the enzyme is changed permanently
D. A permanent mutual alteration of structure
E. Noncomplementary binding
108. 
The role of zinc in the mechanisms of carbonic anhydrase is to
A. Maintain the configuration of the holoenzyme
B. Bind to three histidine residues
C. Produce a nucleophilic attack on the substrate
D. * Promote ionization of bound water
E. Produce an electrophilic attack on the substrate
109. 
The rules are for each half-reaction:
A. Balance all elements except hydrogen and oxygen.
B. Balance oxygen by adding water (H2O(l)).
C. Balance hydrogen by adding H+(aq) ion
D. * Balance charge by adding electrons
E. Increase speed of reaction
110. 
The specific activity of an enzyme is
A. The amount of enzyme that produces one mole of product per second under 
standard conditions
B. The activity of an enzyme in relation to a standard preparation of the enzyme
C. The number of enzyme units per milligram of enzyme protein
D. * The activity of an enzyme in the presence of its preferred substrate
E. All of above
111. 
The term given to the number of substrate molecules an enzyme can process per 
second –
A. Reaction rate
B. * Michaelis constant
C. Optimal rate
D. Turnover rate
E. The substrate processing number
112. 
The transition state of a catalyzed reaction (EX‡) is
A. * A highly-populated intermediate on the reaction pathway
B. Higher in energy than that of an uncatalyzed reaction
C. Lower in energy than that of an uncatalyzed reaction

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D. Lower in energy than the reaction substrate
E. Bound very weakly to the catalyst
113. 
The typical saturation curve for an enzyme catalyzed reaction is sigmoidal. This 
indicates that the enzyme is
A. * A regulatory enzyme
B. A nonregularoty enzyme
C. Both
D. None
E. All of above
114. 
The uncompetitive inhibitor binds with
A. Active site
B. Allosteric site
C. * Enzyme substrate complex
D. Substrate
E. Product of reaction
115. 
Trypsin is a
A. * Exopeptidase
B. Endopeptidases
C. Carboxy peptidase
D. Phosphotransferase
E. Phosphopeptidase
116. 
Unlike typical catalyzed reactions in organic chemistry enzyme reactions are
A. Usually stereospecific
B. Reaction specific
C. Essentially 100% efficient
D. Modulated to change activity levels.
E. * All of the above.
117. 
Vmax ______________________.
A. Describes the velocity of reaction when substrate is bound to ? of the available 
substrate binding sites on an enzyme
B. * Describes the velocity of reaction when all of the available substrate binding 
sites on an enzyme are occupied by substrate
C. Is a rate constant for the reaction where the ES complex is converted to the E +
D. Is the value equal to one over the x intercept of a Lineweaver Burk plot.
E. B and d
118. 
What component is not included in the structure of holoenzymes?
A. Apoenzyme
B. Coenzyme
C. Cofactor
D. Prostetic group
E. * Izoenzyme
119. 
What distinguishes reversible inhibitors from irreversible inhibitors?
A. Reversible inhibitors are not covalently bound to enzymes but irreversible 
inhibitors are.
B. There is an equilibrium between bound and unbound reversible inhibitor. There 
usually is little back reaction for the binding of an irreversible inhibitor.
C. Reversible inhibitors are easier to purify from solutions of enzymes than 
irreversible inhibitors.
D. * All of the above.
E. a and b only.
120. 
What does appear common for enzymes with relative specificity?
A. * Action on the identical type of bonds of certain group of substrates

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B. Ability to convert one substrate
C. Ability to influence on D - isomers
D. Influence on D- isomers, but does not influence on L- isomers
E. Action on a few types of bonds of certain group of substrates
121. 
What feature is not commonly for all izoenzymes?
A. Action on the one substrate
B. Catalysis of identical reactions
C. Finding in different tissuers
D. * Electrophoretic mobility
E. Izoenzymes is typical for most enzymes, that in the structure have a few subunits
122. 
What is the area of an enzyme called where the chemical reactions occur?
A. The Cytoplasm
B. * The Active Site
C. The Catalyst
D. The Nucleus
E. A substrate
123. 
What method was the presence in the first time set by izoenzymes?
A. Dialysis
B. * Elektroforezis in the starched gael
C. Chromatography
D. Centrifugation
E. Rengen analysis
124. 
What structure of proteins molecule is responsible for formation of active centre 
and for his catalytic action?
A. Primary
B. * Tertiary
C. Secondary
D. Quaternary
E. None from following
125. 
When considering the features of an exergonic reaction, exergonic reactions:
A. * Release energy
B. Are spontaneous reactions
C. Have an equilibrium constant greater than 1
D. Can be coupled to energonic reactions
E. All statements are true.
126. 
When you plot [S] versus initial velocity for an allosteric enzyme, what type of 
plot arises?
A. * Hyperbolic
B. Sigmoidal
C. Linear
D. Discontinuous
E. Exponential
127. 
Which aminoacids residues does not enter in the composition of active center of 
enzyme?
A. Serine
B. Cystein
C. Histidin
D. Thyrosin
E. * Arginine
128. 
Which coenzyme is covalently bound to the enzyme active site?
A. NAD+/NADH
B. * Lipoamide

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C. Coenzyme A
D. None of the above
E. Biotin
129. 
Which coenzyme is likely involved in the reaction shown below?
A. * TPP
B. Biotin
C. Coenzyme A
D. FMN
E. NAD
130. 
Which coenzyme links to a lysine residue in a protein's active site?
A. Biotin
B. Lipoic acid (lipoamide)
C. Pyridoxal phosphate
D. Biotin and pyridoxal phosphate only
E. * All three; biotin, lipoic acid and pyridoxal phosphate
131. 
Which commonly involve some sort of mineral or metal?
A. Ligands and binding sites
B. Cofactors and prosthetic groups
C. * Coenzymes and cofactors
D. Ligands and prosthetic groups
E. Nasty scraping sounds
132. 
Which enzymes do not enter in the complement of porphirine coenzymes?
A. Cytochrome b, с
B. Catalase
C. Peroxidase
D. * Phosphatase
E. Cytochrome а1, а
133. 
Which of the following best describes the ability of an enzyme to convert the ES 
complex to E + P?
A. * Vmax
B. Km
C. Kcat
D. Kcat/Km
E. All of the above
134. 
Which of the following coenzymes functions in acyl transfer reactions?
A. NADPH
B. * Coenzyme A
C. Biotin
D. A and b
E. B and c
135. 
Which of the following coenzymes participates in enzymatic mechanisms by 
producing a free radical intermediate?
A. NADPH
B. Ubiquinone
C. Methylcobalamin
D. Biotin
E. * Lipoamide
136. 
Which of the following is a property of a catalyst?
A. A catalyst can alter the equilibrium of a chemical reaction.
B. A catalyst is changed to a different form at the end of a reaction.
C. * A catalyst can increase the rate of a chemical reaction.
D. a and c

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E. all of the above
137. 
Which of the following is best used to determine how well a specific substrate is 
used by a specific enzyme?
A. Km
B. * kcat
C. Vmax
D. kcat/ Km
E. ? Vmax
138. 
Which of the following is true of enzymes that are regulated by allosteric 
regulation?
A. * They are usually multimeric enzymes
B. A hyperobolic curve results from the plotting of Vo vs [S]
C. They behave according to Michaelis-Menton kinetics
D. A and b
E. B and c
139. 
Which of the following kinetic parameters best describes the ability of a specific 
substrate to bind to a specific enzyme?
A. Vmax
B. Km
C. Kcat
D. Kcat/Km
E. * All of the above
140. 
Which of the following statements is FALSE?
A. Enzymes make reactions 103 to 1017 times faster.
B. Enzymes lower the amount of energy needed for a reaction.
C. * Enzymes are unchanged during a reaction.
D. Enzymes speed up the attainment of a reaction equilibrium.
E. Enzymes are proteins.
141. 
Which of the following types of reactions will result in a hyperbolic plot when [S] 
is plotted versus initial velocity?
A. Allosterically regulated reactions
B. Multi-step reactions
C. * Michaelis Menton reactions
D. A and c
E. All of the above
142. 
?Which of the statements regarding enzymes is false?
A. Enzymes are proteins that function as catalysts
B. Enzymes are specific
C. * Enzymes provide activation energy for reactions
D. Enzyme activity can be regulated
E. Enzymes may be used many times for a specific reaction
143. 
Which of these phrases best describes how enzymes affect chemical reactions?
A. Lower the activation energy
B. Raise the activation energy
C. * Supply activation energy
D. Remove activation energy
E. Could it have something to do with activation energy.?
144. 
Which of these statements about enzyme inhibitors is true?
A. * A competitive inhibitor binds to the enzyme outside the active site.
B. The action of competitive inhibitors may be reversible or irreversible.
C. A noncompetitive inhibitor does not change the shape of the active site.

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D. When the product of an enzyme or an enzyme sequence acts as its inhibitor, this 
is known as positive feedback
E. Antibiotics and pesticides generally do not act on enzymes, but rather affect the 
genetic code of their victims
145. 
Which of these statements about enzyme inhibitors is true?
A. * A competitive inhibitor binds to the enzyme outside the active site
B. The action of competitive inhibitors may be reversible or irreversible
C. A noncompetitive inhibitor does not change the shape of the active site
D. When the product of an enzyme or an enzyme sequence acts as its inhibitor, this 
is known as positive feedback.
E. Antibiotics and pesticides generally do not act on enzymes, but rather affect the 
genetic code of their victims.
146. 
Which one of the following is an example of the second law of thermodynamics?
A. The aerobic respiration of glucose generates heat.
B. * All types of cellular respiration produce ATP.
C. CO2 is exhaled as a by-product of aerobic respiration.
D. Photosynthesis enables plants to create energy from sunlight.
E. Energy is stored during the Calvin cycle.
147. 
Which statement about enzyme catalyzed reactions is NOT true?
A. Enzymes form complexes with their substrates
B. Eenzymes lower the activation energy for chemical reactions.
C. Eenzymes change the Keq for chemical reactions.
D. * Many enzymes change shape slightly when substrate binds.
E. Reactions occur at the "active site" of enzymes, where a precise 3D orientation of 
amino acids is an important feature of catalysis
148. 
Which statement about enzyme catalyzed reactions is NOT true?
A. Enzymes form complexes with their substrates
B. Enzymes lower the activation energy for chemical reactions
C. Enzymes change the K eq for chemical reactions
D. Many enzymes change shapes slightly when substrate binds
E. * Reactions occur at the "active site" of enzymes, where a precise 3D orientation 
of amino acids is an important feature of catalysis
149. 
Which statement regarding enzyme function is true?
A. * Higher temperatures allow greater contact between enzymes and substrates; 
therefore, the higher the temperature the better the enzyme will function.
B. Enzymes cannot function at a pH lower than 6.
C. Most coenzymes are inorganic substances such as ions of iron or potassium.
D. Excessive salt ions can cause an enzyme to denature.
E. All of the above.
150. 
Which statement regarding enzyme function is true?
A. Higher temperatures allow greater contact between enzymes and substrates; 
therefore, the higher the temperature the better the enzyme will function.
B. Enzymes cannot function at a pH lower than 6.
C. Most coenzymes are inorganic substances such as ions of iron or potassium.
D. Excessive salt ions can cause an enzyme to denature.
E. * All of the above.
151. 
Which type of regulation occurs in the slowest time frame?
A. Regulation through covalent modification
B. Allosteric regulation
C. New synthesis of enzyme through gene induction
D. * Feedback regulation
E. None of the above

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152. 
Which type of specificity of enzymes does not existence?
A. Relative
B. Absolute
C. * Conformation
D. Space specificity
E. Stereospecificity
153. 
Which vitamins does not appear as coenzymes?
A. B1
B. B2
C. B5
D. * С
E. B12
154. 
Which would most likely not have much stereospecificity?
A. * Antibodies
B. Receptors
C. Enzymes
D. Codons
E. People who buy their components at Wal-Mart
155. 
Why does heating interfere with the activity of an enzyme?
A. It kills the enzyme
B. It changes the enzyme’s shape
C. It decreases the energy of substrate molecules
D. * It causes the enzyme to break up
E. It decreases the chance that the enzyme will meet a substrate molecule
156. 
Zinc is present in which of the following enzymes
A. Cytochrome oxidase
B. Arginase
C. Hexokinase
D. * Alcoholdehydrogenase
E. Catalase
157. 
A 37 years old man was delivered to the hospital with symptoms of sharp 
pancreatitis: vomiting, diarrhea, bradicardia, hypotension, weakness, dehydration of 
organism. What preparation should be used for the treatment?
A. Ephedrine
B. * Kontrikal
C. Platifilin
D. No-spa
E. Etaperazin
158. 
A 45 years old patient suffers from pain in lumbar department of the back and its 
limited mobility. It is takes place darkening of urine with air. What inherited disease has 
the patient?
A. Phenylketonuria
B. Galactosemia
C. * Alkaptonuria
D. Cystinosis
E. Syndrome of Fankoni
159. 
A 45 years old patient suffers from pain in lumbar department of the back and its 
limited mobility. It is takes place darkening of urine with air. What inherited disease has 
the patient?
A. Phenylketonuria
B. Galactosemia
C. * Alkaptonuria

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D. Cystinosis
E. Syndrome of Fankoni
160. 
A 46 years old woman appealed to the doctor with complaints about pain in the 
epigastrium after the fatty meal. Doctor suspected acute pancreatitis. Content of which 
from the transferred substances in blood increased at this pathology?
A. Glucose
B. Aspartate amino transferase
C. Alanine amino transferase
D. * Amylase
E. Calcium
161. 
A 47-years-old man was delivered to the hospital with the diagnosis – 
myocardium infarction. What factions of LDH will prevail in the blood serum during the 
first two days of disease?
A. LDH3
B. LDH2
C. * LDH1
D. LDH4
E. LDH5
162. 
A 60-years-old man appealed to the doctor with complains of pain in a thorax. In 
the blood serum were established increase of such enzymes activity: MB isoforms of 
creatin phospho kinase, aspartate amino transpherase. About development of pathological 
process in what organ or tissue do these changes testify?
A. In lungs
B. * In cardiac muscle
C. In skeletal muscles
D. In the liver
E. In smooth muscles
163. 
A blood test was done in a biochemical laboratory with the diagnostic purpose for 
a patient with the early stage of muscular dystrophy. Increase of activity of what enzyme 
can be observed in this case?
A. Alanine aminotransferase
B. * Creatin kinase
C. Collagenase
D. Hyaluronidase
E. Glutaminase
164. 
A child was delivered to a reanimation with such symptoms: vomit, diarrhea, 
abnormal physical and mental development, cataract. Laboratory test showed 
galactosemia. The deficiency of what enzyme does take place?
A. Galactokinase
B. UDP glucose-4-epimerase
C. * Hexose-1-phosphate-uridiltransferase
D. UDP- glucose –pyrophosphorilase
E. Glucose-6-phosphate dehydrogenase.
165. 
A new-born child has diarrhea, vomiting and cataract. Disorder of synthesis of 
what enzyme causes this disease?
A. * Galactose – 1 – phosphate uridyl transpherase
B. Glucose - 6 phosphatase
C. Hexokinase
D. Glycogen synthase
E. Glucose phosphate isomerase
166. 
A new-born child has diarrhea, vomiting and cataract. Disorder of synthesis of 
what enzyme caused this disease?

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A. * Galactose – 1 – phosphate uridyl transpherase
B. Glucose - 6 phosphatase
C. Hexokinase
D. Glycogen synthase
E. Glucose phosphate isomerase
167. 
A newborn suffers from the fatty degeneration of liver, takes place a galactosuria 
and amino aciduria, increased level of total bilirubin in blood. What matter is it necessary 
to exclude from the diet of child?
A. * Lactose
B. Fatty acids
C. Phenylalanine
D. Cholesterol
E. Saccharose
168. 
A patient complains about acute stomach-ache, nausea, vomitting. Diastase 
activity is 800 grammes/l hour What diagnosis is the most possible?
A. Acute cholecystitis
B. * Acute pancreatitis
C. Ulcer of stomach
D. Acute appendicitis
E. Enterocolitis
169. 
A patient complains about acute stomach-ache, nausea, vomit. Diastase activity is 
800 grammes/l•hour What diagnosis is the most possible?
A. Acute cholecystitis
B. * Acute pancreatitis
C. Ulcer of stomach
D. Acute appendicitis
E. Enterocolitis
170. 
A patient complains about pain on the left side in breast, weakness and 
tachycardia. What from the transferred enzymes is it necessary to define in blood for 
confirmation of diagnosis of heart attack of myocardium?
A. * AsAT, CPK MB, LDH-1
B. AlAT, aldolase, LDH-4
C. Amylase, alkaline фосфатаза, ALAT
D. Acidic phosphatase, LDH-5, LDH-4
E. fetoprotein, aldolase, CK
171. 
A patient has disorder of liver functions. Which from the below mentioned 
biochemical indexes in blood is used for the estimation of the liver state?
A. * AlAT
B. LDH1
C. Creatin phosphokinase
D. Aldolase
E. Lipase
172. 
A patient has metabolic acidosis. How will it change activity of intracellular 
enzymes?
A. Activity of intracellular enzymes do not change substantially.
B. Activity of mitochondrial enzymes increased, activity of lysosomal enzymes 
inhibited, which is accompanied the decline of catalytic processes
C. * Activity of mitochondrial enzymes is low, activity of lysosomal enzymes, which 
will result in strengthening of catalytic processes, is increased
D. Total inhibition of all of tissue enzymes
E. Total activating of all of tissue enzymes

---

173. 
A patient has metabolic acidosis. How will it change activity of intracellular 
enzymes?
A. Activity of intracellular enzymes does not change substantially
B. Activity of mitochondrial enzymes increases, activity of lysosomal enzymes 
inhibits, which is accompanied the decline of catalytic processes
C. * Activity of mitochondrial enzymes is low, activity of lysosomal enzymes, which 
will result in strengthening of catalytic processes, is increased
D. Total inhibition of all of tissue enzymes
E. Total activating of all of tissue enzymes
174. 
A patient is found to be deficient in the enzyme galactose 1-phosphate 
uridylyltransferase. Specifically due to this deficiency what might a doctor recommend?
A. avoid all strenuous exercise
B. eat a fat-free diet
C. increase intake of vitamin C
D. * avoid ingestion of milk and milk products
E. all of the above.
175. 
A patient was delivered to a hospital. Possible diagnosis - acute pancreatitis. The 
increase of activity of what enzyme can prove this disease?
A. Creatin kinase
B. Pepsin
C. Gastrixin
D. * Amylase
E. Aspartate transaminase
176. 
A specific test on the damage of kidneys tissues for the proof of diagnosis - 
inflammatory process in kidneys of the patient was conducted. This test is determination 
in urine:
A. Concentrations of creatin
B. Activity of creatin phosphokinase MB
C. Presence of lactose
D. * Activity of transamidinase
E. Activity of pepsin
177. 
A two years old child was delivered to the hospital with symptoms of mental and 
physical underdevelopment, which suffers from the frequent vomiting after meal. In urine 
found out phenyl-pyruvic acid. Disorder of which substances metabolism is this 
pathology?
A. Phosphorus-calcium metabolism
B. Water-salt metabolism
C. * Metabolism of amino acids
D. Carbohydrates metabolism
E. Lipids metabolism
178. 
A two years old child was delivered to the hospital with symptoms of mental and 
physical underdevelopment, which suffers from the frequent vomiting after meal. In urine 
found out phenyl-pyruvic acid. Disorder of which substances metabolism is this 
pathology?
A. Phosphorus-calcium metabolism
B. Water-salt metabolism
C. * Metabolism of amino acids
D. Carbohydrates metabolism
E. Lipids metabolism
179. 
Acute pancreatitis of the patient was diagnosed. Determination of which from the 
below mentioned enzymes in blood can be a diagnostic criteria?
A. LDH

---

B. Aldolase
C. * Amylases
D. Creatin kinase
E. Alanine amino peptidase
180. 
Acute pancreatitis was diagnosed after biochemical analyses. In order to avoid 
autolysis of pancreas it is necessary to apply such preparations:
A. Complex of pancreatic enzymes
B. Insulin
C. * Inhibitors of proteolytic enzymes
D. Antibiotics
E. Sulfanilamides
181. 
An acute pancreatitis and parotitis are diagnosed. How will it influence on the 
activity of amylase in urine?
A. * High activity of amylase is in urine.
B. Low activity of amylase is in urine.
C. No any of amylase in urine.
D. No any changes.
E. All answers are correct.
182. 
An acute pancreatitis and parotitis are diagnosed. How will it influence on the 
activity of amylase in urine?
A. * High activity of amylase is in urine
B. Low activity of amylase is in urine
C. No any of amylase in urine
D. No any changes
E. All answers are correct.
183. 
At an inspection In blood of the patient was found increase of enzymes activity: 
creatin kinase, AsAT and LDH1, 2. What diagnosis is it possible in this case?
A. Muscular dystrophy
B. * Infarction of myocardium
C. Cirrhosis of liver
D. Disorders of CNS
E. Pancreatitis
184. 
At the inspection of patient was diagnosed alkaptonuria. The deficiency of what 
enzyme causes this pathology?
A. * Oxidase of homogentisic acid
B. Phenylalanine hydroxylase
C. Thyrosinase
D. Thyroxin hydroxylase
E. Mono amino oxidase
185. 
At the inspection of patient was diagnosed alkaptonuria. The deficiency of what 
enzyme causes this pathology?
A. * Oxidase of homogentisic acid
B. Phenylalanine hydroxylase
C. Thyrosinase
D. Thyroxin hydroxylase
E. Mono amino oxidase
186. 
At the inspection of patient was found an increase of LDH activity in blood. It is 
possible at the diseases of heart, liver, kidneys. What additional biochemical test should 
be done for proper diagnostics?
A. Determination of sugar is in blood
B. * Determination of isoforms of LDH
C. Determination of ketone bodies level in blood

---

D. Determination of cholesterol level in blood
E. Determination of amylase in blood
187. 
At treatment of bleeding wounds with a 3% hydrogen peroxide there forms a foam 
due to decomposition of hydrogen peroxide with enzyme of blood. Choose this enzyme:
A. Monoaminooxidase
B. Carboanhydrase
C. Cytochromoxidase
D. * Catalase
E. Lactate dehydrogenase
188. 
At treatment of bleeding wounds with a 3% hydrogen peroxide there forms a foam 
due to decomposition of hydrogen peroxide with enzyme of blood. Choose this enzyme:
A. Monoaminooxidase
B. Carboanhydrase
C. Cytochromoxidase
D. * Catalase
E. Lactate dehydrogenase
189. 
Cardiac muscle contains which of the following CK isoenzyme?
A. BB only
B. MM and BB only
C. MM, BB and MB
D. * MM and MB only
E. None of the above
190. 
Diastase can be used for the hydrolysis can be used for the hydrolysis of
A. Sucrose
B. * Starch
C. Cellulose
D. Maltose
E. None of the above
191. 
Enzymes of amnion liquid of 28 years old pregnant women weredetermined. 
Insufficient activity of glucuronidase was detected. What pathological process is 
possible?
A. Glycogenosis
B. * Mucopolysacharidosis
C. Aglycogenosis
D. Collagenosis
E. Lipidosis
192. 
estimation will have the best predictive value?
A. Serum AST
B. Serum CK
C. Serum ALT
D. * Serum LDH
E. All of the above
193. 
Festering wound was washed a with a hydrogen peroxide, but foam did not 
appear. The possible reason of it is:
A. * Inherent absence of catalase
B. Too match of the rot in a wound
C. Small wound
D. A lack of iron in an organism
E. Lack of peroxydase
194. 
For 18 years old patient with acute toxic hepatitis in the blood serum will be 
enhanceable level:
A. * Alaninaminotransferase

---

B. Creatinkinase
C. Alkaline phosphatase
D. D-amilase
E. Lactate dehydrogenase-1 (LDH1)
195. 
For a child which borned 2 days ago, observe the yellowing colour of skin and 
mucus shells. Reason of such state can be a lack of enzyme:
A. * UDP-glyucuroniltransferase
B. Sulphontransferase
C. Hemshyntetase
D. Hemoxigenase
E. Biliverdinreductase
196. 
For cleaning of festering wound and their rapid healing used immobilized trypsin 
on bandaging material. What it advantage as for the native enzyme?
A. * Long term of action
B. Higher activity
C. Higher specificity of action
D. Higher sensitivity to the temperature
E. Higher sensitivity to the changes of рН
197. 
For cleaning of festering wound pharmaceutical enzymes preparations are used. 
Specify what matter will be effective for cleaning from necrotizing tissues and wounds 
healing :
A. Washing with glucose oxidase
B. * Applications with Trypsin
C. Washing with a hydrogen peroxide
D. Imposition of sterile bandages
E. Imposition of bandages with NaCl
198. 
For diagnostic of acute inflammatory process in kidneys was conducted a specific 
test - determination in urine of such substance:
A. Content of lactose
B. Activity of creatinkinase
C. Concentrations of creatin
D. Activity of pepsin
E. * Activity of alanine amino peptidase
199. 
For dissolving of scars, compressions, hematomas, the easier transport of 
medications in tissues such enzyme is used:
A. Trypsin
B. Ribonuclease
C. * Hyaluronidase
D. Plasmin
E. Pepsin
200. 
For the patient with respiratory infection sulphanylamide preparation 
(sulphodimetoxin) was recommended. What mechanism of action of this preparation:
A. * Competitive inhibition of enzymes of folic acid formation from Para-amino 
benzoic acid of microorganisms
B. Inhibition of translation of bacterial proteins.
C. Noncompetitive inhibition of viral cytochrome oxydase.
D. Inhibition of transcription initiation
E. Irreversible inhibition of viruses replication.
201. 
For treatment of dermatitises, wounds and ulcers which heal badly are used 
coenzyme preparations of flavin mononucleotide and flavinate. The active forms of 
which vitamin are they?
A. B1

---

B. * B2
C. B5
D. B3
E. C
202. 
For treatment of dermatitises, wounds and ulcers which heal badly used 
coenzymes preparations of flavin mononucleotide and flavinate. The active forms of 
what vitamin are they?
A. * B2
B. B1
C. B5
D. B3
E. C
203. 
For treatment of the patient with acute pancreatitis a doctor prescribed a trasilol. 
For what purpose used this preparation?
A. * To avoid of autolysis of pancreas
B. For the improvement of fats digestion
C. For the improvement of proteins digestion
D. For the increase of insulin secretion
E. All above are correct
204. 
From the human blood serum were selected and discovered properties of five 
isoenzyme forms of lactate dehydrogenase. What property of isoenzyme does prove that 
the selected forms are the same enzyme?
A. Same molecular mass
B. * Catalyze the same reaction
C. Same physical and chemical properties
D. Tissue localisation
E. Same electrophoretic mobility
205. 
Hairs, skin and eyes of a patient do not have a pigment. A diagnosis – albinism 
was set. The deficiency of what enzyme does take place?
A. * Tyrosinase
B. Arginase
C. Carbanhydrase
D. Histidin decarboxylase
E. Aldolase
206. 
In a stomach of new-born takes place transformation of soluble of milk proteins - 
caseins into insoluble protein - paracasein with participation of calcium ions and enzyme. 
What enzyme does take part in this process?
A. * Rennin
B. Pepsin
C. Gastrin
D. Secretin
E. Lipase
207. 
In an organism was found the lack of iron. It will cause the decrease of such 
enzyme activity:
A. Glutation peroxidase
B. Carboanhydrase
C. Carboxypeptidase
D. Ceruloplasmin
E. * Catalase
208. 
In an organism was found the lack of copper. It will cause the decrease of such 
enzyme activity:
A. Cytochrome b

---

B. Glucose oxidase
C. Catalase
D. * Cytochrome oxsidase
E. Glutation peroxidase
209. 
In blood and urine of a patient it was takes place increase value of pyruvic and 
ketoglutaric acids. The deficiency of which coenzyme causes these changes?
A. Pyridoxal phosphate
B. * Thiamin pyrophosphate
C. Flavin mononucleotide
D. Biotin
E. Ubiqinon
210. 
In blood and urine of a patient it was takes place increase value of pyruvic and ?-
ketoglutaric acids. The deficiency of which coenzyme causes these changes?
A. Pyridoxal phosphate
B. * Thiamin pyrophosphate
C. Flavin mononucleotide
D. Biotin
E. Ubiqinon
211. 
In blood of a patient were found out the decline of activity of amino transferases 
and decarboxylases of amino acids. Which coenzyme preparation may be recommended 
for this patient?
A. Thiamin pyrophosphate
B. FAD
C. * Pyridoxal phosphate
D. NAD
E. Ubiqinon
212. 
In blood of patient found out the increase of activity of LDH1, LDH2, AsAT, 
creatin phosphokinase - MB. In what organ disorders of biochemical processes takes 
place?
A. Pancreas
B. Skeletal muscles
C. Kidneys
D. Liver
E. * Heart
213. 
In bloodof the patient concentration of acetaldehyde is increased, and causes 
disgust of an alcohol. What preparation - the inhibitor of aldehyde dehydrogenase is used 
in medical practice for the prophylaxis of alcoholism?
A. Ethanol.
B. * Teturam.
C. Trasilol
D. Aldehyde
E. Methanol
214. 
In medical practice for treatment of festering wound enzymes preparations are 
used. Which from the below mentioned enzymes is used in such cases?
A. * Trypsin
B. Alkaline phosphatase
C. Acidic phosphatase
D. Amylase
E. Arginase
215. 
In poison of some snakes there is an enzyme which in a human organism can 
result in formation of substances with a hemolytic action. Choose it.
A. * Phospho lipase A2

---

B. Lipase A1
C. Lipase C
D. Phospho lipase D
E. Phospho lipase B
216. 
increase in which of the LDH isoenzyme fraction?
A. LDH-1
B. LDH-1 and LDH-2
C. * LDH-3 and LDH-4
D. LDH-2 and LDH-3
E. LDH-5
217. 
It was determinate high activity of amylase in a patient’s saliva . How properly 
interpret this analysis?
A. * ParotitisIt is possible.
B. Pathology of liver.
C. This analysis testifies disorders of gastrointestinal tract.
D. It is possible at nephropathies
E. This analysis testifies disorders of carbohydrate metabolism in an organism.
218. 
It was determinate high activity of amylase in urine of a patient. How properly 
interpret this analysis?
A. * It is possible acute pancreatitis, parotitis.
B. Pathology of liver.
C. This analysis testifies disorders of gastrointestinal tract.
D. It is possible at nephropathies
E. This analysis testifies disorders of carbohydrate metabolism in an organism.
219. 
It was determine high activity of amylase in urine of a patient. How properly 
interprete this analysis?
A. * It is possible acute pancreatitis, parotitis.
B. Pathology of liver.
C. This analysis testifies disorders of gastrointestinal tract.
D. It is possible at nephropathies
E. This analysis testifies disorders of carbohydrate metabolism in an organism.
220. 
It was established that at parodontitis the secretion of kallikrein is increased. 
Choose, what does increase inflammatory reaction in an oral cavity as result the of this 
enzyme action?
A. Trasilol
B. * Kinins
C. Secretory immunoproteins
D. Lysozyme
E. Factor of nerves growth
221. 
New antibiotics are synthesized with fermentative transformations of natural 
antibiotics. What from the below named forms of enzymes are widely used in 
pharmaceutical industry?
A. * Immobilized enzymes
B. Native enzymes
C. Denaturized enzymes
D. Complex of enzyme with a coenzyme
E. Complex of enzyme with an activator
222. 
On which day following acute myocardial infarction the estimation of serum AST 
willbe of greatest significance?
A. First day
B. * Second day
C. Third day

---

D. Fourth day
E. None of the above
223. 
Organism suffers from hypovitaminosis of B5. How will it change the function of 
oxidoreductases?
A. It will inhibit synthesis and functions of cytochroms
B. It will inhibit synthesis and functions of FMN and FAD – dependent 
dehydrogenases
C. It causes improper synthesis and functions of TPP, which is the coenzyme of 
pyruvate dehydrogenase.
D. It causes inhibition of synthesis and functions of aminotransferases.
E. * It causes inhibition of synthesis and functions of NAD and NADP – dependent 
oxidoreductases (dehydrogenases)
224. 
Parotitis of the patient was diagnosed. Determination of which from the below 
mentioned enzymes in blood can be a diagnostic criteria?
A. LDH
B. Aldolase
C. * Amylases
D. Creatin kinase
E. Alanine amino peptidase
225. 
released in plasma?
A. Kidney, R.B.C and Liver
B. * Heart, Kidney and R.B.C
C. Heart, Kidney and Liver
D. Heart, Lungs and Brain
E. All of the above
226. 
Salivary amylase is an enzyme in humans that breaks down starch. The optimum 
pH for this reaction is 6.7. The rate of this reaction would not be affected by
A. * Maintaining the pH of the reaction at 6.7
B. Substrate concentration
C. Enzyme concentration
D. Decreasing the temperature of the reaction by 5oC
E. Maintaining the pH of the reaction at 7.7
227. 
Teturam which is the inhibitor of aldehyde dehydrogenase used in medical 
practice for the prophylaxis of alcoholism. An increase in blood of what metabolite 
causes disgust of an alcohol?
A. malonic aldehyde
B. Ethanol
C. * Acetaldehyde
D. Proponic aldehyde
E. Methanol
228. 
The analysis demonstrated a 10 times increase of diastase activity. The danger of 
autolysis of a patient’s pancreas caused with activating of enzyme:
A. Amylase
B. Pepsin
C. * Trypsin
D. Lipase
E. Nuclease
229. 
The analysis demonstrated a 10 times increase of diastase activity. The danger of 
autolysis of a patient’s pancreas caused with activating of enzyme:
A. Amylase
B. Pepsin
C. * Trypsin

---

D. Lipase
E. Nuclease
230. 
The functional state of liver, effectiveness of treatment and prognosis of disease 
development, estimate by such biochemical indexes of blood and urine, except:
A. AlAT
B. Gamma-glutamintranspeptidase
C. Alkaline phosphatase
D. Contents of albumins and globulins
E. * Diastase
231. 
?The inherited genetic defects result in violation of synthesis of some enzymes in 
the human organism. The defect of which enzyme results in disorders of splitting of 
lactose:
A. * Lactase
B. Maltase
C. Sucrase
D. Amylase
E. Peptidase
232. 
The patient with cyanide poisoning was delivered to clinic. What mast be 
immediately used for the improvement of his state?
A. Glucose
B. Ascorbic acid
C. * Cytochromoxidase
D. Vitamin B1
E. Nicotine amide
233. 
The рН of children’s gastric juice is of 4,0-5,0. Name the enzyme of gastric juice 
which is active in this conditions.
A. * Rennin
B. Pepsin
C. Trypsin
D. Elastase
E. Chymotrypsin
234. 
Trypsin
A. * Arginase
B. Catalase
C. Alkaline phosphatase
D. Acidic phosphatase
235. 
Viral hepatitis of a 5 years old child is suspected. Which from below mentioned 
indexes is it necessary to define for confirmation of diagnosis?
A. LDH2
B. LDH1
C. AsAT
D. * AlAT
E. Creatin kinase
236. 
Vomiting, diarrhea after consuming milk, enlargement of the liver, jaundice, 
cirrhosis,cataracts, retardation of the mental development, elevated blood-galactose level, 
absence of the galactose 1-phosphate uridyl transferase in red blood cells are the 
symptoms of:
A. lactose intolerance
B. hypolactasia
C. * galactosemia
D. all of the above
E. diabetes mellitus

---

237. 
With ageing in cartilaginous decreases intensity of proteoglycans formation that 
leads to diminishing of degree of their hydratation and loss of tissues turgor. Activity of 
what enzymes of lysosomes does increase?
A. Deaminase, decarboxylase
B. Isomerase, dehydrogenases
C. Protease, lipase
D. Oxidoreductases, phosphstase
E. * Cathepsins, glycosidase
238. 
With urine of newborn was done a reaction with FeCI3 and a positive reaction 
(dark color) got. What disease is possible?
A. Galactosemia
B. Tirosinosis
C. * Phenylketonuria
D. Alkaptonuria
E. Aminoaciduria.
239. 
With urine of newborn was done a reaction with FeCI3 and a positive reaction 
(dark color) got. What disease is possible?
A. Galactosemia
B. Tirosinosis
C. * Phenylketonuria
D. Alkaptonuria
E. Aminoaciduria
240. 
A reaction can occur spontaneously only if G, the change in free energy of 
products and reactants, is:
A. positive;
B. * negative;
C. 0;
D. all reactions can occur spontaneously.
E. all of the above.
241. 
All of the following compounds are intermediates of TCA cycle except
A. Malate
B. * Pyruvate
C. Oxaloacetate
D. Fumarate
E. ?-Ketoglutarate
242. 
An aneplerotic reaction which sustains the availability of oxaloacetate is the 
carboxylation of
A. Glutamate
B. * Pyruvate
C. Citrate
D. Succinate
E. All of the above
243. 
If all the enzymes, intermediates and cofactors of the citric acid cycle as well as 
an excess of the starting substrate acetyl-CoA are present and functional in an organelle 
free solution at the appropriate pH, which of the following factors of the citric acid cycle 
would prove to be rate limiting?
A. Molecular oxygen
B. Half life of enzyme
C. Turnover of intermediates
D. * Reduction of cofactors
E. All of theese
244. 
In TCA cycle, oxalosuccinate is converted to ?-ketoglutarate by the enzyme:

---

A. Fumarase
B. * Isocitrate dehydrogenase
C. Aconitase
D. Succinase
E. ?-ketoglutarate dehydrogenase
245. 
Most of the metabolic pathways are either anabolic or catabolic. Which of the 
following pathways is considered as “amphibolic” in nature?
A. Glycogenesis
B. Glycolytic pathway
C. Lipolysis
D. * TCA cycle
E. All of these
246. 
Out of 24 mols of ATP formed in TCA cycle, 2 molecules of ATP can be formed 
at “substrate level” by which of the following reaction ?
A. Citric acid>?Isocitric acid
B. Isocitrate>?Oxaloacetate
C. Succinic acid>?Fumarate
D. * Succinyl>?Succinic acid
E. Both A and D
247. 
Pyruvate dehydrogenase contains all except
A. * Biotin
B. NAD
C. FAD
D. CoA
E. Lipoic acid
248. 
The enzyme ?-ketoglutarate dehydrogenase in the citric acid cycle requires
A. * Lipoate
B. Folate
C. Pyridoxine
D. Inositol
E. NADP
249. 
The reaction catalysed by ?-ketoglutarate dehydrogenase in the citric acid cycle 
requires
A. * NAD
B. NADP
C. ADP
D. ATP
E. PLP
250. 
A distinct set of metabolic reactions is called a reaction ________________.
A. Network
B. Cycle
C. * Pathway
D. Mechanism
E. A and B
251. 
A specific inhibitor for succinate dehydrogenase is
A. Arsinite
B. * Melouate
C. Citrate
D. Cyanide
252. 
A specific inhibitor for succinate dehydrogenase is
A. Arsinite
B. * Malouate

---

C. Citrate
D. Cyanide
E. All of these
253. 
Acetyl CoA _________ pyruvate dehydrogenase complex and NADH 
__________ it.
A. activates; activates
B. activates; inhibits
C. * inhibits; inhibits
D. inhibits; activates
E. nome of the above
254. 
Acetyl CoA _________ pyruvate dehydrogenase complex and NADH 
__________ it.
A. activates; activates
B. activates; inhibits
C. * inhibits; inhibits
D. inhibits; activates
E. nome of the above
255. 
Aerobic oxidation of pyruvate to CO2 and H2O results in formation of molecules 
ATP:
A. 38 ATP
B. 12 ATP
C. 3 ATP
D. * 15 ATP
E. 2 ATP
256. 
After passing through the citric acid cycle, one mole of pyruvate will result in the 
formation of ______ moles of carbon dioxide and _________ mole(s) of ATP (or GTP).
A. 2; 2
B. 2; 1
C. 3; 2
D. * 3; 1
E. 1; 3
257. 
All enzymes and coenzymes of the pyruvate dehydrogenase complex are located 
in:
A. cytoplasm;
B. * matrix of mitochondria;
C. lysosomes;
D. partially in cytoplasm, partially in mitochondrial matrix.
E. all of the above
258. 
All of the following are allosteric enzymes except
A. Citrate synthetase
B. ?-Ketoglutarate dehdrogenase
C. * Succinate thiokinase
D. Succinate dehydrogenase
E. Both B and C
259. 
All of the following are intermediates of citric acid cycle except
A. Oxalosuccinate
B. Oxaloacetate
C. * Pyruvate
D. Fumarate
E. ?-Ketoglutarate
260. 
All of the following intermediates of citric acid cycle can be formed from amino 
acids except

---

A. ?-Ketoglutarate
B. Fumarate
C. * Malate
D. Oxaloacetate
E. B and C
261. 
Allosteric effector of enzymes of Krebs cycle which stimulate their oxidation is:
A. Succinate
B. * NAD+
C. NADH2
D. ATP
E. FADH2
262. 
Allosteric effector of enzymes of Krebs cycle which stimulate their oxidation is:
A. Succinate
B. * NAD+
C. NADH2
D. ATP
E. FADH2
263. 
An allosteric enzyme responsible for controlling the rate of T.C.A cycle is
A. Malate dehydrogenase
B. * Isocitrate dehydrogenase
C. Fumarase
D. Aconitase
E. All of the above
264. 
An allosteric enzyme responsible for controlling the rate of T.C.A cycle is
A. Malate dehydrogenase
B. * Isocitrate dehydrogenase
C. Fumarase
D. Aconitase
E. Both A and B
265. 
An amphibolic pathway among the following is
A. HMP shunt
B. Glycolysis
C. * Citirc acid cycle
D. Gluconeogenesis
E. All of these
266. 
An aneplerotic reaction which sustains the availability of oxaloacetate is the 
carboxylation of
A. Glutamate
B. * Pyruvate
C. Citrate
D. Succinate
E. Lactate
267. 
An enzyme of the citric acid cycle also found outside the mitochondria is
A. Isocitrate dehydrogenase
B. Citrate synthetase
C. * ?-Ketoglutarate dehydrogenase
D. Malate dehydrogenase
E. All of the above
268. 
Anabolic and catabolic reactions in eukaryotes can occur simultaneously in cells. 
This is possible because _______.
A. they all occur in the cytosol
B. the anabolic and catabolic pathways do not share any intermediate metabolites

---

C. * of the compartmentation of metabolites for the reactions of the opposing 
pathways
D. all catabolic reactions are exergonic and all anabolic reactions are endergonic
E. they all occur in the mitochondria
269. 
Carbons from acetyl CoA are transferred to the citric acid cycle. Which is the first 
round of the citric acid cycle that could possibly release a carbon atom originating from 
this acetyl CoA?
A. first round
B. * second round
C. third round
D. fourth round
E. fifth round
270. 
Catabolism is a form of metabolism in which molecules are converted into
A. * Simple end product, energy
B. Large start product
C. Peptides, protein
D. Food, storage
E. All of the above
271. 
Catabolism is characterized by _______________ of three major routs toward a 
final common pathway.
A. divergence;
B. * convergence;
C. splitting;
D. none of the above.
E. all of the above.
272. 
Central intermediate product of all of metabolism is:
A. * Acetyl-CoA
B. Succinyl-CoA
C. Oxaloacetate
D. Pyruvate
E. Citrate
273. 
Citrate has a positive allosteric effect on which one of the following enzymes?
A. Pyruvate kinase
B. * Acetyl CoA carboxylase
C. Phosphofructokinase
D. Fatty acid synthetase
E. Enolase
274. 
Citrate is converted to isocitrate by aconitase which contains
A. Ca++
B. * Fe++
C. Zn++
D. Mg++
E. Both A and B
275. 
Citrate is converted to isocitrate by aconitase which contains
A. Ca++
B. * Fe++
C. Zn++
D. Mg++
E. All of the above
276. 
Cofactors of dehydrogenases are all, except one:
A. NAD+
B. * c-AMP

---

C. NADP+
D. FMN
E. FAD
277. 
Consider the synthesis of a biopolymer in which the addition of successive 
monomers occurs by the same kind of reaction(s). The synthesis of the polymer is a 
________ pathway.
A. Linear
B. Cyclic
C. * Spiral
D. Branched
E. A and B
278. 
During succinyl CoA synthetesis generates
A. An energy deficient, unstable phosphoenzyme intermediate
B. An energy rich, unstable phosphoenzyme intermediate
C. * An energy rich, stable phopsphoenzyme intermediate
D. An energy deficient, stable phosphoenzyme intermediate
E. All of the above
279. 
Each of the following catalyzed reactions of the citric acid cycle appears to be 
metabolically irreversible except:
A. Citrate synthase
B. * Fumarase
C. Isocitrate dehydrogenase
D. Alpha ketoglutarate dehydrogenase complex
E. None of the above
280. 
Each of the following leads to a biosynthetic pathway except:
A. Alpha ketoglutarate
B. Succinyl CoA
C. Oxaloacetate
D. Citrate
E. * None of the above
281. 
Energy in biological systems is primarily
A. Electrical
B. * Chemical
C. Radiant
D. Mechanical
E. A and D
282. 
Energy is carried from catabolic to anabolic reactions in the form of
A. ADP
B. * High-energy ATP bonds
C. Coenzymes
D. Inorganic phosphate
E. Oxygen
283. 
Energy requiring metabolic pathways that yield complex molecules from simpler 
precursors are:
A. Amphibolic.
B. * Anabolic.
C. Autotrophic.
D. Catabolic.
E. Heterotrophic.
284. 
Fluoroacetate inhibits the reaction of citric acid cycle:
A. Isocitrate ?-Ketoglutarate
B. Fumarate -Malate

---

C. * Citrate -cis-aconitate
D. Succinate –fumarate
E. All of these
285. 
For one turn of Krebs cycle forms ATP (molecules):
A. 38 ATP
B. * 12 ATP
C. 15 ATP
D. 1 ATP
E. 15 ATP
286. 
Formation of succinyl-CoA from ?-Ketoglutarate is inhibited by
A. Fluoroacetate
B. * Arsenite
C. Fluoride
D. Iodoacetate
E. All of these
287. 
In citric acid cycle, NAD is reduced in
A. One reactions
B. Two reactions
C. * Three reactions
D. Four reactions
E. Five reactions
288. 
In eukaryotes the enzymes of the citric acid cycle are found in the _________.
A. cytosol
B. * mitochondria
C. nucleus
D. endoplasmic reticulum
E. both A and B
289. 
In eukaryotes the enzymes of the citric acid cycle are found in the _________.
A. cytosol
B. * mitochondria
C. nucleus
D. endoplasmic reticulum
E. all of these
290. 
Isocitrate dehydrogenase is allosterically inhibited by
A. Oxalosuccinate
B. ?-Ketoglutarate
C. * ATP
D. NADH
E. Both B and C
291. 
Malonate
A. Is a structural analogy of succinate
B. Binds to the substrate binding site of the succinate dehydrogenase complex but 
does not react
C. Undergoes an oxidation reaction
D. * Both a and b
E. All of the above
292. 
Malonate is an inhibitor of
A. Malate dehydrogenase
B. ?-ketoglutarate dehydrogenase
C. * Succinate dehydrogenase
D. Isocitrate dehydrogenase
E. Both C and D

---

293. 
Most of the metabolic pathways are either anabolic or catabolic. Which of the 
following pathways is considered as “amphibolic” in nature?
A. Glycogenesis
B. Glycolytic pathway
C. Lipolysis
D. * TCA cycle
294. 
NAD-dependent malate dehydrogenase
A. Catalyzes the oxidation of malate to regenerate oxaloacetate
B. Catalyzes the conversion of fumarase to malate
C. Catalyzes a reaction which results in the formation of an NADH molecule
D. All of the above
E. * a and c only
295. 
One molecule of glucose gives ______molecules of CO2 in TCA cycle.
A. * 6
B. 3
C. 1
D. 2
E. 12
296. 
Oxidative decarboxylation of pyruvate requires
A. NADP+
B. Cytichromes
C. pyridoxal phosphate
D. * COASH
E. All of the above
297. 
Oxidative decarboxylation of pyruvate requires
A. NADP+
B. Cytochromes
C. pyridoxal phosphate
D. * CoASH
E. Pyridoxine
298. 
Oxidative degradation of acetyl coenzyme A (CoA) in the citric acid cycle gives a 
net yield of which of the following chemicals?
A. Flavin adenine dinucleotide (FADF)
B. Nicotinamide adenine dinucleotide (NADN)
C. Adenosine triphosphate (ATP)
D. Guanosine diphosphate (GDP)
E. * Carbon dioxide (CO2)
299. 
Please match the following reaction Malate dehydrogenase to its respective 
energy yielding products shown in answers A through E.
A. * NADH
B. QH2
C. GTP or ATP
D. ADP
E. NAD
300. 
Please match the following reaction Succinate dehydrogenase complex to its 
respective energy yielding products shown in answers A through E.
A. NADH
B. * QH2
C. GTP or ATP
D. ADP
E. NAD

---

301. 
Please match the following reaction Succinyl CoA synthetase to its respective 
energy yielding products shown in answers A through E.
A. NADH
B. QH2
C. * GTP or ATP
D. ADP
E. NAD
302. 
Please match the following reaction Alpha ketoglutarate dehydrogenases complex 
to its respective energy yielding products shown in answers A through E.
A. * NADH
B. QH2
C. GTP or ATP
D. ADP
E. NAD
303. 
Please match the following reaction Isocitrate dehydrogenase to its respective 
energy yielding products shown in answers A through E.
A. * NADH
B. QH2
C. GTP or ATP
D. ADP
E. NAD
304. 
Product of a pathway controls the rate of its own synthesis by inhibiting an early 
step. Such way of enzyme regulation is called:
A. * feedback inhibition;
B. feed-forward activation;
C. autoregulation;
D. none of the above.
E. feedback activation
305. 
Product of a pathway controls the rate of its own synthesis by inhibiting an early 
step. Such way of enzyme regulation is called:
A. * feedback inhibition;
B. feed-forward activation;
C. autoregulation;
D. none of the above.
E. feedback activation
306. 
Prosthetic group of cytochrome is:
A. FAD
B. Ubiqinon
C. Biotin
D. * Iron porphyryn complex
E. Cooper contain porphyryn complex
307. 
Pyruvate can be form from all substrates, except one:
A. Lactate
B. Glycerol
C. Glucose
D. * Fatty acids
E. Glycogen
308. 
Pyruvate dehydrogenase complex and ?-ketoglutarate dehydrogenase complex 
require the following for their oxidative decarboxylation:
A. COASH and Lipoic acid
B. NAD+ and FAD
C. COASH and TPP

---

D. * COASH, TPP,NAD+,FAD, Lipoate
E. COASH, TPP, FAD, Lipoate
309. 
Substrates of the respiratory chain are all, except one:
A. Isocitrate
B. Malate
C. * Oxaloacetate
D. Succinate
E. E-кеtoglutarate
310. 
Substrates of the respiratory chain are all, except one:
A. Isocitrate
B. Malate
C. * Oxaloacetate
D. Succinate
E. E-кеtoglutarate
311. 
Substrates of the respiratory chain are all, except one:
A. Isocitrate
B. Malate
C. C-кеtoglutarate
D. Succinate
E. * Lactate
312. 
The activity of pyruvate carboxylase is dependent upon the positive allosteric 
effector
A. Succinate
B. AMP
C. Isocitrate
D. Citrate
E. * Acetyl CoA
313. 
The carrier of the citric acid cycle is
A. Succinate
B. Fumarate
C. Malate
D. * Oxaloacetate
E. All of these
314. 
The carrier of the citric acid cycle is
A. Succinate
B. Fumarate
C. Malate
D. * Oxaloacetate
E. All of the above
315. 
The citric acid cycle is inhibited by which of the following?
A. * Fluoroacetate
B. Fluorouracil
C. Aerobic conditions
D. Arsenic
E. Malic acid
316. 
The citric acid cycle is the _________________________________________.
A. * final common pathway for the catabolism of fuel molecules — carbohydrates, 
fatty acids and amino acids;
B. the anabolic pathway in which macromolecules are synthesized from monomers;
C. the biochemical pathway in which glucose is oxidized to acetyl CoA;
D. the biochemical pathway in which glucose is synthesized from noncarbohydrate 
components.

---

E. final common pathway for the catabolism of carbohydrates;
317. 
The citric acid cycle oxidizes pyruvate and some of the pathway intermediates are 
starting materials for many biosynthetic pathways. This means the citric acid cycle is a/an 
______________.
A. amplifying pathway
B. strictly catabolic pathway
C. anaerobic pathway
D. * amphibolic pathway
E. both A and D
318. 
The citric acid cycle oxidizes pyruvate and some of the pathway intermediates are 
starting materials for many biosynthetic pathways. This means the citric acid cycle is a/an 
______________.
A. amplifying pathway
B. strictly catabolic pathway
C. anaerobic pathway
D. * amphibolic pathway
319. 
The cycle of tricarboxilic acids begins with the reaction of substrates:
A. Pyruvate and acetyl CoA
B. Citric acid and acetyl CoA
C. * Oxaloacetate and acetyl CoA
D. Succinate and isocitrate
E. Isocitrate and oxaloacetate
320. 
The decarboxylation of pyruvate produces
A. NADH
B. Acetyl
C. CO2
D. ATP
E. * A, b, and c
321. 
The degradation of which class of biochemicals does not significantly contribute 
to the release of energy to cells?
A. * Nucleic acids
B. Proteins
C. Lipids
D. Carbohydrates
E. B and C
322. 
The degradative Processess are categorized under the heading of
A. Anabolism
B. * Catabolism
C. Metabolism
D. All of these
E. None of the above
323. 
The entry point into the citric acid cycle for isoleucine, valine, and the product of 
odd-chain fatty acids is
A. Fumarate
B. Pyruvate
C. * Oxaloacetate
D. Citrate
E. Succinyl CoA
324. 
The enzyme pyruvate translocase is located ______________.
A. in the cytosol
B. * in the inner mitochondrial membrane
C. in the mitochondrial matrix

---

D. in the endoplasmic reticulum
325. 
The enzymes of the citric acid cycle are located in
A. * Mitochondrial matrix
B. Extramitochondrial soluble fraction of the cell
C. Nucleus
D. Endoplasmic reticulum
E. Mitochondrial membrane
326. 
The enzymes of the Krebs cycle are located in the
A. * Cytoplasm
B. Inter-membrane space of mitochondria
C. Vesicles of the ER
D. Outer membrane of the mitochondria
E. Matrix of the mitochondria
327. 
The example of generation of a high energy phosphate at the substrate level in the 
citric acid cycle is the reaction:
A. Isocitrate >?-Ketoglutarate
B. Succinate > fumarate
C. Malate > oxaloacetate
D. * Succinyl CoA > Succinate
E. Both A and D
328. 
The flow of material through a reaction pathway usually depends on 
________________.
A. * Control at several steps in the pathway
B. Control of the first step of the pathway
C. Covalent modification of the enzyme that catalyzes the reaction
D. Feed-forward activation
E. Control of the second step of the pathway
329. 
The flow of material through a reaction pathway usually depends on 
________________.
A. * Control at several steps in the pathway
B. Control of the first step of the pathway
C. Covalent modification of the enzyme that catalyzes the reaction
D. Feed-forward activation
E. Control of the second step of the pathway
330. 
The following co-enzyme is needed for the oxidative decarboxylation of 
ketoacids:
A. NADP+
B. TPP
C. Folate coenzyme
D. Biotin coenzyme
E. None of these
331. 
The following coenzyme is needed for the oxidative decarboxylation of ketoacids:
A. NADP+
B. * TPP
C. Folate coenzyme
D. Biotin coenzyme
E. Both B and C
332. 
The function of protein kinase is:
A. synthesis of ATP from two ADP molecules;
B. catalysis of the oxidation-reduction reactions;
C. * phosphorylation of proteins (enzymes);
D. dephosphorylation of proteins (enzymes).

---

E. none of the above.
333. 
The initial step of the citric acid cycle is
A. Conversion of pyruvate to acetyl-CoA
B. * Condensation of acetyl-CoA with oxaloacetate
C. Conversion of citrate to isocitrate
D. Formation of ??-ketoglutarate catalysed by isocitrate dehydrogenase
E. Both A and B
334. 
The list of cofactors which are able in the process of fermentative reactions to 
carry electrons and protons is below resulted, except of one cofactor which carries 
chemical groups only. Choose it:
A. NAD
B. * Pyridoxal phosphate
C. FAD
D. Ubiqinon (coenzyme Q)
E. Hem coenzymes
335. 
The number of molecules of ATP produced by the total oxidation of acetyl CoA 
in TCA cycle is
A. 6
B. 8
C. 10
D. * 12
E. 15
336. 
The oxidation of acetyl CoA in citric acid cycle to CO2 and water is the 
_________ stage of catabolism and this is ___________ stage.
A. first, specific;
B. second, nonspecific;
C. third, specific;
D. * third, nonspecific.
E. second, specific.
337. 
The process by which a cell is built up from the simple nutrients obtained from its 
environment is called _____.
A. * Anabolism
B. Biosynthesis
C. Catabolism.
D. All of the above
E. More than one of the above, but not all
338. 
The reaction Pyruvate + CO2 + ATP + H2O ( Oxaloacetate + ADP + Pi is the 
example of ____________ reactions that ____________citric acid cycle intermediates.
A. anaplerotic; replenish;
B. catabolic; remove;
C. anabolic; remove;
D. * anaplerotic; remove.
E. all of the above
339. 
The reaction of Kreb’s cycle which does not require cofactor of vitamin B group 
is
A. * Citrate > isocitrate
B. ??-Ketoglutarate > succinate
C. Malate > oxaloacetate
D. Succinate > fumarate
E. Both A and D
340. 
The reaction succinyl CoA to succinate requires
A. CDP

---

B. * ADP
C. GDP
D. NADP+
E. TPP
341. 
The reaction succinyl COA to succinate requires
A. CDP
B. * ADP
C. GDP
D. NADP+
E. All of the above
342. 
The second stage of aerobic oxidation of glucose in a cell is oxidative 
decarboxilation of pyruvate. Name the main product of this proces.
A. * Acetyl CoA
B. Succinate
C. Pyruvate
D. Citrate
E. Oxaloacetate
343. 
The second stage of aerobic oxidation of glucose in a cell is oxidative 
decarboxilation of pyruvate. Name the main product of this proces.
A. Acetyl CoA
B. * Succinate
C. Pyruvate
D. Citrate
E. Oxaloacetate
344. 
The step at which acetyl CoA enters the citric acid cycle is classified as a 
___________ reaction.
A. * condensation
B. substrate-level phosphorylation
C. decarboxylation
D. dehydrogenation
E. oxidative phosphorylation
345. 
The step at which ATP releases in the citric acid cycle is classified as a 
___________ reaction.
A. condensation
B. * substrate-level phosphorylation
C. decarboxylation
D. dehydrogenation
E. oxidative phosphorylation
346. 
The step at which CO2 releases in the citric acid cycle is classified as a 
___________ reaction.
A. condensation
B. substrate-level phosphorylation
C. * decarboxylation
D. dehydrogenation
E. oxidative phosphorylation
347. 
The substance which may be considered to play a catalytic role in citric acid cycle 
is
A. * Oxaloacetate
B. Isocitrate
C. Malate
D. Fumarate
E. Succinyl CoA

---

348. 
The succinate dehydrogenase complex catalyzes
A. The formation of a single hydrogen bond in the oxidation of succinate to fumarate
B. * The formation of a double bond in the oxidation of succinate to fumarate
C. Both a and b
D. The formation of a macroergic bond
E. None of the above
349. 
The TCA cycle:
A. Is found in the cytosol
B. * Is controlled by calcium ion, the ADP/ATP ratio, and the NADH concentration
C. Is also called the Cori cycle
D. Consumes most of the CO2 produced by ribosomes
E. Produces most of the water made in humans
350. 
The temperature of human body supported due to all of processes, except one:
A. Katabolism of proteinsns, lipids, carbohydrates (specific stage)
B. Glycolysis
C. Katabolism (general stage)
D. TCA and oxidative phosphorylating
E. * Gluconeogenesis
351. 
The transfer of free energy from catabolic pathways to anabolic pathways is best 
called
A. Feedback regulation.
B. Bioenergetics.
C. Cooperativity.
D. * Energy coupling.
E. Entropy.
352. 
There are ____ enzymes in the pyruvate dehydrogenase complex and ____ 
coenzymes: _______________________________________________.
A. 5; 5: TPP, lipoamide, HS-CoA, FAD+, NAD+
B. * 3; 5: TPP, lipoamide, HS-CoA, FAD+, NAD+
C. 3; 5: PLP, lipoamide, HS-CoA, FAD+, NADP+
D. 4; 5: PLP, lipoamide, HS-CoA, FAD+, NADP+
E. 5; 5: PLP, lipoamide, HS-CoA, FAD+, NADP+
353. 
There are 4 main functions of Krebs cycle, except:
A. Oxidation of acetic acid into СО2 і Н2О
B. Donator of hydrogen atoms for respiratory chain
C. * Oxidation of lactate into pyruvate
D. Formation of ATP
E. Supplying substrates for heme synthesis
354. 
There are 4 main functions of Krebs cycle, except:
A. Oxidation of acetic acid into СО2 і Н2О
B. * Donator of hydrogen atoms for respiratory chain
C. Oxidation of lactate into pyruvate
D. Formation of ATP
E. Supplying substrates for heme synthesis
355. 
There are such three enzymes in pyruvate dehydrogenase complex:
A. Pyruvate carboxylase, lactate dehydrogenase, citrate synthase
B. * Pyruvate dehydrogenase, dihydrolipoyl acetyl transferase, dihydrolipoyl 
dehydrogenase.
C. Ketoglutarate dehydrogenase, acetyltransferase, aconitase
D. NАDН2- dehydrogenase
E. Succinate dehydrogenase, aldehyde dehydrogenase.
356. 
Tricarboxylic acid cycle to be continuous requires the regeneration of

---

A. Pyruvic acid
B. * oxaloacetic acid
C. ?-oxoglutaric acid
D. Malic acid
E. Fatty acids
357. 
Tricarboxylic acid cycle to be continuous requires the regeneration of
A. Pyruvic acid
B. * oxaloacetic acid
C. ?-oxoglutaric acid
D. Malic acid
E. Fumaric acid
358. 
Unlike NADH and NADPH, FAD and FADH
A. Donate one electron at a time
B. Donate one or two electrons at a time
C. Do not become positively charged
D. a and c
E. * b and c
359. 
Where in a cell the tricarboxylic acid cycle takes place?
A. Within the inner compartment of the mitochondrion.
B. * In cytoplasm.
C. In nucleus.
D. In ribosomes.
E. All of these
360. 
Which 5-carbon intermediate of the citric acid cycle is converted to a 4-carbon 
molecule with the release of carbon dioxide?
A. fumarase
B. * а-ketoglutarate
C. succinate
D. isocitrate
E. citrate
361. 
Which carbon atom(s) of pyruvate is(are) first converted to carbon dioxide by 
pyruvate dehydrogenase complex?
A. * the carboxylate carbon (#1)
B. the carbonyl carbon (#2)
C. the methyl carbon (#3)
D. both carbons #1 and #3 in equal amounts
E. all of the above
362. 
Which cofactor is not used by the pyruvate dehydrogenase complex?
A. lipoamide
B. thiamine pyrophosphate
C. FAD
D. * QH2
E. HS-CoA
363. 
Which cofactor is not used by the pyruvate dehydrogenase complex?
A. lipoamide
B. thiamine pyrophosphate
C. FAD
D. * NAD
E. PLP
364. 
Which enzyme catalyzes a metabolically irreversible reaction?
A. aconitase
B. * isocitrate dehydrogenase

---

C. fumarase
D. malate dehydrogenase
E. All of the above
365. 
Which enzyme catalyzes a reaction that releases carbon dioxide?
A. a-ketoglutarate dehydrogenase complex
B. pyruvate dehydrogenase
C. * malate dehydrogenase
D. aconitase
E. both A and B
366. 
Which enzyme catalyzes the citrate synthesis?
A. aldolase
B. * citrate synthase
C. citrate isomerase
D. aconitase
E. citrate dehydrogenase
367. 
Which enzyme catalyzes the conversion of citrate to isocitrate?
A. aldolase
B. citrate synthase
C. citrate isomerase
D. * aconitase
E. epimerase
368. 
Which enzyme does not catalyze a reaction that releases carbon dioxide?
A. A-ketoglutarate dehydrogenase complex
B. pyruvate dehydrogenase
C. * malate dehydrogenase
D. isocitrate dehydrogenases
E. both A and C
369. 
Which enzyme does not catalyze a reaction that releases carbon dioxide?
A. a-ketoglutarate dehydrogenase complex
B. pyruvate dehydrogenase
C. * malate dehydrogenase
D. isocitrate dehydrogenases
E. All of these
370. 
Which enzyme is the same in both pyruvate dehydrogenase complex and a-
ketoglutarate complex?
A. * dihydrolipoamide dehydrogenase
B. aconitase
C. pyruvate decarboxylase
D. The two complexes have no components that are similar
E. Both A and B
371. 
Which enzyme is the same in both pyruvate dehydrogenase complex and а-
ketoglutarate complex?
A. * dihydrolipoamide dehydrogenase
B. aconitase
C. pyruvate decarboxylase
D. The two complexes have no components that are similar.
E. Dihydrolipoamide kinase
372. 
Which intermediate of the citric acid cycle has a plane of symmetry?
A. * succinate
B. citrate
C. succinyl CoA
D. а-ketoglutarate

---

E. all of these
373. 
Which is not a component of the Alfa ketoglutarate dehydrogenase complex?
A. dihydrolipoamide dehydrogenase
B. Alfa ketoglutarate dehydrogenase
C. * pyruvate dehydrogenase
D. dihydrolipoamide acetyltransferase
E. All of the above
374. 
Which is not a component of the pyruvate dehydrogenase complex?
A. dihydrolipoamide dehydrogenase
B. * isocitrate dehydrogenase
C. pyruvate dehydrogenase
D. dihydrolipoamide acetyltransferase
E. both B and D
375. 
Which is not a component of the pyruvate dehydrogenase complex?
A. dihydrolipoamide dehydrogenase
B. * Alfa ketoglutarate dehydrogenase
C. pyruvate dehydrogenase
D. dihydrolipoamide acetyltransferase
E. All of the above
376. 
Which is not produced by the citric acid cycle?
A. NADH
B. * FMN
C. CO2
D. FADH2
E. none of the above
377. 
Which is usually the slowest way to regulate a reaction in a metabolic pathway?
A. Allosteric modulation
B. Covalent modification
C. * Changing the enzyme concentration
D. All of the above are usually equally as fast
E. Competitive inhibitor
378. 
Which is usually the slowest way to regulate a reaction in a metabolic pathway?
A. Allosteric modulation
B. Covalent modification
C. * Changing the enzyme concentration
D. All of the above are usually equally as fast
E. Competitive inhibitor
379. 
Which of the following allosterically activates mammalian isocitrate 
dehydrogenase?
A. ADP
B. NADH
C. Calcium
D. All of the above
E. * a and c only
380. 
Which of the following are components of the succinate dehydrogenase complex?
A. FAD prosthetic group
B. Iron-sulfur clusters
C. Malonate
D. All of the above
E. * a and b only
381. 
Which of the following describe(s) some aspect of metabolism?
A. Breakdown of macromolecules

---

B. Synthesis of macromolecules
C. Control of enzyme activity
D. * A and B only
E. A, B, and C
382. 
Which of the following is (are) true for anabolic pathways?
A. They do not depend on enzymes.
B. They are highly regulated sequences of chemical reactions.
C. * They consume energy to build up polymers from monomers.
D. They release energy as they degrade polymers to monomers.
E. Both B and C
383. 
Which of the following is (are) true for anabolic pathways?
A. Catabolism involves the breakdown of energy-poor substrates into monomers. 
Anabolism creates energy rich substrates from these monomers. Metabolism is 
the sum of both of these processes
B. Catabolism is the breakdown of nutrients, anabolism is the generation of ATP. 
Metabolism is the sum of both of these processes.
C. * Catabolism uses energy to breakdown nutrients into intermediates for 
biosynthesis. Anabolism uses the intermediates for biosynthesis. Metabolism is 
the sum of both of these processes.
D. Catabolism involves the multi-step breakdown of energy-rich nutrients into 
smaller compounds; during this process energy is released. Anabolism uses the 
energy released and the smaller compounds as intermediates for biosynthesis. 
Metabolism is the sum of both of these processes
E. Anabolism involves the multi-step breakdown of energy-rich nutrients into 
smaller compounds; during this process energy is released. Catabolism uses the 
energy released and the smaller compounds as intermediates for biosynthesis. 
Metabolism is the sum of both of these processes
F. They do not depend on enzymes.
G. They are highly regulated sequences of chemical reactions.
H. They consume energy to build up polymers from monomers.
I. They release energy as they degrade polymers to monomers.
J. Both B and C
384. 
Which of the following is not a fate of a citric acid cycle intermediate?
A. Alpha ketoglutarate reversibly converting to glutamate
B. The biosynthesis of porphyrins from succinyl CoA's interaction with glycine
C. Oxabacetate as a carbohydrate precursor
D. * Acetyl CoA as fatty acids precursor
E. None of the above
385. 
Which of the following is/are true statements about the succinate dehydrogenase 
reactions?
A. * It is stereospecific
B. Only the cis-isomer of the product is formed
C. It is not stereospecific
D. Both b and c
E. Both a and b
386. 
Which of the following metabolite integrates glucose and fatty acid metabolism?
A. * Acetyl CoA
B. Pyruvate
C. Citrate
D. Lactate
E. Fumarate
387. 
Which of the following statements is false?

---

A. Phosphofructokinase is the rate limiting enzyme in glycolysis
B. Phosphorylase activity is higher in Type II fibres than in Type I fibres
C. Endurance training increases the amount of TCA cycle enzymes in muscle
D. * Oxygen is consumed in the TCA cycle
E. The heart can oxidise lactate
388. 
Which of the following statements is TRUE concerning catabolic pathways?
A. They build up complex molecules such as protein from simpler compounds.
B. They combine molecules into more complex and energy-rich molecules.
C. They are spontaneous and do not need enzyme catalysis.
D. They involve endergonic reactions that break complex molecules into simpler 
ones.
E. * They are usually coupled with anabolic pathways to which they supply energy 
in the form of ATP.
389. 
Which of the following statements regarding T.C.A cycle is true?
A. It is an anaerobic process
B. It occurs in cytosol
C. It contains no intermediates for Gluconeogenesis
D. * It is amphibolic in nature
E. A and B
390. 
Which of the following statements regarding T.C.A cycle is true?
A. It is an anaerobic process
B. It occurs in cytosol
C. It contains no intermediates for Gluconeogenesis
D. * It is amphibolic in nature
E. Both A and D
391. 
Which of the following statements regarding the four "dehydrogenases" of the 
TCA cycle is INCORRECT?
A. These are enzymes which remove electrons in the form of hydrogen from various 
structures and transfer them to others
B. At least one catalyzes the "rate-limiting steps" of the TCA cycle
C. * GTP is generated from one of them via substrate level phosphorylation
D. NAD+ and FAD are the electron-accepting coenzymes for these enzymes
E. At least one catalyzes a reversible reactions
392. 
Which statement does not explain why many biochemical processes are carried 
out via multi-step pathways rather than by single-step reactions (or only a few steps)?
A. Multi-step pathways allow for more control points to regulate biochemical 
processes.
B. * The end products of most pathways can usually be produced only by the 
pathway reactions that nature has evolved.
C. Sharing of intermediates between pathways is facilitated this way.
D. There is greater control over the amounts of energy that are consumed or released 
at any one time.
E. None of the above
393. 
Which statement is false about most metabolic pathways?
A. * Most pathways are reversible under physiological conditions.
B. Pathways serve to increase the efficiency of energy transfers.
C. The rates of pathway reactions vary to respond to changing conditions.
D. The enzymes that catalyze reactions in metabolic pathways generally catalyze 
only a single step.
E. Most pathways are irreversible under physiological conditions.
394. 
Which statement is false about most metabolic pathways?
A. * Most pathways are reversible under physiological conditions.

---

B. Pathways serve to increase the efficiency of energy transfers.
C. The rates of pathway reactions vary to respond to changing conditions.
D. The enzymes that catalyze reactions in metabolic pathways generally catalyze 
only a single step.
E. Most pathways are irreversible under physiological conditions.
395. 
Which statement is not true about catabolic pathways?
A. They have a net release of energy.
B. * They have a net consumption of ATP.
C. They liberate smaller molecules from larger ones.
D. They include the citric acid cycle.
E. None of the above.
396. 
Which statement is not true about catabolic pathways?
A. They have a net release of energy.
B. They have a net consumption of ATP.
C. They liberate smaller molecules from larger ones.
D. They include the citric acid cycl
E. A and C only
397. 
Which step in the citric acid cycle is a rearrangement reaction?
A. succinyl CoA to succinate
B. fumarate to L-malate
C. * citrate to isocitrate
D. glucose 1,6-bisphosphate to fructose 1,6-bisphosphate
E. none of the above
398. 
Which term most precisely describes the cellular process of breaking down large 
molecules into smaller ones?
A. Dehydration
B. Catalysis
C. Anabolism
D. * Catabolism
E. Metabolism
399. 
Which term most precisely describes the general process of breaking down large 
molecules into smaller ones?
A. Anabolism
B. Catalysis
C. * Catabolism
D. Dehydration
E. Metabolism
400. 
Why is ATP an important molecule in metabolism?
A. * It provides energy coupling between exergonic and endergonic reactions.
B. Its hydrolysis provides an input of free energy for exergonic reactions.
C. Its terminal phosphate group contains a strong covalent bond that when 
hydrolyzed releases free energy.
D. A and B only
E. A, B and C
401. 
Within the inner matrix of the mitochondrion are:
A. * The enzymes of the tricarboxylic acid cycle (Krebs’ cycle)
B. The components of the electron transport chain
C. Glycogen molecules
D. The enzymes of gluconeogenesis
E. The enzymes creatine kinase and carnitine acyl transferase 1
402. 
Within the inner matrix of the mitochondrion are:
A. * The enzymes of the tricarboxylic acid cycle (Krebs’ cycle)

---

B. The components of the electron transport chain
C. Glycogen molecules
D. The enzymes of gluconeogenesis
E. The enzymes creatine kinase and carnitine acyl transferase 1
403. 
The notion that ATP is generated by a proton gradient existing across a membrane 
is called
A. Proton motion
B. Lactate reduction.
C. Cytochromic flow.
D. * Chemiosmotic theory.
E. Pyruvat decarboxilation
404. 
A biological redox potential of reaction always involves:
A. * А loss of electrons
B. A gain of electrons
C. A reducing agent
D. An oxidizing agent
E. All of the above
405. 
A reaction that is facilitated by FADH2 is most likely a(n)
A. Oxidation
B. * Reduction
C. Hydrolysis
D. Isomerization
E. None of the above.
406. 
All of the following molecules are directly involved in the electron transport chain 
except
A. Coenzyme Q
B. O2
C. * Pyruvate
D. FADH2
E. Cytochrome c
407. 
All of the following situations are consistent with active transport EXCEPT
A. The conversion of ATP to ADP accompanies the movement of molecules.
B. The rate of oxygen consumption by the cell increases when molecules move
C. Molecules move in or out of a cell against the osmotic gradient
D. Cells accumulate diffusible molecules in greater quantity than was found outside 
the cell.
E. * The rate of movement of molecules across the cell membrane increases i an 
anaerobic environment.
408. 
An increase in the level of cellular ATP is likely to occur under which of the 
following conditions?
A. * Increased activity of catabolic pathways
B. Decreased activity of anabolic pathways
C. Allosteric inhibition of anabolic pathways
D. A and B only
E. A, B, and C
409. 
Antibiotic antimycin blocks electron transport in the span from:
A. NADH to Fe-S proteins
B. Cytochrom c to aa3
C. * NADH to ubiquinone
D. Cytochrome b to c
E. NADH to cytochrome b
410. 
Compare the pH of the mitochondrial matrix and inner membrane space.

---

A. The pH is lower in the matrix.
B. The pH in both regions is the same.
C. * The pH is lower in the inner membrane space.
D. The comparison of pH varies from moment to moment depending on energy 
needs of the cell.
E. A and B only
411. 
Cyanide is a poison that blocks the passage of electons along the electron 
transport chain. Which of the following is a metabolic effect of this poison?
A. The pH of the intermembrane space becomes much lower than normal
B. Electrons are passed directly to oxygen, causing cells to explode
C. Alcohol would build up in the cells
D. NADH supplies would be exhasted, and ATP synthesis would cease.
E. * No proton gradient would be produced, and ATP synthesis would cease.
412. 
Cyanide, oligomycin, and 2,4-dinitrophenol (DNP) are inhibitors of mitochondrial 
aerobic phosphorylation. Which of the following statements correctly describes the mode 
of action of the three inhibitors?
A. Cyanide and 2,4-dinitrophenol inhibit the respiratory chain, and oligomycin 
inhibits the synthesis of ATP.
B. * Cyanide inhibits the respiratory chain, whereas oligomycin and 2,4-
dinitrophenol inhibit the synthesis of ATP.
C. Cyanide, oligomycin, and 2,4-dinitrophenol compete with O2 for cytochrome 
oxidase (Complex IV).
D. Oligomycin and cyanide inhibit synthesis of ATP; 2,4-dinitrophenol inhibits the 
respiratory chain.
E. Oligomycin inhibits the respiratory chain, whereas cyanide and 2,4-dinitrophenol 
prevent the synthesis of ATP.
413. 
Cytochromes a and a3 together are called :
A. Succinare dehydrogenase
B. Transaminase
C. Acorbatoxidase
D. * Cytochrome c oxidase
E. None of the above
414. 
During aerobic respiration, electrons travel downhill from
A. Food-->Krebs Cycle-->ATP--> NAD+
B. * Food-->NADH-->electron transport chain-->oxygen
C. Glucose-->ATP-->oxygen
D. Glucose-->ATP-->electron transport chain-->NADH
E. Food-->glycolysis-->Krebs Cycle-->NADH-->ATP
415. 
During ATP synthesis, the three identical b subunits of the F1 complex
A. * Have similar affinities for ADP and ATP
B. Have different affinities for ADP but not for ATP
C. Have different affinities for ATP but not for ADP
D. Have different affinities for ATP and for ADP
E. Do not bind ADP until a proton dissociates
416. 
During cell respiration, most ATP is formed as a direct result of the net movement 
of
A. Sodium ions diffusion across a membrane
B. Electrons flowing against a gradient
C. Electrons flowing througth a channel
D. * Protons flowing througth a channel
E. Protons flowing against a gradient
417. 
During respiration, the substrate is

---

A. Reduced
B. Hydrogenated
C. Carbonated
D. * Oxidised
E. A and D
418. 
FMN - prosthetic group of:
A. Lactatdehydrogenase
B. * NADH- dehydrogenase
C. Alcoholdehydrogenase
D. Creatincinase
E. Aminotranspherase
419. 
For very high force contractions lasting 1-2 seconds, the initial energy source is 
from:
A. Glycolysis
B. Creatine phosphorylation
C. Phosphocreatine stores
D. * ATP stores
E. None of the above
420. 
How many ways of ATP formation are in the organism?
A. 1
B. * 2
C. 10
D. 3
E. 5
421. 
In a fermentation metabolism, the organism produces ATP by
A. More than one of the above
B. * Generation of a proton motive force by transfer of electrons to oxygen.
C. Oxidizing NADH to form the proton motive force.
D. Substrate level phosphorylation.
E. None of the above
422. 
In general, the higher the intensity of exercise, the greater the proportional 
contribution of:
A. Aerobic energy production
B. * Anaerobic energy production
C. The TCA cycle (Krebs’ cycle) to the production of ATP
D. The electron transfer chain to the production of ATP
E. Fat oxidation
423. 
In the chemiosmotic mechanism:
A. * ATP produciton is linked to the proton gradient established by the electron 
transport chain.
B. The difference in pH between the intermembrane space and the cytosol drives the 
formation of ATP.
C. The flow of H+ through ATP synthases from the matrix to the intermembrane 
space drives the phosphorylation of ADP.
D. The energy released by the reduction and subsequent oxidation of components of 
the electron transport chain is transferred as a phosphate to ADP.
E. The produciton of water in the matrix by the reduciton of oxygen leads to a net 
flow of water out of a mitochondrion.
424. 
Living organisms increase in complexity as they grow, resulting in a decrease in 
the entropy of an organism. How does this relate to the second law of thermodynamics?
A. * Life obeys the second law of thermodynamics because the decrease in entropy 
as the organism grows is balanced by an increase in the entropy of the universe.

---

B. As a consequence of growing, organisms create more disorder in their 
environment than the decrease in entropy associated with their growth
C. Living organisms are able to transform energy into entropy.
D. Living organisms do not obey the second law of thermodynamics, which states 
that entropy must increase with time.
E. Living organisms do not follow the laws of thermodynamics.
425. 
NADI-reagent include:
A. H2SO4 and ?-naphtol
B. * Para-phenilendiamine and B-naphtol
C. 2,4 - dinitrophenol and C-naphtol
D. Starch and para-phenilendiamine
E. None of the above
426. 
Pyridine-linked dehydrogenases require as coenzymes:
A. FAD, FMN
B. * NAD, NADP
C. TPP, TDP
D. Coenzym A
E. THFA
427. 
Reactants capable of interacting to form products in a chemical reaction must first 
overcome a thermodynamic barrier known as the reaction's
A. Entropy.
B. Activation energy.
C. Endothermic level.
D. * Free-energy content.
E. Heat content.
428. 
Several inhibitors block electron transport in the span between NADH and 
ubiquinone, except:
A. Rotenone
B. Amytal
C. Piericidin
D. * Valinomicin
E. None of the above
429. 
Substrates for respiratory chain are formed in:
A. Cytoplasm
B. Glycolysis
C. * Krebs cycle
D. Endoplasmic reticulum
E. Gluconeogenesis
430. 
The _______ is a unit of chemical energy
A. Grams
B. Volts
C. * Joules/mol
D. Kilocalorie
E. More than one of the above
431. 
The 1-st reaction of substrate-level phosphorylation takes place in the 
mitochondria matrix and is located in:
A. * Respiratory chain
B. Decarboxilation of pyruvat
C. Gluconeogenesis
D. Krebs cycle
E. Oxidation of fatty acids

---

432. 
The amount of energy required to bring all molecules to a reactive state prior to a 
chemical reaction is called the reaction's _____________.
A. Van der Waal's energy
B. Go'
C. Free energy of formation
D. * Activation energy
E. More than one of the above is correct
433. 
The antibiotic oligomycin serves as:
A. Activator of respiratiry chain
B. The ingibitor of Krebs cycle
C. * The inhibitor of oxidative phosphorylation
D. The ingibitor of substrate-level phosphorylation
E. None of the above
434. 
The ATP produced during fermentation is generated by which of the following?
A. The electron transport chain
B. * Substrate-level phosphorilation
C. Krebs cycle
D. Chemiosmosis
E. Citric acid cycle
435. 
The cytochromes are localized in the:
A. Cytosol
B. Nucleus
C. * Inner mitochondrial membrane
D. Ribosoms
E. Matrix of mitochondria
436. 
The direct energy source that drives ATP synthesis during respiratory oxidative 
phosphorylation is
A. Oxidation of glucose to CO2 and water
B. The thermodynamically favorable flow of electrons from NADH to the 
mitochondrial electron transport carriers
C. The final transfer of electrons to oxygen
D. * The difference in H+ concentration on opposite sides of the inner mitochondrial 
membrane
E. Thermodynamically favorable transfer of phosphate molecules (from glycolysis 
and Krebs cycle intermediates) to ADP
437. 
The electrons released by FADH2 during its oxidation to FAD by the electron 
transport system finally end up as part of this molecule:
A. Glucose
B. * Water
C. Carbon dioxide
D. ATP
E. CO
438. 
The immediate energy source that drives ATP synthesis by ATP synthase during 
oxidative phosphorylation is :
A. The flow of electrons down the electron transport chain.
B. * The H+ concentration gradient across the inner mitochondrial membrane.
C. The oxidation of glucose and other organic compounds.
D. The transfer of phosphate to ADP.
E. The affinity of oxygen for electrons.
439. 
the inner mitochondrial membrane.
A. The concentration of reduced coenzymes outside the mitochondrial
B. The energy difference between reduced carbon atoms and oxidized

---

C. * The concentration difference of hydrogen ions between the two sides of
D. The hydrolylsis of ATP to form ADP and Pi.
E. More than one of the above.
440. 
The iron-sulfur proteins appear to function as electron carriers by undergoing 
reversible :
A. Cu (I) to Cu (II) transitions
B. Na (I) to Na (II) transitions
C. Mg (I) to Mg (II) transitions
D. * Fe(II)-Fe(III) transitions.
E. None of the above
441. 
The major reason that glycolysis is not as energy productive as respiration is that:
A. * NAD+ is regenerated by alcohol or lactate production, without the high-energy 
electrons passing through the electron transport chain.
B. It is the pathway common to fermentation and respiration.
C. It does not take place in a specialized membrane bound organelle.
D. Pyruvate still contains much of the energy from glucose.
E. Substrate level phosphorylation is not as energy efficient as oxidative 
phosphorylation.
442. 
The metabolic function of fermentation is to:
A. Oxidize NADH to NAD+ so that glycolysis can continue in the absense of 
oxygen.
B. Reduce NADH so that more ATP can be produced by the electron transport chain
C. Produce lactate during aerobic exercises
D. Oxidize pyruvate, thus releasing more energy.
E. * Make beer
443. 
The metal ion that acts as an electron carrier in the cytochromes in the electron 
transport chain is
A. Magnesium
B. Chromium
C. * Iron
D. Cobalt
E. Hydrogen
444. 
The most common substrate of respiration is _________.
A. Amino acids
B. Fats
C. * Glucose
D. Sucrose
E. Vitamins
445. 
The prototype of ionophores is the antibiotic:
A. Oligomicin
B. * Valinomycin
C. Antimicin
D. Piericidin
E. None of the above
446. 
The terminal cytochrome of mitochondrial respiration include tightly bound:
A. Na
B. P
C. * Cu
D. CI
E. Mg
447. 
There are four types of electron-transferring enzymes, except:
A. Pyridine-linked dehydrogenases

---

B. Flavin-linked dehydrogenases
C. Iron-sulfur proteins
D. * Retinol-isomerase
E. Cytochromes
448. 
Ways of ATP formation in the organism:
A. Hydrolysis of simple proteins and separation of amino acid
B. Salting-out and denaturation of proteins
C. * Oxidative phosphorylation and substrate-level phosphorylation.
D. Decarboxilation of pyruvat and gluconeogenesis
E. All of above
449. 
What is the change in free energy of a system at chemical equilibrium?
A. * No net change
B. Slightly increasing
C. Slightly decreasing
D. Greatly increasing
E. Greatly decreasing
450. 
Where is ATP formed during oxidative phosphorylation ?
A. In the mitochondria
B. In the cytoplasm
C. In the respiratory chain
D. On the cytochromes
E. * On the ATP-synthase, which is located in the mitochondrial matrix and 
penetrate inner membrane
451. 
Which of the following class of vitamins are found in NAD, FAD, and FMN?
A. Water soluble
B. Coenzymes
C. * B vitamins
D. Antioxidants
E. More than one of the above.
452. 
Which of the following coenzymes would have to be continually present in the 
cell in order for the oxidative reactions of glycolysis to continue?
A. FADH2
B. * NADH
C. ATP
D. NAD+
E. All of the above
453. 
Which of the following describe(s) some aspect of metabolism?
A. Breakdown of macromolecules
B. Synthesis of macromolecules
C. Control of enzyme activity
D. * A and B only
E. A, B, and C
454. 
Which of the following forms of energy is least available to accomplish cellular 
work?
A. Electrical energy
B. * Mechanical energy
C. Light energy
D. Thermal energy (heat)
E. Potential energy
455. 
Which of the following is (are) true for anabolic pathways?
A. They do not depend on enzymes.
B. They are highly regulated sequences of chemical reactions.

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C. * They consume energy to build up polymers from monomers.
D. They release energy as they degrade polymers to monomers.
E. Both B and C
456. 
Which of the following is not a significant biological oxidizing agent?
A. Fe3+
B. NAD+
C. FAD
D. Ubiquinone (a.k.a. CoQ)
E. * O2
457. 
Which of the following produces ATP, reduced coenzymes as high energy 
molecules and CO2 as its major chemical waste product.
A. Electron transport
B. Glycolysis
C. beta – oxidation or fatty acids
D. * Citric acid cycle
E. Oxidative phosphorylation
458. 
Which of the following reaction is incorrectly paired with its location?
A. * ATP synthesis>inner membrane of the mitochondrion, matrix, and cytosol.
B. Fermentation>cell cytosol
C. Glycolysis>cell cytosol
D. Substrate-level phosphorylation>cytosol and matrix
E. Citric acid cycle>cristae of mitochondrion
459. 
Which of the following statements is true about the role of O2 in electron 
transport?
A. * As the final electron acceptor, O2 gets reduced and becomes a part of a water 
molecule.
B. As the final electron donator, O2 gets oxidized and becomes a part of an ATP 
molecule.
C. As the final electron acceptor, O2 gets reduced and becomes a part of an ATP 
molecule.
D. As the final electron donator , O2 gets oxidized and becomes a part of a NADH 
molecule.
E. None of the above.
460. 
Which process of cell respiration is most closely associated with intracellular 
membranes?
A. Fermentation
B. The Krebs cycle
C. Glycolysis
D. Substrate-level phosphorilation
E. * Oxidative phosphorilation
461. 
Which term most precisely describes the cellular process of breaking down large 
molecules into smaller ones?
A. Dehydration
B. Catalysis
C. Anabolism
D. * Catabolism
E. Metabolism
462. 
Why is ATP an important molecule in metabolism?
A. * It provides energy coupling between exergonic and endergonic reactions.
B. Its hydrolysis provides an input of free energy for exergonic reactions.
C. Its terminal phosphate group contains a strong covalent bond that when 
hydrolyzed releases free energy.

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D. A and B only
E. A, B and C

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