MCQ module 1

Dear students, as I told you I give you all questions from yours first module.
Enjoy :)

1. A deficiency of vitamin B12 causes:
a. Cheilosis
b. Beriberi
c. Pernicious anemia
d. Scurvy
e. Rickets
2. The vitamin required for the formation of hydroxyproline (in collagen) is
(A) Vitamin C
(B) Vitamin A
(C) Vitamin D
(D) Vitamin E
3. In new born infants phototherapy may cause hyperbilirubinemia with deficiency of
(A) Thiamin
(B) Riboflavin
(C) Ascorbic acid
 (D) Pantothenic acid
4. The Vitamin which does not contain a ring in the structure is
(A) Pantothenic acid
(B) Vitamin D
(C) Riboflavin
 (D) Thiamin
5. Consumption of raw eggs can cause deficiency of
(A) Biotin
(B) Pantothenic acid
(C) Riboflavin
 (D) Thiamin
6. Folate deficiency causes
(A) Microcytic anemia
(B) Hemolytic anemia
(C) Iron deficiency anemia
(D) Megaloblastic anemia
7. FAD is a coenzyme for
(A) Succinate dehydrogenase
(B) Glycerol-3-phosphate dehydrogenase
(C) Sphingosine reductase
(D) All of these
8. Daily requirement of niacin is
(A) 5mg
(B) 10mg
(C) 20mg
(D) 30mg
9. Biotin is required as a coenzyme by
(A) Anaerobic dehydrogenases
(B) Decarboxylases
(C) Aerobic dehydrogenases
(D) Carboxylases
10. Deficiency of vitamin C causes
(A) Beriberi
(B) Pellagra
(C) Pernicious anemia
(D) Scurvy
11. An early effect of vitamin A deficiency is
(A) Xerophthalmia
(B) Keratomalacia
(C) Prolonged dark adaptation time
(D) Follicular hyperkeratosis
12. Cholesterol is a precursor in the biogenesis of
(A) Vitamin A
 (B) Vitamin D
(C) Vitamin E
 (D) None of these
13. Sulpha drugs are antimetabolites of
(A) PABA
(B) Pyridoxine
(C) Vitamin B2
(D) Pantothenic acid
14. Transketolase activity is affected in
(A)  Biotin deficiency

(B)  Pyridoxine deficiency

(C)  PABA deficiency

(D)  Thiamine deficiency

15. Avitaminosis of what vitamin can significantly decrease the aminotransferase activity in blood serum?

(A) В9, folic acid

(B) В1 thiamin
(C) В2 riboflavin
(D) В5 nicotinic acid
(E) b6 pyridoxine
16. Which ONE of the following amino acid substitutions most likely causes a change in a protein's tertiary structure?
A. Isoleucine to arginine
B. Arginine to lysine
C. Valine to leucine
D. Threonine to serine
E. Asparagine to glutamine
17. Glycogen phosphorylase, which mobilizes glycogen for energy, requires which of the following as a cofactor?
a) Pyridoxal phosphate
b) Tetrahydrofolate
c) Adenosyl Cobalamine
d) Coenzyme A       
18. A 54-year –old male was rushed to emergency when he collapsed in the middle of a business meeting. Examination revealed excessive sweating and high blood pressure. ECG chest was conclusive of Acute Myocardial infarction. Which biochemical investigation out of the following would  be of no help in the confirmation of diagnosis?
a) Cardiac Troponins
b) Serum myoglobin
c) Lactate dehydrogenase
d) Creatine Phosphokinase-MB(CPK-MB)
19. Which out of the following co enzymes takes part in hydrogen transfer reactions in the electron transport chain-
a) Tetrahydrofolate
b) Methyl Cobalamine
c) Coenzyme Q
d) Biotin
20. One out of the following enzymes has absolute specificity for its substrate; choose the correct option-
a) Urease
b) Carboxypeptidase
c) Pancreatic lipase
d)Lipoprotein lipase
21. Regarding conversion of CO2  into HCO3- in erythrocytes catalyzed by the enzyme carbonic anhydrase, which of the following acts as a substrate(s)?
A Sunlight
B H2O
C Glucose
D H2CO3-
22. A competitive inhibitor has the following effect on a Limeweaver-Burke (double reciprocal) Plot.
(A) It moves the entire curve to the right.
(B) It moves the entire curve to the left.
(C) It changes the y-intercept.
(D) It changes the x-intercept.
(E) It hs no effect on the slope.
23. Cyanides are extremely powerful cell’s poison which can cause death of the human body. Which enzyme blocking in tissue respiration is basic in this action?
(A) Catalase
(B) Superoxide dismutase
(C) Cytochrome oxidase
(D) Hemoglobin reductase
(E) Glucose-6-phosphatdehydrogenase
24. A doctor, before to appoint protein's parenteral nutrition to exhausted patient, appointed to define the electrophoretic spectrum of blood albumens. What physical and chemical properties of albumens is this method based on?
(A) Optical activity
(B) Viscidity
(C) Inability to denaturation
(D) Hydrophilic properties
(E) Presence of charge
25. Patient suffers from acute pancreatitis. What medicines should be prescribed to avoid autolysis of pancreas?
(A) Amylase
(B) Activators of proteases
(C) Trypsin
(D) Chimotripsine
(E) Inhibitors of proteases
26. Which of the following compounds would be useful as a chemotherapeutic agent designed to inhibit synthesis of purine nucleotides?
(a)Allopurinol.
(b)5-fluorouracil.
(c)Methotrexate.
(d) Sulfanilamide
27. The patient has symptoms of pellagra. During interrogation it became known that throughout long time he ate mainly corn and little meat. What became the cause of pellagra?

(A) Deficiency proline in corn

(B) Deficiency tyrosine in corn
(C) Deficiency tryptophan in corn
(D) Deficiency alanine in corn
(E) Deficiency histidine in corn
28. The doctor advises to use half-cooked liver in ratio of the patient during treatment of pernicious anemia. What vitamin presence in this product will have medical effect?

(A) Vitamin b12

(B) Vitamin В1
(C) Vitamin В2
(D) Vitamin C
(E) Vitamin Н
29. At the patient frequent bleedings from internal organs and mucous membranes are observed. The analysis has defined insufficiency of hydroxyproline and hydroxylysine as a part of collagenic fibres. Lack of what vitamin does bring disturbance in the process of hydroxylation of these aminoacids?
(A) Vitamin K
(B) Vitamin A
(C) Vitamin Н
(D) Vitamin C
(E) Vitamin РР
30. Pyruvate concentration in the patient’s urine has increased 10 times from normal amount. What vitamin deficiency can be the reason of this change:

(A) Vitamin B6

(B) Vitamin A
(C) Vitamin E
(D) Vitamin C
(E) Vitamin B1
31. Enzymes catalyze reactions by
A. Increasing the free energy of the system so that the change in free energy is positive
B. Increasing the free energy of the substrate so that it is greater than the free energy of the product
C. Changing the equilibrium constant for the reaction
D. Decreasing the free energy of activation
32. The rate-determining step of Michaelis Menten kinetics is
A. the complex formation step
B. the complex dissociation step to produce product
C. the product formation step
D. Both (a)and(c)
33. Which statement is false about covalent modification?
A) It is reversible.
B) It is slower than allosteric regulation.
C) It involves protein kinases.
D) Phosphorylation is a common covalent modification.
34. To which enzyme LDH belongs to
(A) Transferase
(B) Isomerase
(C) Lipase
(D) Oxidoreductase
(E) Hydrolase
35. Twelve hours after an acute attack of retrosternal pain in the patient presented a jump of aspartate aminotransferase activity in his blood serum. What pathology is this deviation typical for?
A Viral hepatitis
B Myocardium infarction
C Collagenosis
D Diabetes mellitus
E Diabetes insipidus
36. The previous diagnosis was made for the patient: myocardium infarction. Special feature of this pathology is the substantial increase in the blood serum of activity for:
A. Catalase
B. Glucose-6-phosphate dehydrogenase
C. Alpha-amylase
D. Arginase
E. Creatine phosphate kinase
37. The determination of this enzyme activity in the urine is diagnostic test that is used for patients under acute pancreatitis to prove it. Name this enzyme:
A. Aldolase
B. Amylase
C. Lactatedehydrogenase
D. Creatine phosphokinase
E. Alanine aminopeptidase
38. The patient suffers from retrosternal pain from the left, the sweating and palpitation is observed for him, too. Choose enzymes whose activity is in need to determine in the blood to prove diagnosis: myocardium infarction:
A. AST, CPK, LDH1
B. alpha-Fetoprotein, Aldolase, CPK
C. Acidic phosphatase, LDH5, LDH4
D. amylase, alkaline phosphatase, ALT
E. ALT, aldolase, LDH4
39. Special growing factor is in need for tumor cell. Its destruction is made proposed enzyme used for leucosis treatment:
(A) . Asparaginase
(B) . Succinate dehydrogenase
(C) . Aspartate aminotransferase
(D) Citrate synthase .
(E) Glutaminase
40. The pharmaceutical preparation Asparaginase is used for the treatment of leucosis. Find out its mechanism of action:
A. Protein synthesis stimulation
B. Asparagine synthesis
C. Glutamine synthesis
D. Glutamine desruction
E. Asparagine degradation
41. Milk digestibility is improved by using
A. RNase
B. lactase
C. β-amylase
D. none of these
In the figure below, the solid line shows the dependence of the rate of an enzyme catalyzed reaction v (μmol/min) as a function of the substrate concentration [S] (mM).  Also shown (dotted line) is the dependence of the rate on substrate concentration in the presence of an inhibitor (at a concentration of 2 mM).  Questions 42-44 refer to this figure.

42 Regarding the activity of the enzyme in the absence of the inhibitor (solid line), which of the following conclusions is correct?
A) The Vmax of the enzyme is 0.5 μmol/min.
B) The Km of the enzyme is 2 mM.
C) When [S] = 2 mM, v = 2 μmol/min.
D) Vmax/Km = 0.5 μmol/min (mM)-1
E) When [S] = 1 mM, v = 1 μmol/min.
43 In the presence of the inhibitor (dotted line), the Km' (apparent Km) of the enzyme, in units of mM, is:
A) 0.25
B) 0.5
C) 1.0
D) 2.0
E) 4.0
44 On the basis of the graphs shown above, which of the following statements correctly describes the nature of the inhibitor/inhibition?
A) The inhibitor is competitive.
B) The inhibitor is non-competitive.
C) The inhibitor acts as a positive effector.
D) The inhibitor is likely to bind to a site distinct from the active site of the enzyme.
E)  The inhibitor is likely to act as an allosteric effector.
45. Sulfonamide preparation was prescribed for the patient suffered from sore throat. Antimicrobial effect of this preparation is associated with the damage of folic acid synthesis. Name compound that competes with sulfonamide to be attach to active center of enzyme:
A. Glutamic acid
B. Citric acid
C. Ubiquinone
D. Succinate
E. Para-amino benzoic acid

I. Connect vitamin and sigh of its deficiency
1. B1
A. Decreased vision in half-dark
2. B2
B. Symmetric dermatitis
3. A
C. Increased homocysteine, anemia
4. PP
D. Redness, swelling of the mouth corners
5. B12
E. Increased pyruvate in blood

II. Which vitamin deficiency is associated with Neural tube defects?

III. Patient who smokes everyday ½  pack of cigarettes suffers from shortness of breath. Blood test revealed decrease in functional protein, which are produced by liver (lipoprotein lipase, pseudocholine esterase activities). What may be reason of liver problem and embolia? What drugs should be prescribed?





1. In adults, a severe deficiency of vitamin D causes?
a. Night blindness
b. Osteomalacia
c. Rickets
d. Osteogenesis imperfecta
e. Osteopetrosis
2. Which of the following is not a mechanism for altering the flux of metabolites through the rate-determining step of a pathway?
A. Allosteric control of the enzyme activity
B. Block active sites
C. Genetic control of the enzyme concentration
D. Covalent modification of the enzyme
3. Riboflavin deficiency causes
(A) Cheilosis
(B) Loss of weight
(C) Mental deterioration
(D) Dermatitis
4. Pantothenic acid is a constituent of the coenzyme involved in
(A) Decarboxylation
(B) Dehydrogenation
(C) Acetylation
(D) Oxidation
5. A cofactor required in oxidative decarboxylation of pyruvate is
(A) Lipoic acid
(B) Pantothenic acid
(C) Biotin
(D) Paraaminobenzoic acid
6. Thiamin diphosphate is required for oxidative decarboxylation of
(A) α-ketoacids
(B) α-Amino acids
(C) Fatty acids
(D) All of these
7. Riboflavin deficiency can cause
(A) Peripheral neuritis
(B) Diarrhea
(C) Angular stomatitis
(D) None of these
8. Coenzyme A is required for catabolism of
(A) Leucine
(B) Isoleucine
(C) Valine
(D) All of these
9. Biotin is a coenzyme for
(A) Pyruvate carboxylase
(B) Acetyl CoA carboxylase
(C) Propionyl CoA carboxylase
(D) All of these
10. Non-competitive inhibitor of an enzyme catalyzed reaction
A. decreases Vmax
B. binds to ES
C. both (a) and (b)
D. can increase reaction velocity in rare cases
11. If an enzyme is described by the Michaelis-Menten equation, a competitive inhibitor will:
A. decrease the Km and decrease the Vmax
B. decrease the Km, but not the Vmax
C. always just change the Vmax
D. increase the Km but not change the Vmax
12. Rice polish contains vitamin:
(A) Riboflavin
(B) Niacin
(C) Thiamine
(D) Vitamin B12
13. Steroidal prohormone is
(A) Vitamin A
(B) Vitamin C
(C) Vitamin D
(D) None of these
14. Patient with carcinoma has the insufficiency of vitamin В5, serotonin concentration at blood is extremely increased. What is the reason of this state?
(A) Infringement of serotonin metabolism in organism
(B) Tryptophan mainly turns in serotonin
(C) Alimentary deficiency of vitamin РР
(D) Increased use of vitamin РР
(E) Serotonin promotes reduction of vitamin РР in an organism
15. At woman for a long time is on a diet with cleared rice, polyneuritis (illness beriberi) was diagnosed. What vitamin insufficiency at food leads to development of this disease?
(A) Thiamin
(B) Ascorbic acid
(C) Pyridoxine
(D) Folic acid
(E) Riboflavin
16. The patient has symptoms of diarrhea, dementia and dermatitis because of wrong diet. Lack what of vitamin causes this state?
(A) Vitamin В1
(B) Vitamin pp
(C) Vitamin В2
(D) Vitamin C
(E) Vitamin B12
17. Choose the incorrect statement about Active Site of an enzyme-
a) The active site is a three-dimensional pocket
b) The active site takes up a large part of the total volume of an enzyme
c) Substrates are bound to enzymes by multiple weak attractions
d) The specificity of binding depends on the precisely defined arrangement of atoms in an active site.
18. A 60-year-old chronic alcoholic was brought to the hospital with complaints of protuberant abdomen (ascites) and edema feet. He also had history of hemorrhages.  Blood biochemistry revealed: increased serum transaminases, low serum total proteins, albumin and a prolonged prothrombin time. Urine analysis was normal. What could be the possible diagnosis?
a) Renal failure
b) Protein malnutrition
c) Cirrhosis of liver
d) Heart failure
19. The activities of many enzymes, membrane transporters and other proteins can be quickly activated or inactivated by phosphorylation of specific amino acid residues. This regulation is called
a) Allosteric modification
b) Covalent modification
c) Induction
d) Repression
20. A 54-year–old male was rushed to emergency when he collapsed in the middle of a business meeting. Examination revealed excessive sweating and high blood pressure. ECG chest was conclusive of Acute Myocardial infarction. Which biochemical investigation out of the followings would be of no help in the confirmation of diagnosis?
a)  Cardiac Troponins
b) Serum myoglobin
c) Lactate dehydrogenase
d) Creatine Phospho kinase-MB(CPK-MB)
21. A 56- year- old female presents with difficulty opening her eyelids, as well as inability to raise herself from sitting position. She is diagnosed with “myasthenia gravis”, a disease of extreme fatigue, due to decreased concentration of Acetylcholine in her muscles. She has been prescribed physostigmine, a drug that increases the amount of available Acetylcholine, by competitively inhibiting acetylcholinesterase. Which of the following statements is not true of competitive inhibitors?
A) Vmax remains the same
B) Apparent  Km in increased
C) Inhibitor is a structural analogue of the substrate
D) Inhibitor binds covalently to the enzyme
E) Increasing concentration of substrate can reverse the changes
22.Which of the following is a sulphur-containing amino acid that contains a disulphide bond (-S-S-)?
A Serine
B Methionine
C Cysteine
D  Cystine
23. There is alfa-amylase, capable to cleave nutritive in saliva. What substrates of this enzyme?
(A) Nucleoproteins
(B) Lipids
(C) Simple proteins
(D) Carbohydrates
(E) Chromo proteins
24. A 50-years-old man experiences strong stress. The concentration of adrenalin and Noradrenalin was sharply increased in blood. What enzymes catalyze its inactivation process?
(A) Peptidase
(B) Glycosidase
(C) Monoamine oxidase
(D) Carboxylase
(E) Thyrosinase
25. Adult hemoglobin (HbA) – is a protein, which is formed by two alpha- and two beta-peptide chains. What name has this structure of protein?
(A) Tertiary
(B) Quaternary
(C) Secondary
(D) Primary
26. Hem synthesis starts from glycine and succinyl-S-CoA interaction with help of enzyme aminolevulinate synthetase. This enzyme activity is inhibited by the terminal metabolic product – hem. Name the inhibition type:
(A) Feedback inhibition
(B) Uncompetitive regulation
(C) Non-competitive inhibition
(D) Limited proteolysis
(E) Competitive inhibition
27. Patient has diarrhea, dementia and dermatitis. Specify absence of what vitamin is the cause of this state.
(A) Ascorbic acid
(B) Niacin
(C) Folic acid
(D) Biotin
(E) Rutin
28. Most participants of Magellan expedition to America died from avitaminosis. This disease debuted with general weakness, subcutaneous hemorrhages, falling of teeth, gingival hemorrhages. What is the name of this avitaminosis?
(A) Biermer's anemia
(B) Pellagra
(C) Rickets
(D) Polyneuritis (beriberi)
(E) Scurvy
29. For treatment of malignant tumors methotrexate (structural analogue of Folic acid) is prescribed which is the competitive inhibitor of dehydrofolate reductase and consequently suppresses synthesis of:
(A) Glycerophosphates
(B) Monosaccharides
(C) Fatty acids
(D) Nucleotides
(E) Glycogen
30. According to clinical symptoms, pyridoxal phosphate was prescribed to the patient. For correction of what processes this medicine is recommended?
(A) Deamination of purine nucleotides
(B) Oxidative decarboxylation of keto-acid
(C) Transamination and decarboxylation of amino acids
(D) Synthesis of purine and pyrimidine nucleotides
(E) Synthesis of proteins
31. A catalyst can promote product formation during a chemical reaction by _____.
(a) lowering the activation energy barrier.
(b) stabilizing the transition state.
(c) positioning reactants in the correct orientation.
(d) bringing reactants together.
(e) all of the above
32. Which of the following is characteristic of an enzyme catalyst?
(a) It positions reactants in the correct orientation.
(b) It lowers the activation energy barrier.
(c) It binds the transition state tighter than the substrate.
(d) all of the above
33. NAD+, FAD, and FMN are all cofactors for:
A. Oxidoreductases
B. Transferases
C. Hydrolases
D. Ligases
34. Invasive properties of pathogenic microorganisms are due to next enzymes
(A) Hydrolases
(B) Lyases
(C) Ligases
(D) Oxidoreductases
(E) Transferases
35. Marked increase of activity of MB-form of CPK (creatine phosphokinase) and LDH-1 were revealed on the examination of the patient's blood. What is the most likely pathology?
A Cholecystitis
B Hepatitis
C Rheumatism
D Pancreatitis
E Miocardial infarction
36. The investigation of diseased person’s blood has revealed the excess increase of MB-isozyme of CPK (creatine phosphate kinase) and LDH1. Propose the probable pathology:
A. Myocardium infarction
B. Hepatitis
C. Rheumatism
D. Pancreatitis
E. Cholecystitis
37. The sick person was admitted to the hospital with previous diagnosis – acute pancreatitis. Name enzyme, whose activity must be determined in the blood serum and urine to prove this diagnosis:
A. Alpha-amylase
B. AlAT
C. AsAT
D. Lactate dehydrogenase
E. Choline esterase
38. Keloids were remained on patient’s body after burns. What enzyme-preparation may be used for their resorption?
A. Asparaginase
B. Nigedase
C. Galactozidase
D. Streptolidase
E. Lidase
39. This enzyme is prescribed as preparation for treatment of purulent wounds. Name it:
A. Alkalic phosphatase
B. Amylase
C. Acidic phosphatase
D. Trypsin
E. Arginase
40. The patient with myocardium infarction was prescribed fibrinolytic drug “Streptodekase” created using the linkage of enzyme with water- soluble polysaccharide template produced by method:
A. Autolysis
B. Ultracentrifugation
C. Electrophoresis
D. Enzyme mobilization
E. Extraction
41. Which one of the following graphs shows the effect of pH on the reaction velocity of a typical enzyme?

42. Consider the following Lineweaver-Burk plot for the following question. The solid line indicates data observed in the absence of any inhibitor. The dotted lines labeled 1 and 2 indicate data observed in the presence two different inhibitors. Which of the following represents the kinetic values of the enzyme in the presence of a non-competitive inhibitor?

     Km   Vmax
A) 0.5    5
B)  -2      0.4
C) 1        2.5
D) 0.5     2.5
43. Hem synthesis starts from glycine and succinyl-SCoA interaction with (aminolevulinate synthetase help. It is inhibited by the terminal metabolic product – hem. Name the inhibition type:
A. Feedback inhibition
B. Uncompetitive regulation
C. Non-competitive inhibition
D. Limited proteolysis
E. Competitive inhibition
44. Some pharmaceutical preparations containing ions of arsenic and mercury are used in medical practice. Name type of inhibition of enzyme activity by these metal ions:
A. Reversible
B. Non-competitive
C. Uncompetitive
D. Competitive
E. Allosteric
45. Name factor of medium which can influence the charge of functional groups in active site of enzyme molecule:
A. Temperature of medium
B. Activator content in the medium
C.  pH of the medium
D. Pressure
E. Allosteric inhibitor content in the medium

I Connect organ and enzyme which can be used to detect disease in that organ
1.LDH1
A. Liver
2.Ala Transfarse
B. Skeletal muscles
3.Acid phosphatase
C. Heart
4.Regan Alac phosphatase
D. Cancer (ovary, uterus)
5.Aldose
E. Prostatic cancer

II Why is it said that Niacin and vitamin D are not true vitamins?

III A 56 – year-old male on Isoniazid therapy for tuberculosis has developed rashes on the exposed parts of the body. What is the probable cause for these rashes?



1. One manifestation of vitamin A deficiency is
(A) Painful joints
(B) Night blindness
(C) Loss of hair
(D) Thickening of long bones
2. Scurvy is caused due to the deficiency of
(A) Vitamin A
(B) Vitamin D
(C) Vitamin K
(D) Vitamin C
3. Magenta tongue is found in the deficiency of the vitamin
(A) Riboflavin
(B) Thiamin
(C) Nicotinic acid
(D) Pyridoxine
4. The precursor of CoA is
(A) Riboflavin
(B) Pyridoxamine
(C) Thiamin
(D) Pantothenate
5. Which ion is a component of B12 core ring
(A) Cobalt
(B) Manganese
(C) Magnesium
(D) Iron
6. Loss of thiamin can be decreased by using
(A) Unpolished rice
(B) Parboiled rice
(C) Whole wheat flour
(D) All of these
7. Pellagra preventing factor is
(A) Thiamin
(B) Riboflavin
(C) Niacin
(D) Pyridoxine
8. Pyridoxal phosphate is a coenzyme for
(A) Glutamate oxaloacetate transaminase
(B) Glutamate pyruvate transaminase
(C) Tyrosine transaminase
(D) All of these
9. Folic acid contains
(A) Pteridine
(B) p-Amino benzoic acid
(C) Glutamic acid
(D) All of these
10. Daily requirement of vitamin C in adults is about
(A) Potassium
 (B) Iodine
 (C) Iron
 (D) None of these
11. The symptoms of scurvy are
(A) Poor healing of wounds
(B) Loosening of teeth
(C) Anemia
(D) All of these
12. Symptoms of pellagra are
(A) Dermatitis and diarrhea only
(B) Dermatitis and dementia only
(C) Diarrhea, dermatitis and dementia
(D) Diarrhea and elements only
13. Antirickets vitamin is
(A) Vitamin A
(B)  Vitamin D
C) Vitamin E
(D)Vitamin K
14. After epileptic attack the baby was examined by the podiatrist. Baby was given artificial meal. Dermatitis was diagnosed. After laboratory tests the decrease of alanine and aspartate aminotransferase level activity of erythrocytes was detected. What vitamin insufficiency can be detected?
(A) Cobalamin
(B) Ascorbic acid
(C) Pyridoxine
(D) Riboflavin
(E) Calciferol
15. At the patient with frequent bleedings from an internal organs and mucous membrane, proline and lysine as a part of collagen’s fibers are found out. What vitamin absence causes hydroxylation of proline and lysine?
(A) Thymine
(B) B1
(C) A
(D) C
(E) E
16. Hydroxyproline is the important amino acid in the structure of collagen. Which vitamin does help in formation of this amino acid by hydroxylation of proline?
(A) B2
(B) D
(C) B1
(D) C
(E) B6
17. Any of the following processes except one are involved at the active site of an enzyme to accelerate the rate of reaction-
a) Catalysis by Bond Strain
b) Catalysis by Proximity and Orientation
c) Non covalent catalysis
d) Acid base catalysis     
18. A 2-weeks –old child was brought to the emergency. The parents were fearful that the child had been given some poison as they noted black discoloration on the diaper. A diagnosis of Alkaptonuria was made and the child was given Vitamin C as a supplement. Alkaptonuria occurs due to reduced activity of homogentisic acid oxidase enzyme. What is the role played by vitamin C in this defect?
a) Acts as an oxidant
b)Acts as a coenzyme
c) Acts as an inducer
d) Acts as a positive allosteric modifier
19. Glycogen phosphorylase, which mobilizes glycogen for energy, requires which of the followings as a cofactor?
a) Pyridoxal phosphate
b) Tetrahydrofolate
c) Adenosyl Cobalamin
d) Coenzyme A
20. A 42-year-old obese female presented to the emergency center with complaints of worsening nausea, vomiting, and abdominal pain. Her pain was in the mid epigastric area and right upper quadrant. Blood biochemistry revealed high serum amylase level. What is the probable diagnosis for this patient?
a) Viral hepatitis
b) Acute Pancreatitis
c) Renal colic
d) Acute gastritis
21. Amino acid that contains a double ring in its structure: 
A Proline
B Tyrosine
C Tryptophan
D Phenylalanine
22. An allosteric inhibitor of an enzyme usually
(A) binds to the active site.
(B) participates in feedback regulation.
(C) denatures the enzyme.
(D) causes the enzyme to work faster.
(E) is a hydrophobic compound.
23. Aspirin owns a anti-inflammatory action, as inhibit cyclooxygenase activity. The level of what bioactive molecules will go down?
(A) Prostaglandins
(B) Leukotrienes
(C) Catecholamines
(D) Biogenic amines
(E) Iodothyronines
24. Cation glycoproteins are the basic components of saliva of parotid glands. What amino acids creates their positive charge?
(A) Aspartate, glutamate, glycine
(B) Lysine, arginine, histidine
(C) Aspartic acid, arginine, glutamic acid
(D) Glutamic acid, valine, leucine
(E) Cysteine, glycine, praline
25. Succinate dehydrogenase catalyzes the dehydrogenation of succinate. Malonic acid is used to interrupt the action of this enzyme. Choose the inhibition type:
(A) Allosteric
(B) Competitive
(C) Non-competitive
(D) Dephosphorylation
(E) Limited proteolysis
26. During various diseases level of active forms of oxygen increases extremely that leads to destruction of cellular membranes. For prevention of it antioxidants are used. Strong natural antioxidant is:
(A) Glucose
(B) alpha-tocopherol
(C) Vitamin D
(D) Fatty acids
(E) Glycerin
27. People, who suffers from alcoholism, receive main part of calories with alcoholic beverages. They can have a characteristic insufficiency of thiamine (a syndrome of Wernicke), which causes a nervous system functions infringement, psychoses, memory loss. What enzyme activity is decreased in this case?
(A) Transaminase
(B) Alcohol dehydrogenase
(C) Pyruvate dehydrogenase
(D) Aldolase
(E) Hexokinase
28. The oxidative decarboxylation of alpha-ketoglutarate is broken because of vitamin В1 deficiency. Synthesis of what coenzyme is broken?
(A) Nicotinamide adenine dinucleotide (NAD)
(B) Thiamine pyrophosphate (TPP)
(C) Flavin adenine dinucleotide (FAD)
(D) Lipoic acid (LA)
(E) Coenzyme A
29. Hydroxylation of endogenous substrates and xenobiotics requires a donor of protons. Which of the following vitamins can play this role?
(A) Vitamin C
(B) Vitamin E
(C) Vitamin P
(D) Vitamin A
(E) Vitamin B6.
30. Which of the following statements concerning the effect of temperature change on an enzyme-catalyzed reaction is correct?
A) An increase in temperature can stop the reaction by denaturing the enzyme.
B) An increase in temperature can increase the reaction rate by increasing the speed at which molecules move.
C) An increase in temperature to the optimum temperature maximizes reaction rate.
D) more than one correct response
E) no correct response
31. An apoenzyme
A. Includes non-protein compounds such as metal ions
B. Consists of complex organic structures which may be classified as activation-transfer coenzymes or oxidation-reduction coenzymes
C. Is the protein portion of the enzyme without the cofactors
D. None of the above
32. A competitive inhibitor of an enzyme works by
A. fitting into the enzyme's active site
B. fitting into the allosteric site of the enzyme
C. attaching itself to the substrate, thereby preventing the enzyme from contacting with substrate
D. increasing the activation energy of the enzyme-catalyzed reaction
33. In a Lineweaver-Burk Plot, competitive inhibitor shows which of the following effect?
A. It moves the entire curve to right
B. It moves the entire curve to left
C. It changes the x-intercept
D. It has no effect on the slope
34. Protein kinases are enzymes that act on other enzymes by adding phosphates groups. When the enzyme is phosphorylated, it changes its activity (it becomes activated or deactivated depending on the enzyme). This regulatory mechanism of enzymatic activity is called:
A) Allosteric Control
B) Competitive inhibition
C) Covalent Modification
D) Isozymes Modification
E) Zymogen activation
35. A patient presents high activity of LDH1, LDH2, aspartate aminotransferase, creatine phosphokinase. In what organ (organs) is the development of a pathological process the most probable?
A In the heart muscle (initial stage of myocardium infarction)
B In skeletal muscles (dystrophy, atrophy)
C In kidneys and adrenals
D In connective tissue
E In liver and kidneys
36. It was revealed acute pancreatitis in patient using biochemical investigation of his blood plasma. Find out biochemical test which can prove this diagnosis:
A. Acidic phosphatase activity
B. Amino transferases activity
C. Amylase activity
D. Creatinine content
E. Creatine phosphate kinase activity
37. Name enzymes whose activity is in need to determine in the blood plasma to diagnose and to predict the development of disease for the patient with cardiac pathology:
A. PDH, MDH, KGDH
B. CPK (creatine phosphokinase), AlAT, AsAT
C. Arginase, peptidase, acidic phosphatase
D. Lysozyme, citrate synthase, aldolase
E. Neuraminidase, hexokinase, pyruvate kinase
38. The preparation named “Lidase” is used in clinics for resorption of keloids and hematomas after burns and surgery operations. Name substrate for this enzyme preparation:
(A) Hyaluronic acid
(B) Dermatan sulfate
(C) Heparin
(D) Keratan sulfate
(E) Chondroitin-4-sulfate
39.Pathogenic microorganisms during their entering and reproduction in human tissues produce different enzymes to help them in these actions. Find out those enzymes:
(A) Oxidase, Catalase
(B) Lipase, Ligase
(C) Transferase, nuclease
(D) Esterase, protease
(E) Hyaluronidase, Lecithinase
40. Five enzymes (LDH4, LDH5, AlAT, gamma-glutamyl transferase, carbamoyl ornithine transferase) activities are increased in blood plasma of patient. Name organ (tissue) whose damage is checked:
A. Liver
B. Heart
C. Lungs
D. Kidney
E. Pancreas
41. Asparaginase is used to reduce the level of asparagine in the blood in one treatment for leukemia. Which isoform of asparaginase would be most useful if the patient’s blood asparagine level is 0.2mM?
         Km       Vmax
A) 0.1mM; 0.5 mM/hr
B) 0.2mM; 0.1 mM/hr
C) 0.2mM; 0.5 mM/hr
D) 2.0mM; 0.1 mM/hr
E) 0.1mM; 0.1 mM/hr
42. Which of the diagrams illustrates the way in which the rate of an enzyme-controlled reaction depends on substrate concentration?

43. The amino acid sequence of an enzyme was determined to have a genetic mutation resulting in the amino acid change cysteine  proline that maps to the location on the structure to the right highlighted by a box. The active site is designated by a circle which contains a zinc cofactor shown as a black sphere and an inhibitor shown as white sticks. Of the following options, what is the most likely effect of the mutation?

A) The mutant amino acid will directly interfere with catalysis.
B) The mutant amino acid is too far away to have any effect on the active site.
C) The mutant amino acid will alter interactions affecting the overall 3D enzyme structure.
D) The mutant amino acid will change the substrate specificity of the enzyme.
E) The enzyme will no longer bind its cofactor.
44. Heavy metal ions are very toxic. They block SH-groups that are placed in active centers of enzymes. Name the type of enzyme inhibition for heavy metal ions:
A. Competitive
B. Allosterically
C. Non-competitive
D. Uncompetitive
E. Suicide
45. The action of competitive inhibitor may be prevented by the:
A. Increase of enzyme concentration
B. The use of metal ion in the medium
C. Increase of substrate concentration
D. The use of allosteric activator
E. The removal of the product from the medium

I. Combine enzyme and its class
1. Oxidoreductase
A. DNA-polymerase
2. Transferase
B. LDH
3. Hydrolase
C. Pepsin
4. Ligase
D. sGOT
5. Lyase
E. Aldolase

II. Name the vitamin that acts as a coenzyme for the post translational modifications of prothrombin.

III. A 5-year-old child with a previous fracture right foot had a serum Alkaline Phosphatase (ALP) of 840 U/L (High),  a serum phosphate of 3.5 mg/dL (Normal),and a serum γ-glutamyl transferase(GGT) of 30 U/L (Normal). There was no history of fever or any other medical illness.
After the clotted blood was spun down in the test tube, the serum was visibly hemolyzed owing to difficulty in obtaining the specimen. The physical examination of the child was unremarkable.
Why is the normal range of ALP higher in children than in adults?
What is the significance of a hemolyzed serum sample and the elevated serum ALP?
What is the most likely cause of the elevated ALP?






1. Both Wernicke’s disease and beriberi can be reversed by administrating
(A) Retinol
(B) Thiamin
(C) Pyridoxine
(D) Vitamin B12
2. Increased glucose consumption increases the dietary requirement for
(A) Pyridoxine
(B) Niacin
(C) Biotin
(D) Thiamin
3. Pellagra is caused due to the deficiency of
 (A) Ascorbic acid
(B) Pantothenic acid
(C) Pyridoxine
 (D) Niacin
4. Pyridoxal phosphate is central to
(A) Deamination
(B) Aminations
(C) Carboxylation
(D) Transamination
5. Both folic acid and methyl cobalamin (vitamin B12) are required in
(A) Deamination of serine
(B) Deamination of threonine
(C) Conversion of pyridoxal phosphate to pyridoxamine phosphate
(D) Methylation of homocysteine to methionine
6. NADP is required as a coenzyme in
(A) Glycolysis
(B) Citric acid cycle
(C) HMP shunt
(D) Gluconeogenesis
7. A vitamin which can be synthesized by human beings is
(A) Thiamin
(B) Niacin
(C) Folic acid
 (D) Cyanocobalamin
8. Conversion of folate into tetrahydrofolate requires
(A) NADH
(B) NADPH
(C) FMNH2
(D) FADH2
9. Vitamin C activity is present in
(A) D-Ascorbic acid
(B) D-Dehydroascorbic acid
(C) L-Ascorbic acid
(D) Both A and B
10. The egg injury factor in raw egg white is
(A) Biotin
(B) Avidin
(C) Albumin
(D) Calcium salts
11. The following vitamin is involved in coenzyme function in transaminations:
(A) Nicotinamide
(B) Pyridoxine
(C) Thiamine
(D) Riboflavin
12. One of the main functions of Vitamin K is the cofactor for
(A) Carboxylase for the formation of γ-carboxyglutamate
(B) Methylation by S-adenosyl methionine
(C) Carboxylation by biotin
(D) One carbon transfer by tetrahydrofolate
13. Chose enzyme with absolute specifity
A. Chymotrypsin
B. Hexokinase
C. Pepsin
D. Lipase
E. Diastase
14. Increased concentration of pyruvate is detected at the patient’s blood and urine. What avitaminosis is observed at the patient?
(A) Avitaminosis B1
(B) Avitaminosis Е
(C) Avitaminosis В3
(D) Avitaminosis В6
(E) Avitaminosis В2
15. How non-competitive inhibitor influence on curve position in Lineweaver -Burk plot
A. Move whole curve to write
B. Change y-cross position
C. Move whole curve to left
D. Change x-cross position
16. A given substrate may be acted upon by several different enzymes, each of which uses the same substrate(s) and produces the same product(s). The individual members of a set of enzymes sharing such characteristics are known as-
a) Group specific enzymes
b) Isoenzymes
c) Substrate specific enzymes
d) Allosteric enzymes
17. A 67- year-old army officer in good health previously presented with sudden pain in the great toe.  Serum uric acid level was high, and a diagnosis of gouty arthritis was made He was advised bed rest, pain killers and Allopurinol. What is the mechanism of action of Allopurinol in lowering serum uric acid levels?
a) Suicidal inhibition
b) Non-competitive inhibition
c) Allosteric inhibition
d) Feedback inhibition
18. Choose the incorrect statement about Active Site of an enzyme
a) The active site is a three-dimensional cleft
b) The active site takes up a large part of the total volume of an enzyme
c) Substrates are bound to enzymes by multiple weak attractions
d) The specificity of binding depends on the precisely defined arrangement of atoms in an active site.
19. A 60-year-old chronic alcoholic was brought to the hospital with complaints of protuberant abdomen (ascites) and edema feet. He also had history of hemorrhages.  Blood biochemistry revealed – High serum transaminases, low Serum total proteins, Albumin and a prolonged prothrombin time. Urine analysis was normal. What could be the possible diagnosis?
a) Renal failure
b) Protein malnutrition
c) Cirrhosis of liver
d) Heart failure
20. Zinc is a prosthetic component of enzyme(s):
(A) carboxypeptidase
(B) alcoholdehydrogenase
(C) carbonicanhydrase
(D) succinatedehydrogenase
(E) All
21. Non-protein part of enzyme which participate in reaction and covalently bonded with protein part is called
A. apoenzyme
B. prostetic group
C. proenzyme
D. cofactor
E. coenzyme
22. A non-competitive inhibitor of an enzyme catalyzed reaction
(A) binds to the Michaelis complex (ES).
(B) decreases Vmax.
(C) is without effect at saturating substrate concentrations.
(D) can increase reaction velocity in rare cases.
(E) The first and second choices are both correct.
23. At necropsy of a 40-year-old woman the legal expert found that death occurred because of poisoning with cyanides. Blocking of which process is the most probable with the cyanides in this state?
(A) Cytochrome oxidase
(B) Glycogen phosphorylase
(C) Pyruvate carboxylase
(D) Succinate dehydrogenase
(E) Glucose-6- phosphate dehydrogenase
24. Proteins presence in a solution can be found out by means of color reactions. Which one of listed reactions proves the negative result during full proteins hydrolysis?
(A) Lead acetate test
(B) Ninhydrin reaction
(C) Xanthoprotein reaction
(D) Biuret reaction
(E) Sakaguchi reaction
25. What is the mode of action of the anticancer drug methotrexate?
a) It inhibits the absorption of folate from the intestine.
b) It inhibits dihydrofolate reductase so inhibiting thymidylate synthesis.
c) It inhibits the secretion of extrinsic factor which is needed for DNA synthesis.
d) It inhibits protein synthesis at the elongation stage.
26. At the young man 20 years old macrocytic anemia has emerged, increased level of methyl malonic acid is registered in urine. It is caused by deficiency of:
(A) Pantothenic acid
(B) Nicotinic acid
(C) Cyanocobalamin
(D) Ascorbic acid
(E) Biotin
27. At the patient of 36 years old who suffers from chronic alcoholism, accumulation of pyruvate is registered in blood, in erythrocytes – transketolase activity is decreased. What coenzymes deficiency causes these changes?
(A) Pyridoxal phosphate
(B) Carboxybiotin
(C) Methyl cobalamin
(D) Thiamine pyrophosphate
(E) Tetrahydrofolate
28. Increased vessels, enamel and dentine destruction at scurvy patients are caused by disorder of collagen maturing. What stage of procollagen modification is damaged during this avitaminosis?
(A) Hydroxylation of proline
(B) Formation of polypeptide chains
(C) Glycosylation of hydroxylysine residues
(D) Removal of C-ended peptide from procollagen
(E) Detaching of N-ended peptide.
29. What is the function of enzymes within living systems?
A) structural elements
B) neurotransmitters
C) catalysts
D) hormones
30. Enzymes have names that
A) always end in -ase
B) always end in -in
C) can end either in -in or -ase
D) can end in either -in or –ogen
31. An allosteric activator
A. increases the binding affinity
B. decreases the binding affinity
C. stabilizes the R state of the protein
D. both (a) and (c)
32. Allosteric enzymes are
A. similar to simple enzyme
B. smaller than simple enzyme
 C. larger and more complex than simple enzyme
 D. smaller than simple enzyme but not complex
33. Which ion activate salivary amylase
(A) Ca2+
(B) Cu2+
(C) Cl-
(D) Mg2+
34. Glucokinase catalyzes the transfer of phosphate group from ATP to glucose. This enzyme is
(A) Lyases
(B) Oxidoreductase
(C) Isomerases
(D) Hydrolases
(E) Transferases
35. 6 hours after the myocardial infarction a patient was found to have elevated level of lactate dehydrogenase in blood. What isozyme should be expected in this case?
A. LDH4
B. LDH1
C. LDH5
D. LDH3
E. LDH2
36. The patient of 47 y.o. with diagnosis myocardium infarction was admitted to reanimation department of hospital. What isozyme of LDH (lactate dehydrogenase) will be elevated first two days in this patient’s blood plasma?
A. LDH1
B. LDH2
C. LDH 3
D. LDH 4
E. LDH 5
37. Name enzyme, whose activity determination in the blood serum is the most informative test at first hours of myocardium infarction development:
A. Creatine phosphate kinase
B. AsAT
C. AlAT
D. LDH
E. Glutamate dehydrogenase
38. The inhibitor for acetylcholine esterase was prescribed as preparation for the treatment of patient. Choose it from the list:
(A) . Aspirin
(B) . Indometacin .
(C) Allopurinol
(D) Sodium dichlorfenak .
(E) Proserin
39. Treatment of patient with purulent wounds is made using dressing with enzyme immobilized on them. Find out this enzyme:
A. Trypsin
B. Arginase
C. Catalase
D. Alkalic phosphatase
E. Acidic phosphatase
40. Trasilol is a preparation to treat acute pancreatitis, and it is found to block activity of special pancreatic enzyme. Choose this enzyme:
A. trypsin
B. Amylase
C. Lipase
D. Elastase
E. Phospholipase A2
41. Refer to the Lineweaver-Burk plot below, showing the kinetic data representing five similar but distinct substrates of a single enzyme. Based on their kinetic parameters, which is the most preferred substrate of the enzyme?

42. In the following diagram, each of the curves P, Q and R represents an enzyme-controlled reaction in one of the following situations:
• with the enzyme uninhibited
• with a non-competitive inhibitor
• with a competitive inhibitor.
Which curve, P, Q or R, represents each situation?
uninhibited enzyme
competitive inhibitor added
non-competitive inhibitor added
43. Lipitor (a statin drug) inhibits the enzyme HMG-CoA Reductase in the pathway of cholesterol biosynthesis via competitive inhibition. Normal kinetic parameters for this enzyme with HMG-CoA (without the drug) are: Km = 8.1 µM and Vmax = 330 pmol min-Which of the following shows the expected changes in the kinetic parameters for HMG-CoA in the presence of the drug?
      Km                      Vmax
A) 8.1 µM          120 pmol min-1
B) 20.8 µM        120 pmol min-1
C) 20.8 µM      330 pmol min-1
D) 8.1 µM          330 pmol min-1
E) 2.3 µM           330 pmol min-1
44. Structure feature for regulatory enzyme usually is the presence of allosteric center in their molecules. Find out its role:
A. It attaches the regulator-substance
B. It attaches the substrate
C. It changes the structure of substrate
D. It helps in dissociation of coenzyme
E. It attaches the coenzyme
45. Name a substance that competes with succinate to be attached to active site of Succinate dehydrogenase:
A. Pyruvic acid
B. Amber acid
C. Malate
D. Lactate
E. alpha-Ketoglutarate

I. Combine enzyme and metal which is the component of this enzyme

1. Alcohol dehydrogenase
A. Fe2+
2. Cytochrome oxidase
B. K+
3. Pyruvate kinase
C. Mg2+
4. Xanthine oxidase
D. Zn2+
5. Hexokinase
E. Mo4+

II The synthesis of which vitamin is inhibited by Sulphonamides?

III. A 44-year-old man who had lost his job because of absenteeism, presented to his physician complaining of loss of appetite, fatigue, muscle weakness, and emotional depression.
The physical examination revealed a somewhat enlarged liver that was firm and nodular, and there was a hint of jaundice in the sclerae and a hint of alcohol in his breath. The initial laboratory profile included a hematological analysis that showed that he had an anemia with enlarged red blood cells (macrocytic). A bone marrow aspirate confirmed the suspicion that he had a megaloblastic anemia because it showed a greater than normal number of red and white blood cell precursors, most of which were larger than normal. Further analyses revealed that his serum folic acid level was1.2 ng/mL (normal 2.5 to20), his serum B12 level was 253 ng/mL (normal 200 to 900), but his serum iron level was normal.
What is the cause of megaloblastic anemia in this patient?




1. Deficiency of vitamin D causes
(A) Rickets and osteomalacia
(B) Tuberculosis of bone
(C) Hypothyroidism
(D) Skin cancer
2. The Vitamin B1 deficiency causes
(A) Rickets
(B) Nyctalopia
(C) Beriberi
(D) Pellagra
3. Niacin is synthesized in the body from
(A) Tryptophan
(B) Tyrosine
(C) Glutamate
(D) Aspartate
4. Biotin is a coenzyme of the enzyme
(A) Carboxylase
(B) Hydroxylase
(C) Decarboxylase
(D) Deaminase
5. Folate as a coenzyme is involved in the transfer and utilization of
(A) Amino group
(B) Hydroxyl group
(C) Single carbon moiety
(D) Amino group
6. Thiamin requirement is greater in
(A) Non-vegetarians
(B) Alcoholics
(C) Pregnant women
(D) Both B and C
7. Which ion is necessary for activity of carbonic anhydrase
A. Cl
B. Zn
C. Mg
D. Mn
E. Fe
8. Riboflavin deficiency symptoms are
(A) Glossitis
(B) stomatitis
(C) Vomiting
(D) Both (A) and (B)
9. Deficiency of vitamin C causes
(A) Beriberi
(B) Pellagra
(C) Pernicious anemia
(D) Scurvy
10. The human species can biosynthesize
(A) Vitamin C
(B) Vitamin B12
(C) Thiamine
(D) Niacin
11. Deficiency of Vitamin A leads to
(A) Rickets
(B) Scurvy
(C) Night blindness
(D) All of these
12. This Vitamin acts as antioxidant:
(A) Vitamin A
(B) Vitamin D
(C) Vitamin E
(D) Vitamin K
13. Treatment of some infectious diseases which are caused by bacteria is based on, sulfanilamide medicines. These medicines block synthesis of the growth factor of bacteria. Choose the mechanism of sulfanilamide’s medicines:
(A) Inhibition of absorption of folic acid
(B) these drugs are antivitamins of paraaminobenzoic acid inhibitor of same enzymes
(C) these drugs take part in oxide-redactions reactions
(D) these drugs are allosteric enzymes of paraaminobenzoic acid
14. Anticoagulant pelentan was prescribed to the patient with thromboembolia. What vitamin antagonist is this compound?
(A) Vitamin C
(B) Vitamin E
(C) Vitamin A
(D) Vitamin D
(E) Vitamin K
15. Patient suffers from diarrhea, dementia and dermatitis. At the anamnesis is known that the basic foodstuff of the patient is corn. These infringements relate to malnutrition of vitamin:
(A) Vitamin В1
(B) Vitamin pp
(C) vitamin В2
(D) vitamin В9
(E) vitamin В8
16. One out of the following enzymes has absolute specificity for its substrate; choose the correct option
a) Urease
b) Carboxypeptidase
c) Pancreatic lipase
d) Lipoprotein lipase
17. A competitive inhibitor of an enzyme is usually:
(A) a highly reactive compound.
(B) a metal ion such as Hg2+ or Pb2+.
(C) structurally like the substrate.
(D) water insoluble.
(E) a poison
18. In adjustment of enzymes activity an important place belongs to their post synthetic covalent modification. What from the noted mechanisms is used to control glycogen phosphorylase and glycogen synthase activity?
(A) Methylation
(B) Phosphorylation-dephosphorylation
(C) Adenyle addition
(D) Limited proteolysis
(E) ADP-ribosylation
19. The biological oxidation and deactivation (detoxication) of xenobiotics are realized by
hem-containing enzymes. Which metal is a required component of these enzymes?
(A) Mg
(B) Zn
(C) Co
(D) Fe
(E) Mn
20. Aspirin has anti-inflammatory and analgesic action, as inhibit the biosynthesis of prostaglandins. What enzyme is inhibited by aspirin?
(A) Decarboxylase
(B) Dehydrogenase
(C) Hydroxylase
(D) Cyclooxygenase
(E) Deaminase
21. Proteins presence in a solution can be found out by means of color reactions. Which one of listed reactions proves the negative result during full proteins hydrolysis?
(A) Lead acetate test
(B) Ninhydrin reaction
(C) Xanthoprotein reaction
(D) Biuret reaction
(E) Sakaguchi reaction
22. Treatment of some infectious diseases which are caused by bacteria is based on, sulfanilamide medicines. These medicines block synthesis of the growth factor of bacteria. Choose the mechanism of sulfanilamide’s medicines:
(A) Inhibition of absorption of folic acid
(B) these drugs are antivitamins of paraaminobenzoic acid
(C) inhibitor of same enzymes
(D) these drugs take part in oxide-redactions reactions
(E) these drugs are allosteric enzymes of paraaminobenzoic acid
23. At patient, with frequent bleedings in to visceral organs and mucous membranes, in the structure of collagen fibers proline and lysine were found out. Absence of what vitamin causes such infringement of hydroxylation of this amino acid?
(A) Vitamin E
(B) Vitamin C
(C) Vitamin K
(D) Vitamin A
(E) Vitamin D
24. It is known that the collagen molecule contains amino acids (oxyproline, oxylysine). Which one of the listed low substances takes part in hydroxylation of proline and lysine during synthesis?
(A) Asparagine acid
(B) Folic acid
(C) Pantothenic acid
(D) Glutamic acid
(E) Ascorbic acid
25. During parodontosis treatment an antioxidant of a natural and artificial origin is used. Specify, what of natural compounds is used as antioxidant?
(A) Gluconate
(B) Thiamine
(C) Tocopherol
(D) Pyridoxine
(E) Choline
26. If there is insufficiency of thiamine - vitamin В1, bery-bery disease (polyneuritis) and carbohydrate metabolism disorder occur. What metabolite accumulates in blood during these processes?
(A) Malate
(B) Lactate
(C) Succinate Citrate
(D) Pyruvate
27. There is the osteoporosis in the patient with chronic renal failure. What vitamin’s metabolism infringement promotes this disorder?
(A) Vitamin D
(B) Vitamin E
(C) Vitamin A
(D) Vitamin K
(E) Vitamin C
28. Which of the following statements about enzymes or their function is true?
A. Enzymes do not alter the overall change in free energy for a reaction
B. Enzymes are proteins whose three-dimensional form is key to their function
C. Enzymes speed up reactions by lowering activation energy
D. All the above
29. Which of the following statements about allosteric enzymes is CORRECT?
A. The binding of substrate to any active site affects the other active sites
B. The plot of initial velocity vs. substrate concentration is a straight line
C. The Keq of the reaction is increased when allosteric activator is bound
D. The enzymes contain only one polypeptide chain
30. An uncompetitive inhibitor binds to _____.
(a) E
(b) ES
(c) P
(d) a and b
(e) a and c
31. Allosteric modulators seldom resemble the substrate or product of the enzyme. What does this observation show?
 A) Modulators likely bind at a site other than the active site.
B) Modulators always act as activators.
 C) Modulators bind non-covalently to the enzyme.
 D) The enzyme catalyzes more than one reaction.
32. Which statement is false about allosteric regulation?
A. It is usually the mode of regulation for the last step in reaction pathways since this step produces the final product.
B. Cellular response is faster with allosteric control than by controlling enzyme concentration in the cell.
C. The regulation usually is important to the conservation of energy and materials in cells.
D. Allosteric modulators bind non-covalently at sites other than the active site and induce conformational changes in the enzyme.
33. Pyridoxal phosphate is required as a coenzyme in
(A) Transamination
(B) Transsulphuration
(C) Desulphyration
(D) All of these
34. Enzymes which are main to promote biological oxidation
(F) Lyases
(G) Oxidoreductase
(H) Isomerases
(I) Hydrolases
(J) Transferases
35. There is medicine named Teturam used in medical practice for the treatment and prophylaxis of alcoholism, and this preparation is inhibitor of aldehyde dehydrogenase. Accumulation of what compound in the blood of alcoholics will cause the aversion to alcohol under the use of this preparation?
A. Acetic aldehyde
B. Ethanol
C. Malonic dialdehyde
D. Propionic aldehyde
E. Methanol
36. The woman of 50 y.o. with diagnosis myocardium infarction was admitted in the department of intensive therapy. Name the enzyme whose activity will be elevated two days in the blood plasma of this diseased person:
A. Alanine aminotransferase
B. Alanine peptidase
C. Aspartate aminotransferase
D. LDH4
E. LDH5
37. The patient has acute pancreatitis. Name preparation that will be recommended by doctor for the treatment to prevent autolysis of pancreas:
A. Proteases inhibitors
B. Proteases activators
C. Trypsin
D. Chymotrypsin
E. Amylase
38. 46 years old patient’s blood serum creatine phosphate kinase activity was determined, and it was increased in values. Name the pathology that may be discussed for this patient:
(A) Chronic hepatitis
(B) Myocardium infarction .
(C) Hemolytic anemia
(D) Acute pancreatitis .
(E) Renal insufficiency
39. The most informative test for early diagnosis of muscular dystrophies is the increase in the blood plasma of enzyme activity named:
A. AsAT
B. AlAT
C. CPK-3
D. LDH1
E. Hexokinase
40. The degree of liver parenchyma damage may be estimated due to determination in the blood plasma of:
A. Choline esterase activity
B. Amylase activity
C. LDH3 content
D. Acidic phosphatase activity
E. LDH1 and LDH2 content
41. Which antibiotic blocks the active site of an enzyme that many bacteria used to make cell-walls.
(A) Amphotericin
(B) Gentamicin
(C) Penicillin
(D) Cephalosporin

42. The graph shows an enzyme-controlled reaction. The enzyme concentration is kept constant.
At concentrations of substrate greater than X, which of the following statements is true?
A The rate of reaction is limited by enzyme concentration.
B The rate of reaction tends towards zero.
C The substrate has an inhibitory effect.
D The products have an inhibitory effect.
Curve X represents the relationship between an enzyme and the concentration of its substrate under optimal conditions and without an inhibitor.

43. Which one of the curves A, B, C or D represents the result when the same experiment is conducted in the presence of a fixed, low concentration of a reversible, competitive inhibitor?
44. Which one of the curves A, B, C or D represents the result when the same experiment is conducted in the presence of a fixed, low concentration of an irreversible, non-competitive inhibitor?
45. Acetyl-CoA-carboxylase (the key enzyme in fatty acid synthesis) is regulated by feed-back influence of end-product – Palmityl-CoA. Feed-back inhibition is subtype of:
A. Allosteric inhibition
B. Irreversible inhibition
C. Competitive inhibition
D. Covalent modification
E. Uncompetitive inhibition

I. Combine drug and disease where it used
1. Allopurinol
A. Muscle relaxant
2. Asparginase
B. Leukemia
3. Sulfonilamide
C. Gout
4. Succinilcholine
D. Infection disease
5. Neostigmine
E. Myastegnia gravis

II. Which vitamin deficiency cause prolonged administration of izoniazide (used for tuberculosis treatment)

III. A  4 -year-old boy was brought for consultation for hematuria, edema of lower extremities as well as swollen right leg. He was the 12the born in a poor family, where one previous child died from malnutrition and dehydration in the period of infancy.  The child was fed only with cow’s milk and biscuits.
From the period of five months, the boy manifested irritability, sweating, poor appetite and cried when somebody touched him
At admission the baby was afebrile, pale, and malnourished; his hair was dry and cracked. Clinical evaluation showed no organomegaly, no neurological signs, gingival bleeding was there and only one tooth was present.
Laboratory findings were as follows: Red Blood Cell Count 3.5 million/mm3; Hemoglobin (Hb) 7 g/dl; Haemtocrit (Hct) 30%; Serum Iron low
Liver functional tests were in the normal range. Ultrasound of kidney was normal. Doppler of blood vessels of both legs was normal which excluded thrombophlebitis. Swelling of the right leg indicated radiological investigation. Massive subperiosteal hematoma on the right femur, dilatated metaphyses and general osteoporosis had been present on the radiogram.
What is the probable diagnosis for this child?






1. Vitamin E reduces the requirement of
(A) Iron
(B) Zinc
(C) Selenium
(D) Magnesium
2. Vitamin B1 coenzyme (TPP) is involved in
(A) Oxidative decarboxylation
(B) Hydroxylation
(C) Transamination
(D) Carboxylation
3. In the body 1 mg of niacin can be produced from
(A) 60 mg of pyridoxine
(B) 60 mg of tryptophan
(C) 30 mg of tryptophan
(D) 30 mg of pantothenic acid
4. The vitamin required as coenzyme for the action of transaminases is
(A) Niacin
(B) Pantothenic acid
(C) Pyridoxal phosphate
(D) Riboflavin
5. A deficiency of vitamin B12 causes
(A) Beri-Beri
(B) Scurvy
(C) Pernicious anemia
(D) Rickets
6. People consuming polished rice as their staple food are prone to
(A) Beriberi
(B) Pellagra
(C) Both (A) and (B)
(D) None of these
7. A classical uncompetitive inhibitor is a compound that binds
A. reversibly to the enzyme substrate complex yielding an inactive ESI complex
B. irreversibly to the enzyme substrate complex yielding an inactive ESI complex
C. reversibly to the enzyme substrate complex yielding an active ESI complex
D. irreversibly to the enzyme substrate complex yielding an active ESI complex
8. Anti-egg white injury factor is
(A) Pyridoxine
(B) Biotin
(C) Thiamin
(D) Liponic acid
9. Vitamin B12 forms coenzymes known as
(A) Cobamine
(B) Transcobalamine I
(C) Transcobalamine II
(D) Both (B) and (C)
10. The vitamin having the highest daily requirement among the following is
(A) Thiamin
(B) Riboflavin
(C) Pyridoxine
(D) Ascorbic acid
11. A deficiency of folate leads to
(A) Megaloblastic anemia
(B) Aplastic anemia
(C) Pernicious anemia
(D) Hypochromic microcytic anemia
12. Antisterility vitamin is
(A) Vitamin B1
(B) Vitamin B2
(C) Vitamin E
(D) Vitamin K
13. Chose photolabile vitamin:
(A) Thiamine
(B) Riboflavin
(C) Niacin
(D) Cholecalciferol
14. On reception to the doctor the patient with symmetric dermatitis of open sites of skin has come. From patient’s story it is established that he eats, basically, cereals and few meat, milk and eggs. Deficiency of which vitamin is principally detected?
(A) Folic acid
(B) Calciferol
(C) Nicotinic acid
(D) Biotin
(E) Tocopherol
15. The patient complains on general weakness and bleeding from gums. What vitamin lack can cause such state?
(A) Vitamin A
(B) Vitamin E
(C) Vitamin C
(D) Vitamin H
(E) Vitamin D
16. The oculist has found out increase of adaptation time of an eye to the darkness at patient. What vitamin insufficiency can cause such symptoms?
(A) Vitamin C
(B) Vitamin E
(C) Vitamin A
(D) Vitamin K
(E) Vitamin D
17. Which statement out of the following is incorrect about the effect of increasing temperature on enzyme activity-
a) Raising the temperature increases the kinetic energy of molecules
b) A ten degree C rise in temperature will increase the activity of most enzymes by 50 to 100%.
c) Most animal enzymes rapidly become denatured at temperatures above 40oC
d) Storage of enzymes at 5°C or below is generally not suitable.
18. Group I enzymes participate in following reactions-
a) Oxidation-reduction
b) Transamination
c) Phosphorylation
d) All of the above
19. A given substrate may be acted upon by a number of different enzymes, each of which uses the same substrate(s) and produces the same product(s). The individual members of a set of enzymes sharing such characteristics are known as-
a) Group specific enzymes
b) Isoenzymes
c) Substrate specific enzymes
d) Allosteric enzymes
20. A 67- year-old army officer in good health previously presented with sudden pain in the great toe.  Serum uric acid level was high, and a diagnosis of gouty arthritis was made He was advised bed rest, pain killers and Allopurinol. What is the mechanism of action of Allopurinol in lowering serum uric acid levels?
a) Suicidal inhibition
b) Non competitive inhibition
c) Allosteric inhibition
d) Feed back inhibition
21. Chose abasicaminoacid:
A Glutamate
B hydroxyproline
C citrulline
D selenocysteine
22. Lipoic acid was excluded from diet of the experimental animals, and during this process the inhibition of their pyruvate dehydrogenase complex was observed. What is lipoic acid for this enzyme?
(A) Allosteric regulator
(B) Substrate
(C) Inhibitor
(D) Coenzyme
(E) Product
23. Potassium cyanide is a poison death of the body comes instantly. Name of the enzyme in
mitochondria on which cyanic potassium can influence (affect) is:
(A) Cytochrome b5
(B) Flavin-containing enzymes
(C) Cytochrome oxidase
(D) NAD - dependent dehydrogenase
(E) Cytochrome P-450
24. The prolonged use of large doses of aspirin causes suppression of prostaglandins synthesis. Which enzyme has reduced activity?
(A) Cyclooxygenase
(B) Peroxidase
(C) 5-lipoxygenase
(D) Phospholipase-A2
(E) Phosphodiesterase
25. Research of electrophoretic spectrum of albumens of blood serum was carried out to a patient with hepatic failure. What physical and chemical properties of albumins molecules are in the basis of this method?
(A) Presence of charge
(B) Hydrophilic properties
(C) Ability to swell up
(D) Optical activity
26. Sulphanilamide drugs are similar by their structure to paraaminobenzoic acid. What is the base of their pharmacological effect?
(A) activating of lipolysis
(B) binding with DNA
(C) inhibition of glycolysis
(D) infringement of vitamin synthesis
(E) destruction of cellular membrane
27. The megaloblastic anemia is diagnosed at the patient. Specify the substance which insufficiency can cause the development of this illness.
(A) Cholecalciferol
(B) Glycine
(C) Copper
(D) Cyanocobalamine
(E) Magnesium
28. While examining the child, doctor found symmetric cheeks roughness, diarrhea and dysfunction of the nervous system. Lack of what food components caused it?
(A) Threonine, pantothenic acid
(B) Methionine, lipoic acid
(C) Lysine, ascorbic acid
(D) Nicotinic acid, tryptophan
(E) Phenylalanine, pangamic acid
29. Malignant macrocytic anemia – Birmer disease– is a result of vitamin В12 lack. What microelement is a part of this vitamin?
(A) Zinc
(B) Molybdenum
(C) Cobalt
(D) Iron
(E) Magnesium
30. Hypovitaminosis of vitamin C leads to reduction of organic matrix formation and infringement of collagen synthesis because this vitamin participates in processes of:
(A) Proline carboxylation
(B) Proline hydroxylation
(C) Lysine carboxylation
(D) Arginine hydroxylation
(E) Tryptophan hydroxylation.
31. Name the enzyme class, whose structure often contains vitamin PP (its derivatives NAD or NADP):
(A) Oxidoreductases
(B) Hydrolases
(C) Ligases
(D) Isomerases
(E) Lyases
32. An enzyme active site is the location in an enzyme where substrate molecules
A) are generated.
B) become catalysts.
C) undergo change.
D) more than one correct response
E) no correct response
33. At the end of a chemical reaction
A. an enzyme's structure is altered
B. an enzyme is detached from the product, has its original structure, and can catalyze more chemical reactions
C. the enzyme loses its ability to catalyze other chemical reactions
D. the enzyme remains attached to the products
34. Conversion of proline into hydroproline and lysine into hydroxyl-lysine in collagen molecules catalyzed by
(K) Lyases
(L) Oxidoreductase
(M) Isomerases
(N) Hydrolases
(O) Transferases
35. A sick woman of 46 y.o. is suffered from progressive muscular dystrophy (Duchenne dystrophy). Name enzyme whose activity in the blood plasma is diagnostic test to prove this disorder:
A. Creatine phosphokinase
B. Lactate dehydrogenase
C. Pyruvate dehydrogenase
D. Glutamate dehydrogenase
E. Adenylate kinase
36. The young man of 18 y.o. with the damage of parenchyma of the liver has in his blood plasma probable elevated level of this enzyme activity:
A. Alanine aminotransferase
B. LDH1
C. Creatine kinase
D. Acidic phosphatase
E. Alpha-amylase
37. Hemorrhagic stroke is observed in patient. There is increase of kinins level in the blood of patient. Contrical preparation was prescribed for the patient to treat him. Name protease whose activity will be inhibited by this preparation in patient’s blood:
A. Kallikrein
B. Pepsin
C. Trypsin
D. Chymotrypsin
E. Collagenase
38. Pathogenic microorganism contain aggression enzymes, that promote virulence for microorganisms. Find out those one:
(A) . Lyase
(B) . Carbo anhydrase .
(C) Hyaluronidase
(D) Oxidase
(E) Transferase
39. New antibiotics are produced from natural ones due to enzymatic reactions. Name synthetic form of enzymes frequently used in pharmaceutical industry:
A. Immobilized enzyme
B. Natural enzyme
C. Denaturated enzyme
D. Enzyme complex with coenzyme
E. Enzyme complex with activator
40. Find out the enzyme whose activity is determined in the blood plasma of patient with
bone tissue pathology:
A. Pepsin
B. Trypsin
C. Amylase
D. Acidic phosphatase
E. Alkalic phosphatase
41. A substrate S can be degraded by two different isozymes (#1 and #2), both obeying Michaelis-Menten kinetics.  The Km for isozyme #1 is 0.1 mM and the corresponding value for isozyme #2 is 10 mM.  Both isozymes have the same Vmax.  If [S] = 5 mM, which of the following statements is correct?
A) Isozyme #1 will degrade S faster than isozyme #2.
B) Isozyme #2 will degrade S faster than isozyme #1.
C) Isozyme #1 will degrade S at a rate equal to half of its maximal velocity.
D) Isozyme #2 will degrade S at a rate equal to half of its maximal velocity.
E) Isozyme #2 will degrade S at its maximal velocity.
42.  Penicillinase is an enzyme present in some bacteria that can inactivate the antibiotic penicillin. Based on the Lineweaver Burk plot below, determine the Vmax and Km of penicillinase.

43. Proserin (neostigmine) was used for the treatment of myasthenia and other disorders of muscular tissue. This preparation is competitive inhibitor of enzyme:
A. Lactate dehydrogenase
B. Citrate synthase
C. Succinate dehydrogenase
D. Arginase
E. Acetylcholine esterase
44. Phosphor-containing organic compounds (mainly, they are poisons to cause CNS paralysis) inhibit acetyl choline transferase across blockage of OH-groups of serine residues in active sites of enzymes. Name type of inhibition for these compounds:
A. Irreversible
B. Reversible
C. Competitive
D. Non-competitive
E. Feed-back inhibition
45. Some insecticides are poisons for humans because they block irreversibly the activity of very important enzyme in nervous tissue. It is:
A. Cytochrome C oxidase
B. ATP synthase
C. Acetylcholine esterase
D. Pyruvate kinase
E. Lactate dehydrogenase

I. Match drug and enzyme which inhibited by this drug
1. Methotrexate
A. Cytochrome oxidase
2. Allopurinol
B. Acetylcholine esterase

3. Cyanide
C. Dihydrofolate reductase

4. Amphetamine
D. Xanthine oxidase

5. Diisopropyl fluorophosphates
E. MAO

II. A homeless person has been brought to emergency. Blood biochemistry reveals high lactate levels. An impaired activity of PDH complex is suspected. Which vitamins deficiency can cause such symptoms?

III. Man suffers from short breathing. He smokes 1 pack cigarettes a day. Genetic screening revealed that his has variety of AT-SS. What his diagnose and what medicine should be prescribed?









1. The pellagra preventive factor is
(A) Riboflavin
(B) Pantothenic acid
(C) Niacin
(D) Pyridoxine
2. The enzymes with which nicotinamide act as coenzyme are
(A) Dehydrogenases
(B) Transaminases
(C) Decarboxylases
(D) Carboxylases
3. The coenzyme required for conversion of pyruvate to oxaloacetate is
(A) FAD
(B) NAD
(C) TPP
(D) Biotin
4. Sulpha drugs interfere with bacterial synthesis of
(A) Lipoate
(C) Tetrahydrofolate
(B) Vitamin E
(D) Ascorbic acid
5. Niacin can be synthesized in human beings from
(A) Histidine
(B) Phenylalanine
(C) Tyrosine
 (D)Tryptophan
6. When eggs are cooked
(A) Biotin is destroyed but avidin remains unaffected
(B) Avidin is inactivated but biotin remains unaffected
(C) Both avidin and biotin are inactivated
(D) Both avidin and biotin remain unaffected
7. Methylcobalamin is required for formation of
(A) Serine from glycine
(B) Glycine from serine
(C) Methionine from homocysteine
(D) All of these
8. This vitamin acts as antioxidant.
(A) Vitamin A
(B) Vitamin D
(C) Vitamin E
(D) Vitamin K
9. Biotin is essential for
(A) Translation
(B) Carboxylation
(C) Hydroxylation
(D) Transamination
10. Carrot, pumpkin and other red vegetables contain carotin. Deficiency of what vitamin is supplied with these vegetative pigments?
(A) Tocopherol
(B) Naftohinon
(C) Riboflavin
(D) Retinol
(E) Calciferol
11. During child (age of 11 months) examination by pediatrist, bended bones of the low limbs and low bones mineralization of skull were found. What vitamin lack leads to the pathology?
(A) Thiamin
(B) Cholecalciferol
(C) Pantothenic acid
(D) Bioflavonoid
(E) Riboflavin
12. The patient complained on the general weakness and bleeding from gums. What vitamin insufficiency can it be at patient?
(A) Vitamin В1
(B) Vitamin E
(C) Vitamin РР
(D) Vitamin D
(E) Vitamin C
13. 42-year-old obese female presented to the emergency center with complaints of worsening nausea, vomiting, and abdominal pain. Her pain was in the mid epigastric area and right upper quadrant. Blood biochemistry revealed high serum amylase level. What is the probable diagnosis for this patient?
a) Viral hepatitis
b) Acute Pancreatitis
c) Renal colic
d) Acute gastritis
14. The drug Fluorouracil is recommended for the treatment of cancers. It undergoes a series of changes and then binds to Thymidylate synthase enzyme resulting in its inhibition and blockage of cell division. This mode of inhibition is most probably due to-
a) Allosteric inhibition
b) Competitive inhibition
c) Noncompetitive Inhibition
d) Suicidal inhibition                   
15. Which statement out of the followings is incorrect about the effect of increasing temperature on enzyme activity-
a) Raising the temperature increases the kinetic energy of molecules
b) A ten degree C rise in temperature will increase the activity of most enzymes by 50 to 100%.
c) Most animal enzymes rapidly become denatured at temperatures above 40oC
d) Storage of enzymes at 5°C or below is generally not suitable.
16. The degree of inhibition α by a competitive inhibitor is obtained from
(A) measurement of Vmax.
(B) measurement of the y-intercept on a Limeweaver-Burke Plot.
(C) measurement of Km.
(D) crystallographic studies.
(E) is unrelated to the binding affinity of the inhibitor to the enzyme.
17. During the pathological processes, accompanied by hypoxia, incomplete
reduction of oxygen molecules in respiratory chain and the accumulation of hydrogen peroxide is take place. Specify the enzyme, which catalyze its destruction.
(A) Aconitase
(B) Cytochrome oxidase
(C) Peroxidase
(D) Ketoglutarate dehydrogenase
(E) Catalase
18. Prolonged use of large doses of aspirin causes the inhibition of synthesis of prostaglandins by reducing the activity of the enzyme:
(A) Peroxidase
(B) Cyclooxygenase
(C) 5- lipoxygenase
(D) Phospholipase A-2
(E) Phosphodiesterase
19. Different functional groups can be presented in the structure of L-amino acid’s radicals. Identify the group that can form ester bond:
(A) –OH
(B) -CONH2
(C) -SH
(D) -NH2
(E) -CH3
20. Which of the following statements about uric acid is correct?
a) Uric acid is readily soluble in the blood.
b) Overproduction of PRPP leads to the formation of excess uric acid.
c) Uric acid is the oxidized product of purines and pyrimidines
d) Allopurinol is a suicide inhibitor of PRPP aminotransferase.
21. Dermatitis has appeared at patient after eating raw (unboiled) eggs. What avitaminosis has emerged?
(A) Avitaminosis of folic acid
(B) Avitaminosis of biotin
(C) Avitaminosis of tocoferol
(D) Avitaminosis of thiamin
22. The gerontology institute advises to old people to use a complex of vitamins which contains vitamin E. What main function does it carry out?
(A) Antiscorbutic function
(B) Antihemorrhagic function
(C) Antioxidant function
(D) Antineuritic function
(E) Antidermatitic function
23. For diagnostics of some diseases, aminotransferase activity is researched in blood. What vitamin is a coenzyme of these enzymes?
(A) b6
(B) В2
(C) b1
(D) В9
(E) В5
24. Concentration of pyruvate is increased in the patient's blood, the most of which is excreted with urine. What avitaminosis is observed in the patient?
(A) Avitaminosis b1
(B) Avitaminosis E
(C) Avitaminosis В3
(D) Avitaminosis B6
(E) Avitaminosis В2
25. Sample questions The protein portion of a conjugated enzyme is called a(n)
 A) apoenzyme.
B) coenzyme.
 C) holoenzyme.
 D) cofactor.
26. Which of the following could be a component of a conjugated enzyme?
A) coenzyme
B) cofactor
C) apoenzyme
D) more than one correct answer
E) no correct response
27. The location on an enzyme where binding occurs is known as the
A. action point
 B. enzyme
C. binding location
D. active site
28.Which of the following kinetic parameters best describes how well suited a specific compound functions as a substrate for the enzyme?
 (a) Km
(b) Vmax
(c) kcat
(d) kcat/Km
29. AST and ALT used diagnosis. What vitamin is important for these enzymes activity?
(A) vitamin pp
(B) folic acid
(C) riboflavin
(D) niacin
(E) thiamin
30. Affine chromatography method with use of special ligand placed on the carrier proposed to obtain from pancreas of animals’ enzyme amylase preparation. Name substances that may be used as the ligand:
(A) Glucose
(B) Starch
(C) Sucrose
(D) Cellulose
(E) Lactose
31. Enzyme catalyzes the transfer of structural fragment from one substrate to other one to form two products. Name the class of this enzyme.
(A) Hydrolase
(B) Isomerase
(C) Transferase
(D) Oxidoreductase
(E) Ligase
32. The most likely effect of a non-competitive inhibitor on an Michaelis-Menten enzyme is to
A. Increase the Vmax
B. Decrease the Vmax
C. Increase both the Vmax and the Km
D. Decrease both the Vmax and the Km
33. The human species can biosynthesize
(A) Vitamin C
(B) Vitamin B12
(C) Thiamine
(D) Niacin
34. Digestive enzymes are
(P) Lyases
(Q) Oxidoreductase
(R) Isomerases
(S) Hydrolases
(T) Transferases
35. The increase of activities for enzymes LDH1, LDH2, AsAT, creatine phosphate kinase was checked in the blood serum of diseased person. Name the probable organ (tissue) where pathology was developed:
A. Heart muscle (beginning of myocardium infarction)
B. Skeletal muscle (dystrophy or atrophy)
C. Kidney and adrenal gland
D. Connective tissue
E. Liver and kidney
36. There was revealed acute increase of AsAT activity in the blood serum of patient for whom in 12 hours before acute attack of chest pain was checked. Find out the pathology whose development is associated with those change in the blood:
A. Myocardium infarction
B. Viral hepatitis
C. Collagenosis
D. Diabetes mellitus
E. Diabetes insipidus
37. Sick man 49 years old (a driver by profession) complains of unbearable retrosternal pain that was found in the cervical 2 hours ago. It is severe state, the patient has pale face, and, and his heart sounds are weakened. The laboratory investigation revealed high activity of Creatine phosphate kinase and LDH1. Name the disease which may by observed in patient:
A. Acute myocardium infarction
B. Acute pancreatitis
C. Stenocardia
D. Cholestasis
E. Diabetes mellitus
38. Fibrinolytic drugs can dissolve formed in human’s blood thrombus. Choose those preparation:
(A) . Riboflavin
(B) Streptokinase .
(C) Isoniazide
(D) Phenobarbital
(E) Vicasol
39. Increased total activity of LDH is found in the blood plasma of patient. It may be at disorders associated with diseases of heart, kidney and liver. Name additional clinical test to make differentiation in diagnosis of this patient:
A. LDH isozymes content determination in blood plasma
B. Glucose content determination in the blood
C. Ketone bodies determination in the blood plasma
D. Total cholesterol determination in blood plasma
E. Amylase activity determination in blood plasma
40. The best test for acute pancreatitis in the presence of mumps is
(A) A serological test for mumps
(B) Serum amylase
(C) Urinary amylase
(D) Serum lipase
41. In the graphs shown below, in which the initial rate of an enzyme-catalyzed reaction was plotted against the substrate concentration, the solid line represents data obtained in the absence of any drug while the dotted line represents data obtained in the presence of the drug X. Which of the following statements about this system is TRUE?

A) Drug X increases the maximal velocity of the enzyme.
B) Drug X acts as a positive effector of the enzyme.
C) Drug X acts as a negative effector of the enzyme.
D) Drug X has no effect on the enzyme.
E) The enzyme exhibits simple Michaelis-Menten kinetics in the absence of Drug X.
42. Zn+2 is an inorganic activator for enzyme.
(A) Carbonic anhydrase
(B) Phosophatase
(C) Chymotrypsin
(D) Maltase
43. Proserin preparation is reversible inhibitor of acetylcholine esterase. Find out mechanism of proserin (P) action as inhibitor:
A. Competition of P with acetylcholine to attach active site of enzyme
B. Enzyme denaturation by P
C. Covalent modification of active site of enzyme by P
D. Fe oxidation in active site of enzyme by P
E. Covalent modification of allosteric site of enzyme by P
44. Treatment of methanol poisoning of a patient is the use of ethanol as preparation (per os or intravenously) in a quantity that can cause for healthy person toxicification. Find out explanation for effective ethanol use as drug in this case:
A. The affinity of ethanol to active site of alcohol dehydrogenase is much higher than for methanol
B. Ethanol is allosteric inhibitor of alcohol dehydrogenase
C. Ethanol blocks the coenzyme of alcohol dehydrogenase
D. Ethanol is destroyed to form more toxic compounds as methanol
E. Ethanol suppresses diffusion of methanol
45. The use of colors with high content of lead is limited in production of toys for kids. Lead ions toxicity is explained from their influence as inhibitors for enzymes. Name type of inhibition for lead ions:
A. Non-competitive
B. Competitive
C. Uncompetitive
D. Allosteric
E. Irreversible

I. Connect enzyme and its tissue location
1. LDH 1
A. Brain
2. LDH 5
B. Panreas cancer
3. BB-CPK
C. Heart
4. Nagao Al Phosphatase
D. Prostatic cancer
5. Acid Phosphatase
E. Liver

II. A 32- year- old male reported to emergency with active bleeding from nose.  History revealed that he had been on Orlistat for weight reduction from the past two years. He had started Orlistat without the advice of any practitioner and  had lost nearly 20 kg of body weight .There was no history of hypertension, bleeding disorder or any other medical illness. No such bleeding episode occurred in the past.
There was no abnormality detected upon local examination of nose.  What is the relationship between Orlistat and epistaxis?

III. Why is it said that babies undergoing phototherapy for physiological jaundice are prone to develop riboflavin deficiency?