Biological chemistry (collection of test tasks)

(1)

MINISTRY OF PUBLIC HEALTH OF UKRAINE

HIGHER STATE EDUCATIONAL ESTABLISHMENT OF UKRAINE

«UKRAINIAN MEDICAL STOMATOLOGICAL ACADEMY»

BIOLOGICAL CHEMISTRY.

СOLLECTION OF TEST TASKS

Textbook

Poltava – 2018

(2)

МІНІСТЕРСТВО ОХОРОНИ ЗДОРОВ’Я УКРАЇНИ ВИЩИЙ ДЕРЖАВНИЙ НАВЧАЛЬНИЙ ЗАКЛАД УКРАЇНИ

«УКРАЇНСЬКА МЕДИЧНА СТОМАТОЛОГІЧНА АКАДЕМІЯ »

ГОРДІЄНКО Л.П., БІЛЕЦЬ М.В., НЕПОРАДА К.С.

HORDIIENKO L.P., BILETS M.V., NEPORADA K.S.

BIOLOGICAL CHEMISTRY.

COLLECTION OF TEST TASKS

Біологічна хімія .

Збірник тестових завдань

Навчальний посібник Textbook

Полтава – 2018

Poltava – 2018

(3)

UDC 577.1:378.14

It is recommended by the Academic Council of the Higher State Educational Establishment of Ukraine «Ukrainian Medical Stomatological Academy» as a textbook for English-speaking students of higher education institutions of the Ministry of Public Health of Ukraine (report № 3, 22.11.2017 y).

Authors: Ph.D. Medicine, Associate professor L.P. Hordiienko; Ph.D. Biology, Associate professor M.V. Bilets; Doctor of Medical Science, Professor K.S. Neporada

Textbook «Biological chemistry. Collection of test tasks» for English-speaking students of higher medical educational institutions of the Ministry of Public Health of Ukraine. – Poltava, 2018. – 148 p. In English language.

Textbook «Biological chemistry. Collection of test tasks» for English-speaking students of higher educational institutions of the Ministry of Public Health of Ukraine was prepared in accordance with the program "Biological and bioorganic chemistry", compiled by the staff of the supporting department of bioorganic and biological chemistry of the O.O.

Bogomolets National Medical University. Test tasks are structured around the topics of practical training, which corresponds to the standards of training according to the principles of the credit-module system and contributes to improving the quality of student training.

Reviewers:

Zaichko N.V., Doctor of Medical Science, Professor, Head of Department of Biological and General Chemistry of VN Pirogov MMU;

Nakonechna O.A., Doctor of Medical Science, Professor, Head of Department of Biological Chemistry of Kharkiv National Medical University;

Bieliaieva O.M., PhD in Pedagogy, Associate Professor, Head of Department of Foreign Languages with Latin Language and Terminology of Higher State Educational Establishment of Ukraine «Ukrainian Medical Stomatological Academy».

(4)

УДК 577.1:378.14

Рекомендовано вченою радою Вищого державного навчального закладу України «Українська медична стоматологічна академія» як навчальний посібник для англомовних студентів вищих навчальних закладів МОЗ України (протокол № 3 від 22.11.2017 року).

Автори: к.мед.н., доцентЛ.П. Гордієнко, к.біол.н., доцент М.В. Білець, д.мед.н., професор К.С. Непорада

Навчальний посібник «Біологічна хімія. Збірник тестових завдань» для англомовних студентів вищих навчальних закладів МОЗ України. – Полтава, 2018. – 148 с. Англійськоюмовою.

Навчальний посібник «Біологічна хімія. Збірник тестових завдань» для англомовних студентів вищих навчальних закладів МОЗ України підготовлено у відповідності з програмою «Біологічна та біоорганічна хімія», яка складена співробітниками опорної кафедри біоорганічної та біологічної хімії Національного медичного університету імені О.О. Богомольця. Тестові завдання структуровані за темами практичних занять, що відповідає стандартам навчання, згідно засад кредитно-модульної системи та сприяє підвищенню якості підготовки студентів.

Рецензенти:

Заічко Н.В. – доктор медичних наук, профессор, завідувачкафедри біологічної та загальної хімії Вінницького національного медичного університету імені М.І. Пирогова;

Наконечна О.А. – доктор медичних наук, профессор, завідувач кафедри біологічноїхіміїХарківського національногомедичногоуніверситету;

Бєляєва О.М. – кандидат педагогічних наук, доцент, завідувач кафедри іноземних мов з латинською мовою та медичною термінологією Вищого державного навчального закладу України «Українська медична стоматологічна академія».

(5)

Module ІІ

1. Control of initial level of knowledge. The subject and tasks of biochemistry. The aim and methods of biochemical research, its clinical and diagnostic value.

1. What qualitative reaction is used to determine the residues of α-amino acids in the protein structure and the free α-amino acids?

A. Ninhydrin test B. Xanthoproteic test C. Lead-sulfide test D. Sakaguchi test E. Ehrlich test

2. In hydrolysis of proteins and peptides 20 different α-L-amino acids are released that are called proteinogenic amino acids.

Furthermore, in humans there are also some other amino acids which are not part of the proteins, select them:

A. Alanine B. Ornithine C. Cysteine D. Methionine E. Serine

3. Protein molecules are biopolymers that enforce a number of important functions. The enzymatic function of proteins is:

A. Catalysis of biochemical reactions B. Release of free chemical energy C. Protection against infection

D. Formation of biological membranes E. Transport of oxygen

4. Proteins have several levels of structural organization. Hemoglobin is a complex protein which serves as an oxygen- transporting protein and has:

A. Fibrillar structure B. α-structure

C. Quaternary structure

D. Structure similar to collagen E. Primary structure

5. Which class of proteins by the chemical structure hemoglobin belongs to?

A. Chromoproteins B. Metalloproteins C. Phosphoproteins

D. Glycoproteins E. Lipoproteins

6. Bioorganic high-molecular compounds that consist of residues of α-L-amino acids and connected by amide (peptide) bonds are called:

A. Nucleic acids B. Carbohydrates C. Lipids

D. Proteins

E. Heterocyclic compounds

7. What bioorganic compounds are aldehyde and ketone derivatives of polyhydric alcohols?

A. Carbohydrates B. Proteins

C. Heterocyclic compounds D. Lipids

E. Nucleic acids

8. What class of bioorganic compounds has a distinctive feature of being soluble in the nonpolar solvents but insoluble in water and other polar solvents?

A. Heterocyclic compounds B. Carbohydrates

C. Proteins D. Nucleic acids E. Lipids

9. What are polymers of mononucleotides?

A. Nucleic acids B. Proteins C. Carbohydrates D. Lipids

E. Heterocyclic compounds

10. The cyclic compounds which in addition to carbon contain in the ring at least one atom of another element (heteroatom) are called:

A. Proteins

B. Heterocyclic compounds C. Carbohydrates

D. Lipids

E. Nucleic acids

11. What are the products of hydrolysis of trioleylglycerol?

A. Glycerol and three oleic acids B. Glycerol and three palmitic acids

(9)

C. Water and carboxylic acid D. Glycerol and water E. Glycerol and base

12. Transfer RNAs play an important role in the biosynthesis of protein molecules on ribosomes. The tertiary structure of tRNA is:

A. Globular B. Letter S C. Cloverleaf D. Fibrillar E. Helix

13. Which homopolysaccharide is the molecular form of glucose storage in the human body?

A. Glycogen B. Cellulose C. Amylose D. Starch E. Dextran

14. Lipoproteins are particles that consist of noncovalently associated lipids and proteins.

What is the main function of lipoproteins in the blood plasma?

A. Regulatory B. Plastic C. Energy D. Transport E. Catalytic

15. Fatty acids are used for the synthesis of many biologically important compounds in human body. Some of them are not synthesized because mammals do not possess the enzymes for their biosynthesis. Which of the following fatty acids is an essential fatty acid?

Α. α-Linoleic acid B. Palmitic acid C. Oleic acid D. Stearic E. Butyric

16. A nucleotide is composed of:

A. Nitrogenous base and phosphate

B. Hexose, nitrogenous base and phosphate C. Nitrogenous base and pentose

D. Hexose and phosphate

E. Nitrogenous base, pentose and phosphate

17. What is the biological function of messenger RNA (mRNA)?

A. mRNA is a matrix for biosynthesis of proteins

B. mRNA transports amino acids C. mRNA hydrolyzes proteins

D. mRNA catalyzes peptide bonds formation E. mRNA activates rRNA

18. A nucleoside is composed of:

A. Nitrogenous base and pentose

B. Hexose, nitrogenous base and phosphate C. Nitrogenous base, pentose and phosphate D. Hexose and phosphate

E. Nitrogenous base and phosphate

19. What branch of biochemistry studies a chemical composition of living organisms and a structure of bioorganic molecules, which are a part of living matter?

A. Dynamic biochemistry B. Static biochemistry C. Functional biochemistry D. Medical biochemistry E. Enzymology

20. What branch of biochemistry studies transformation of substances that form in its entirety metabolism of living organisms?

21. What branch of biochemistry studies the biochemical reactions in various organs and tissues underlying the physiological functions?

22. What branch of biochemistry studies metabolic patterns in normal and pathological conditions (pathochemistry) in the human body?

A. Clinical biochemistry B. Static biochemistry C. Dynamic biochemistry D. Functional biochemistry

(10)

E. Enzymology

23. Choose amino acids that are in a fraction of basic amino acids and have positively charged radicals according to the results of chromatography:

A. Alanine, proline, tyrosine B. Aspartate, Glutamate

C. Leucine, isoleucine, methionine D. Lysine, arginine, histidine E. Tryptophan, cysteine, glycine

24. Choose amino acids that are in a fraction of acidic amino acids and have negatively charged radicals according to the results of chromatography:

A. Aspartate, Glutamate B. Lysine, arginine, histidine C. Leucine, isoleucine, methionine D. Alanine, proline, tyrosine E. Tryptophan, cysteine, glycine

2. Analysis of structure, physical and chemical properties of protein enzymes.

1. Five isoforms of lactate dehydrogenase were identified in human serum. Which property proves that marked isoenzyme forms are of the same enzyme?

A. Catalyze the same reaction B. The same molecular weight C. Tissue localization

D. The same physical and chemical properties E. The same electrophoretic mobility

2. Which enzymes catalyze the conversion of proline to hydroxyproline and lysine to hydroxylysine in the collagen molecule?

A. Hydroxylases B. Hydrolases C. Dehydrogenases D. Oxidases

E. Dehydratases

3. The enzyme oxidase of D-amino acids only catalyzes a deamination of D-amino acids.

Which property of enzymes is shown in this case?

A. Stereochemical specificity B. Thermolability

C. Relative specificity D. Dependence on pH

E. Absolute specificity

4. Azaserine is a structural analogue of glutamine. It is inhibitor of purine nucleotide biosynthesis. Which type of inhibition is characteristic of this drug?

A. Irreversible B. Competitive C. Noncompetitive D. Incompetitive E. Allosteric

5. Metabolic acidosis was developed in the patient. An activity of enzymes was decreased, because of:

A. A charge of enzymes was changed

B. Activity of mitochondrial enzymes was inhibited and an increased activity of lysosomal enzymes led to the activation of metabolic processes

C. An activity of intracellular enzymes didn’t change significantly

D. There was a total inhibition of tissue enzymes

E. There was a total activation of tissue enzymes

6. Specify an enzyme with optimal pH = 2.0:

A. Pepsin B. Trypsin C. Chymotrypsin D. α-Amylase E. Collagenase

7. The relative specificity of enzymes is only an ability to catalyze a conversion of:

A. One metabolic process B. Specific stereoisomers

C. A group of substrates that have the same chemical structure

D. One substrate E. Two substrates

8. The absolute specificity of enzymes is only an ability to catalyze a conversion of:

A. One substrate

B. One of stereoisomers

C. One specific type of a chemical bond D. One specific group of substrates E. Many substrates

9. Specify an enzyme with optimal pH = 11.0:

A. Arginase

(11)

B. Catalase C. Lipase

D. Pyruvate dehydrogenase E. Collagenase

10. A lot of enzymes consist of several subunits (protomers) that are joined by non- covalent bonds. What are they called?

A. Oligomeric enzymes B. Coenzymes

C. Apoenzymes

D. Multienzyme complexes E. Isoenzymes

11. What is a region of an enzyme where substrate molecules bind and undego a chemical reaction called?

A. Activator B. Allosteric Site C. Inhibitor D. Holoenzyme E. Active site

12. What is a membrane-bound multienzyme complex?

A. Specific enzymes are bound with the lipid bilayer of subcellular organelles

B. Specific enzymes are bound together by hydrogen bonds

C. Specific enzymes are not themselves bound

D. An enzyme is consisted of several protomers

E. Certain enzymes are bound together by covalent bonds

13. What is a non-protein part of enzyme called?

A. Coenzyme B. Apoenzyme C. Activator D. Holoenzyme E. Inhibitor

14. What is a protein part of the enzyme called?

A. Inhibitor B. Coenzyme C. Activator D. Apoenzyme E. Holoenzyme

15. What is a non-protein part of enzyme covalently binding with the protein part called?

A. Coenzyme B. Prosthetic group C. Activator

D. Inhibitor E. Holoenzyme

16. Enzymes speed up chemical reactions due to:

A. Reduction of activation energy B. Increasing of activation energy

C. Transition of molecules in an active state D. The formation of additional bonds E. The formation of covalent bonds

17. How does the increasing of enzyme concentration effect enzyme reaction rate?

A. It proportionally increases B. It proportionally reduces C. It doesn’t change

D. It increases and then remains constant E. It decreases and then remains constant 18. What are substrates of proteolytic enzymes?

A. Proteins B. Carbohydrates C. Vitamins D. Lipids E. Nucleic acids 19. What are enzymes?

A. Structural components of biological membranes

B. Biocatalysts of protein nature C. Inorganic catalysts

D. Microelements that increase a rate of chemical reactions

E. Organic molecules of a non-protein nature 20. What is a chemical nature of enzymes?

A. Lipid B. Protein

C. Polysaccharide D. Nucleic acid E. Vitamin

21. What are common properties between enzymes and inorganic catalysts?

A. Specificity of action

B. Their activity is dependent upon pH

(12)

C. They catalyse thermodynamically possible reactions only

D. Dependence on an amount of substrate E. Dependence on an effector’s action 22. What properties do enzymes have?

A. Thermolability

B. The small molecular weight C. Luminescence

D. Resistance to the effects of heavy metal salts

E. Thermostability

23. What are functions of enzymes connected with?

A. Increasing of chemical reactions B. Decreasing of chemical reactions

C. Decrease in the pH optimum of the chemical reactions

D. Decrease in the temperature optimum of chemical reactions

E. Neutralization of products of chemical reactions

24. What is a role of an active site of an enzyme?

A. Binding and conversion of substrate B. Attaching of enzymes to the membrane C. Regulation of enzyme’s activity

D. Interaction between enzymes E. Binding of allosteric effectors

25. What happens with enzymes by the action of a high temperature?

A. Violation of a primary structure B. Hydrolysis

C. Formation of an enzyme-substrate complex D. Blocking of an active site

E. Denaturation

26. What determines a solubility of an enzyme?

A. Molar mass of the solvent

B. The ratio of hydrophobic and hydrophilic amino acid radicals in the structure of an enzyme

C. Concentration of a solvent

D. Atomic composition of a solvent E. The presence of a proper catalyst

27. What determines electrochemical properties of enzymes?

A. Qualitative and quantitative composition of amino acids

B. Presence of a peptide bond C. Denaturation

D. Renaturation

E. Presence of protomers of protein molecules 28. At what temperature does an inactivation of enzymes begin as a result of their denaturation?

A. 50-60⁰С B. 39⁰С C. 80⁰С D. 100⁰С E. 40 ⁰С

3. Measurement of enzymic activity. Units of catalytic activity of enzymes. Analysis of enzymic processes by the reaction type of main classes of enzymes.

1. The enzyme catalyzes the transfer of a functional group from one substrate to another one. Specify a class of the enzyme:

A. Hydrolases B. Transferases C. Isomerases D. Oxidoreductases E. Ligases

2. Biogenic amines are produced by decarboxylases. What a class of enzymes decarboxylases belong to?

A. Isomerases B. Lyases

C. Oxidoreductases D. Hydrolases E. Transferases

3. Glucokinase catalyzes a reaction of a transfer of a phosphate group from ATP to glucose. What a class of enzymes glucokinase belongs to?

A. Transferases B. Oxidoreductases C. Isomerases D. Hydrolases E. Lyases

4. Biological oxidation is a main energy molecular process. Which class of enzymes catalyzes this process?

(13)

A. Oxidoreductases B. Hydrolases C. Lyases D. Ligases E. Transferases

5. Reactive oxygen species, including superoxide radical, are produced in the human body. Which enzyme is necessary for the inactivation of superoxide radical?

A. Superoxide dismutase B. Catalase

C. Glutathione D. Peroxidase

E. Glutathione peroxidase

6. What class of the enzymes aerobic dehydrogenases belongs to?

A. Oxidoreductases B. Lyases

C. Transferases D. Hydrolases E. Ligases

7. What class of the enzymes protein kinases belongs to?

8. What class of the enzymes pepsin belongs to?

C. Hydrolases D. Transferases E. Ligases

9. The activators of the enzymes are substances that:

A. Increase the rate of a reaction B. Decrease the rate of a reaction

C. Stimulate a denaturation of the enzymes D. Increase a reversibility of a reaction E. Cause enzymes’ destruction

10. What are enzymes catalyzing reactions of an intramolecular transfer of groups or atoms called?

A. Isomerases B. Ligases

C. Hydrolases D. Transferases E. Oxidoreductases

11. What are enzymes catalyzing the splitting of the intramolecular bonds of organic substances by the use of water called?

A. Hydrolases B. Ligases C. Lyases

D. Oxidoreductases E. Transferases

12. The enzyme inhibitors are substances that:

A. Decrease the rate of the reaction B. Increase the rate of the reaction C. Stimulate enzymes’ denaturation

D. Increase the reversibility of the reaction E. Cause enzymes’ destruction

13. According to the type of a chemical reaction all enzymes are divided into:

A. Seven classes B. Nine classes C. Five classes D. Seven subclasses E. Six classes

14. An international unit for an enzyme activity is katal, defined as an amount of enzyme that transforms:

A. 1 mol of the substrate per 1 second B. 1 gram of the substrate per 1 second C. 1 gram of the substrate per 1 hour D. 1 mol of the product per 1 hour E. 1 μmol of the substrate per 1 second 15. Monooxygenases belong to the class of:

16. What principle is used to classify all enzymes into six classes?

A. The type of the chemical reaction B. The type of bonds

C. The type of the substrate

D. Mechanism of an enzyme action E. The type of the product

(14)

17. What nomenclature is used to give a name to the enzymes in our days?

A. Systematic B. Usual C. Common D. United E. The main

18. The enzymes of the cytochrome system participate in:

A. Transfer of hydrogen atoms B. Transfer of electrons

C. Transfer of oxygen atoms D. Transfer of proteins E. Transfer of molecules

19. How many numbers are in the enzyme code by the systematic nomenclature?

A. Six B. Four C. Three B. Five E. Seven

20. Enzymes are placed in the cell in such way to ensure the performance of the functions of certain organelles. Which of the following enzymes are the lysosomal ones?

A. Enzymes for the synthesis of urea B. Enzymes of protein synthesis C. Hydrolytic enzymes

D. Fatty acid synthesis enzymes E. Glycogen synthesis enzymes

21. Peptidases catalyze the splitting of:

A. Polypeptides B. Nucleic acids C. Polysaccharides D. Lipids

E. Oligosaccharides

22. What enzyme belongs to peptidases?

A. Urease B. ATP-ase

C. RNA-polymerase D. Amylase

E. Trypsin

23. The iron deficiency was established by a laboratory investigation. What enzyme activity is decreased in this case?

A. Catalase

B. Carbonic anhydrase

C. Ceruloplasmin D. Carboxypeptidase E. Glutathione peroxidase

24. Pharmacological preparations which contain mercury, arsenic and other heavy metals inhibit enzymes which have a sulfhydryl group. What amino acids are used for the reactivation of these enzymes?

A. Cysteine B. Isoleucine C. Histidine D. Aspartic acid E. Glycine

25. After applying the extract from pancreas into a tube with a solution of starch, it was observed a decline of blue staining in the sample with a solution of iodine, which indicates to hydrolysis of starch. Under the influence of what pancreatic enzyme it happens?

A. α-Amylase B. Chymotrypsin C. Lipases D. Aldolases E. Trypsin

26. Specify the class of enzymes that uses ATP energy for the synthesis of new bonds:

A. Isomerases B. Oxidoreductases C. Hydrolases D. Ligases E. Transferases

4. Analysis of the mechanism of enzymic action and kinetics of enzymic catalysis.

1. Saliva contains an enzyme that catalyses the hydrolysis of α-1,4-glycosidic bonds of starch. What is the enzyme called?

A. Peptidase B. Lactase C. Nuclease D. Lysozyme E. Amylase

2. It was revealed a significant decrease in pepsin activity in the analysis of the gastric juice of a patient with hypoacid gastritis.

Indicate the possible biochemical mechanism

(15)

of this phenomenon:

A. The absence of the intrinsic factor in the gastric juice

B. Denaturation of the enzyme molecule C. Competitive inhibition of the enzyme D. Decrease in the activation energy of the enzymatic reaction

E. Disruption of an enzyme formation from a proenzyme

3. An unknown substance was added to the enzyme-substrate system during studying the properties of an enzyme. As a result, the Michaelis constant was increased by 2 times.

What phenomenon was observed?

A. Competitive inhibition B. Allosteric activation C. uncompetitive inhibition D. Noncompetitive inhibition E. Irreversible inhibition

4. Proteolytic enzymes of stomach and pancreas are synthesized in an inactive form - as zymogens, and then activated in the digestive tract. What is a proteolytic enzyme of stomach synthesized in an inactive form called?

A. Pepsin B. Trypsin C. Chymotrypsin D. Elastase E. Collagenase

5. Sulfonamide preparations inhibit the growth of bacteria. They are used for the treatment of the infectious diseases. What is the mechanism of their action?

A. Competitively inhibit the synthesis of folic acid

B. Allosteric inhibition of bacterial enzymes C. Participate in oxidation-reduction processes

D. Inhibit the absorption of folic acid

E. Irreversibly inhibit the synthesis of folic acid necessary for the normal functioning of bacteria

6. The composition of saliva includes enzymes that break down carbohydrates.

Specify saliva enzyme involved in hydrolysis of starch:

A. Amylase B. Lactase

C. Nuclease D. Maltose E. Peptidase

7. Sulfanilamide preparations were prescribed to thepatients with angina. The antimicrobial effect of sulfanilamides is caused by the violation of the synthesis of folic acid. With what substance do sulfanilamides compete for the active site of the enzyme?

A. Para-aminobenzoic acid B. Glutamic acid

C. Citrate D. Succinate E. Malate

8. Vomiting, flatulence and diarrhea were appeared in a newborn baby during the breast- feeding. The hereditary insufficiency of what enzyme is a cause of this state?

A. Lactase B. Maltase C. Isomerase

D. Oligo-1,6-glucosidase E. Pepsin

9. Biological oxidation and neutralization of xenobiotics is due to the heme-containing enzymes. Which metal is an obligatory component of these enzymes?

A. Fe B. Zn C. Co D. Mg E. Mn

10. The buffer solution and an enzyme were incubated at 80⁰С for 30 minutes under modeling the biochemical process. The qualitative reaction is negative to the reaction product. What property of enzymes has led to the stop of the chemical reaction?

A. Absolute specificity B. Denaturation of enzymes C. Stereospecificity

D. Dependence on pH E. Relative specificity

11. A patient has a reduced gastric acidity and the violated digestion of proteins in the stomach. What is the enzymatic property observed in this case?

A. Specificity of the enzymes

(16)

B. The pH dependence of an enzymatic activity

C. Thermolability of enzymes D. Denaturation of enzymes

E. Effect of inhibitors on an enzymatic activity

12. Methotrexate is a competitive inhibitor of dehydrofolate reductase. It is used for the bladder cancer treatment. On the interaction with which component is the mechanism of action of this drug based on?

A. The active site of the enzyme B. Apoenzyme

C. Allosteric site of the enzyme D. Prosthetic group

E. Substrate

13. What phenomenon is the basis of the mechanism of enzyme’s action?

A. Formation of an enzyme-substrate complex

B. Approximation of functional groups that enter the active site of the enzyme

C. Changing of the spatial configuration D. Changing of the enzyme charge E. Hydrolysis of the enzyme

14. The Michaelis constant is the substrate concentration when the velocity of the reaction is:

A. Maximum B. Minimum

C. A half of the maximum D. A half of the minimum E. One-third of the maximum

15. The absence of a change in the rate of the enzymatic reaction with increasing substrate concentration is associated with:

A. Blocking of the allosteric site B. Denaturation of the enzyme C. Saturation of allosteric site D. Saturation of an active site

E. Increase in the temperature of the medium 16. Acetylcholinesterase is an enzyme that catalyses a breakdown of acetylcholine.

Insecticides, pesticides and poisons with nervously-paralytic action based on fluorophosphates irreversibly inhibit acetylcholinesterase. Specify a mechanism of the inhibition:

A. Inhibitors bind to serine residue in the active site of the enzyme

B. Inhibitors bind to histidine residue in the allosteric site

C. Inhibitors are the structural analogs of the substrate

D. Inhibitors form complex with acetylcholine

E. Inhibitors cause denaturation of the enzyme

17. Digestion of different food components occurs in the duodenum under the influence of pancreatic enzymes. Which of the following enzymes hydrolyses O-glycoside bonds of carbohydrates?

A. Alpha-Amylase B. Carboxypeptidase C. Lipase

D. Trypsin E. Urease

18. Saliva contains an enzyme that has bactericidal effect due to its ability to destroy the peptidoglycan of the bacterial cell wall.

Name this enzyme:

A. Lysozyme (muramidase) B. α-amylase

C. Trypsin D. Phosphatase E. Ribonuclease

19. The structure of the active site of a simple enzyme contains only:

A. Coenzymes B. Co-substrates

C. Radicals of the allosteric site D. Amino acid radicals

E. Radicals of inhibitors in complex with ions of metals

20. In accordance with the Kosland theory, the substrate is able to induce changes in the configuration of an enzyme molecule in accordance with its structure and as a result, binding with the substrate molecule occurs in the active site of an enzyme. What is not a function of the active site?

A. Interaction with effectors

B. Formation of an enzyme-substrate complex C. Catalytic transformation of the substrate D. Specific binding to the substrate

E. ---

(17)

5. Analysis of regulation of enzymic processes.

1. A structural feature of regulatory enzymes is presence of an allosteric site. Specify its role:

A. It changes a structure of a substrate B. It binds a substrate

C. It binds a regulatory effector

D. It promotes a dissociation of a coenzyme E. It binds a coenzyme

2. Organophosphorus compounds are highly toxic poisons with nervously-paralytic action based on an inhibition of an activity of acetylcholinesterase by forming covalent bonds with the OH groups of serine in the active site of an enzyme. What type of the inhibition is characteristic for this class of compounds?

A. Irreversible B. Reversible C. Competitive D. Non-competitive E. Retroinhibition

3. Acetyl-CoA carboxylase is the key enzyme in the synthesis of fatty acids. One way to regulate the activity of Acetyl-CoA carboxylase is feedback inhibition by the final product palmitoyl-CoA. What kind of inhibition feedback inhibition belongs to?

A. Allosteric inhibition B. Competitive inhibition C. Irreversible inhibition

D. Covalent modification of the enzyme E. Non-competitive inhibition

4. Tabun, Sarin and diisopropyl- fluorophosphate are organophosphorus compounds. They are highly toxic poisons with nervously-paralytic action. Which of the following enzymes is inhibited by organophosphorus compounds?

A. Acetylcholinesterase B. Phospholipase A₂

C. Angiotensin converting enzyme D. Tyrosine aminotransferase E. Cytochrome P450

5. Name the type of enzyme inhibition where the chemical structure of an inhibitor resembles the structure of the substrate:

A. Competitive B. Non-competitive C. Uncompetitive D. Substrate E. The irreversible

6. Name the type of enzyme inhibition where the inhibitor binds at a site other than the enzyme's active site:

A. Competitive B. Non-competitive C. Uncompetitive D. Substrate E. Allosteric

7. The anti-inflammatory drug that blocks the action of cyclooxygenase was used for treatment of a patient. What is an anti- inflammatory drug called?

A. Aspirin B. Analgin C. Allopurinol D. Thiamine E. Creatine

8. The transformation of inactive proinsulin into an active one occurs by:

A. Partial proteolysis

B. Attachment of the regulatory subunit C. Changes in the tertiary structure D. Phosphorylation-dephosphorylation E. Attachment of C-peptide

9. The interaction of carbomoyl phosphate and aspartate is the first step in the synthesis of pyrimidine nucleotides in the E. coli cell, which is catalyzed by the enzyme aspartate carbamoyltransferase. The synthesis of pyrimidine nucleotides is stopped under the increasing of the concentration of UTP in the cell. Specify the type of regulation of aspartate carbamoyltransferase:

A. Partial proteolysis B. Allosteric regulation

C. Phosphorylation of an enzyme D. Effect of inhibitory proteins E. Cleavage of inhibitory proteins

10. A patient has an acute pancreatitis. What medications should a doctor prescribe to prevent a pancreatic autolysis?

A. Inhibitors of proteases B. Activators of proteases

(18)

C. Trypsin D. Chymotrypsin E. Amylase

11. A doctor prescribed trasylol (contrykal, gordox) to prevent attacks of acute pancreatitis, which inhibits the activity of:

A. Trypsin B. Chymotrypsin C. Gastricin

D. Carboxypeptidases E. Elastases

12. A patient suffering from tuberculosis was prescribed isoniazid. It is a structural analogue of nicotinamide and pyridoxine.

What type of an inhibition by the mechanism of action isoniazid causes?

A. Competitive B. Irreversible C. Non-competitive D. Allosteric E. Uncompetitive

13. ATP is an effector for the hexokinase that is a regulatory enzyme of glycolysis. As a result of their interaction with the enzyme, structural changes occur and hexokinase loses its catalytic activity. Which structural unit of the enzyme does ATP bind to?

A. Apoenzyme B. Allosteric site

C. Anchor part of the active site D. Catalytic part of the active site E. All of the above

14. Which part of an enzyme the regulators interact with changing enzyme's activity?

A. Anchor part of the active site B. Allosteric site

C. Catalytic part of the active site D. Proenzyme (zymogen)

E. Parallosteric site

15. Salicylates are reversible non-competitive inhibitors of glutamate dehydrogenase.

Choose a method that can be used to reduce a degree of an enzyme inhibition?

A. Reduce the substrate concentration B. Increasing substrate concentration C. To reduce the pH value of the medium D. Enter a structural analog of the substrate E. To reduce a concentration of an inhibitor

16. Which of the following substances activates conversion of pepsinogen into pepsin by a partial proteolysis?

A. Bile acids B. Enterokinase C. NaCl

D. ATP E. HCl

17. What type of inhibition is observed under the use of proserin that is an acetylcholinesterase inhibitor?

A. Reversible B. Competitive C. Non-competitive D. Uncompetitive E. Allosteric

18. What is a competitive inhibitor of succinate dehydrogenase?

A. Malonate B. Alanine C. Succinate D. Fumarate

E. Alfa-ketoglutarate

19. When studying the composition of pancreatic juice, it was found that it contains a large number of enzymes. Some of them are secreted in an inactive form. What are these enzymes?

A. Sucrase, amylase B. Nuclease, Pepsin

C. Trypsinogen, chymotrypsinogen D. Catalase, lipase

E. Nuclease, peptidase

20. In the human body chymotrypsin is secreted by pancreas and converted to an active chymotrypsin by a partial proteolysis in the lumen of the small intestine under the action of:

A. Trypsin B. Enterokinases C. Pepsin

D. Aminopeptidases E. Carboxypeptidases

21. One of the methods of treatment for methanol poisoning is that the patient is prescribed ethanol inside or intravenously in an amount that causes intoxication in a

(19)

healthy person. Why is this treatment effective?

A. Ethanol competes with methanol for the active site of alcohol dehydrogenase

B. Ethanol binds the allosteric site of alcohol dehydrogenase, which is inactivated

C. Ethanol competes with methanol for the allosteric site of alcohol dehydrogenase

D. Ethanol blocks the enzyme alcohol dehydrogenase

E. Ethanol is split faster than methanol, resulting in less toxic products

22. In medical practice teturam is widely used for the prevention of alcoholism. Teturam is an inhibitor of acetaldehyde dehydrogenase.

The increase of what metabolite in the blood, forming during the dehydrogenation of ethanol, causes an aversion to alcohol?

A. Methanol B. Acetoacetate C. Malondialdehyde D. Propionaldehyde E. Acetaldehyde

6. Medical enzymology.

1. It was observed an increased hemolysis of erythrocytes in a 3-year-old child with an increased body temperature after aspirin taking. Congenital insufficiency of what enzyme causes hemolytic anemia?

A. Glucose-6-phosphatase

B. Glucose-6-phosphate dehydrogenase C. Glycogen phosphorylase

D. Glycerolphosphate dehydrogenase E. γ-glutamyltransferase

2. It is found the dark spots on the diaper of a newborn. After identification it is established that it is homogentisinic acid. With the violation of the exchange of what substance is it related?

A. Galactose B. Tyrosin C. Methionine D. Cholesterol E. Tryptophan

3. Dyspepsia is appeared in a newborn baby after the breast-feeding. The symptoms of dyspepsia disappear after the replacing of

milk with glucose solution. The decreased activity of which enzyme is the cause of the indicated disorders?

A. Sucrase B. Lactase C. Maltase D. Amylase E. Isomaltase

4. A 2-year-old child has lag of physical and mental development. The child’s skin and hair is light, the concentration of catecholamines is reduced in the blood. The adding of a few drops of 5% solution of trichloroacetic iron to the fresh urine causes an appearance of the olive-green coloring. The disturbance of the metabolism of what amino acid is the cause of the indicated disorders?

A. Phenylketonuria B. Alkaptonuria C. Tyrosinosis D. Albinism E. Cystinuria

5. Ultrasonic examination of a 10-year-old boy revealed the kidney stones. The concentration of all aliphatic amino acids was high in the blood. What was the most likely pathology?

A. Cystinuria B. Alkaptonuria C. Fanconi syndrome D. Phenylketonuria E. Hartnup disease

6. A patient is diagnosed with alkaptonuria.

The defect of what enzyme causes the pathology?

A. Homogentisate oxidase B. Phenylalanine hydroxylase C. Glutamate dehydrogenase D. Pyruvate dehydrogenase E. Pyruvate carboxylase

7. A sick child is diagnosed with the galactose-1-phosphate uridyltransferase deficiency. What is the most likely pathology?

A. Galactosemia B. Fructosemia C. Hyperglycemia D. Hypoglycemia E. Hyperlactatacidemia

(20)

8. A 1-year-old child has lag of mental development. Vomiting, convulsions and loss of consciousness are observed in the morning.

Hypoglycemia is revealed on an empty stomach. The deficiency of what enzyme is the cause of the indicated disorders?

A. Glycogen synthetase B. Phosphorylase C. Arginase D. Sucrase E. Lactase

9. Laboratory testing of a sick child’s blood revealed a high amount of galactose and decreased concentration of glucose. Lag of mental development and cataract are observed in a child. What is the most likely disease?

A. Diabetes mellitus B. Lactosemia C. Galactosemia D. Steroid diabetes E. Fructosemia

10. A patient is diagnosed with steatorrhea under a laboratory investigation. The deficiency of what enzyme is the cause of the indicated disorder?

A. Chymotrypsin B. Amylase C. Pepsin D. Lactase E. Lipase

11. A patient was brought to the surgical department with a diagnosis of acute pancreatitis. Conservative therapy was started. The prescription of what drug is pathogenetically grounded?

A. Fibrinolysin B. Trypsin C. Chymotrypsin D. Pancreatin E. Contrykal

12. A 7-year-old boy was brought to a clinic with signs of mental and physical retardartion.

The biochemical analysis showed an increased amount of phenylalanine in the blood. The deficiency of what enzyme is the cause of the indicated disorders?

A. Glutamate decarboxylase B. Homogentisate oxidase

C. Glutamintransaminase D. Aspartate aminotransferase E. Phenylalanine-4-monooxygenase

13. Parents of a 3-year-old child paid attention to the darkening of the color of child’s urine in the air. Objectively: the temperature is normal, the skin is pink, clean and the liver is not enlarged. Indicate the most likely pathology:

A. Alkaptonuria B. Hemolysis

C. Cushing syndrome D. Phenylketonuria E. Gout

14. What protease inhibitor used to treat pancreatitis was first isolated from the salivary glands of cattle?

A. Trasylol B. Allopurinol C. Kallikrein D. Amylase E. Lysozyme

15. Laboratory examination of a child revealed a high level of leucine, valine, isoleucine and their keto derivatives in the blood and urine. The urine had a characteristic odor of a maple syrup. The deficiency of what enzyme caused the disease?

A. Dehydrogenase of branched amino acids B. Aminotransferase

C. Glucose-6-phosphatase D. Phosphofructokinase E. Phosfofructomutase

16. Hydrogen cyanide and cyanides are strong poisons. Depending on the dose, death occurs within a few seconds or minutes. The inhibition of what enzyme causes the death?

A. Cytochromoxydase B. Acetylcholinesterase C. ATP synthase D. Catalase

E. Methemoglobinreductase

17. A patient complains of chronic fatigue and dizziness. He works at a chemical plant for the production of hydrocyanic acid. The disorder of what enzyme’s function is the cause of the indicated symptoms?

A. Cytochrome oxidase

(21)

B. Lactate dehydrogenase C. Succinate Dehydrogenase D. Catalase

E. Pyruvate dehydrogenase

18.

A

38-year-old patient is observed an enhanced hemolysis after taking aspirin and sulfanilamides caused by the deficiency of glucose-6-phosphate dehydrogenase. The impaired formation of what coenzyme causes the pathology?

A. NADPH2

B. FADH₂

C. Pyridoxal phosphate D. FMNH2

E. Ubiquinone

19. An 8-month-old child was observed vomiting and diarrhea after taking fruit juices.

The hereditary deficiency of what enzyme causes the disorders?

A. Fructokinase

B. Fructose-1-phosphate aldolase C. Hexokinase

D. Phosphofructokinase E. Fructose-1,6-diphosphatase

20. A high level of phenylpyruvate was found in the urine of a sick child. The content of phenylalanine is 350 mg / l (the norm is about 15 mg / l). What is a probable pathology?

A. Albinism B. Phenylketonuria C. Tyrosinosis D. Alkaponuria E. Gout

21. Under the treatment of a patient’s wound surface of an oral mucosa with hydrogen peroxide, the blood was colored brown instead of foaming. The decrease of the concentration of what enzyme causes such disorders?

A. Catalase

B. Pseudocholinesterase

C. Glucose-6-phosphate dehydrogenase D. Acetyltransferase

E. Methemoglobin reductase

22. A mother noticed a dark staining of urine from her 5-year-old child. There were no bile pigments in the urine. The diagnosis is

alkaponuria. The defect of what enzyme causes this pathology?

A. Decarboxylase of phenylpyruvate B. Phenylalanine hydroxylase C. Tyrosinase

D. Oxydase of hydroxyphenylpyruvate E. Homogentisate oxidase

23. Secretory activity of parotid salivary glands is reduced with age. The activity of what salivary enzyme will be decreased sharply?

A. Maltase B. Lysozyme C. Phosphatase D. Hexokinase E. Amylase

24. Organisms that in the process of evolution have not created protection against H2O2, can live only under anaerobic conditions. Which of the listed enzymes can destroy hydrogen peroxide?

A. Peroxidase and catalase B. Oxygenases and hydroxylases

C. Cytochrome oxidase, cytochrome B5 D. Oxygenase and catalase

E. Flavine-dependent oxidases

25. A 42 year-old man suffering from gout has increased concentration of uric acid in the blood. He was prescribed allopurinol to reduce the level of uric acid. The competitive inhibitor of what enzyme is allopurinol?

A. Xanthine oxidase B. Adenosine deaminase

C. Adenine phosphoribosyltransferase D. Hypoxanthine phosphoribosyltransferase E. Guanine deaminase

26. A 47-year-old man was removed a salivary gland under medical indications. The content of amylase in saliva sharply decreased after the operation. Which gland was removed?

A. Submandibular B. Parotid

C. The palatine D. Gingival E. Sublingual

27. Digestion of proteins in the stomach is the initial stage of protein digestion in the human

(22)

gastrointestinal tract. Name the enzymes involved in the digestion of proteins in the stomach:

A. Enteropeptidase and elastase B. Trypsin and catheptins C. Chymotrypsin and lysozyme D. Pepsin and gastricin

E. Carboxypeptidase and aminopeptidase 28. A 50-year-old woman was brought to a clinic with diagnosis of myocardial infarction.

The activity of what enzyme will be increased during the first two days of the disease?

A. Aspartate aminotransferase B. Alanine aminotransferase C. Alanine aminopeptidase D. LDH4

E. LDH5

29. The activity of lactate dehydrogenase in the patient’s blood is increased in 6 hours after an acute myocardial injury. Which isoform of this enzyme is increased?

A. 1 B. 6 C. 3 D. 4 E. 5

30. A child suffering from Lesch-Nyhan syndrome has a severe form of hyperuricemia, accompanied by the appearance of tophi, urate stones in the urinary tract and severe neuropsychiatric disorders. A decrease in the activity of which enzyme is the cause of this disease?

A. Hypoxanthine-guanine phosphoribosyltransferase

B. Xanthine oxidase C. Hydrofolate reductase D. Thymidylate synthase

E. Carbomoyl phosphate synthetase

31. A 49-year-old patient suffering from acute pancreatitis has a threat of pancreonecrosis development, which was accompanied by the leaking of active pancreatic proteinases into the blood and tissues and the cleavage of tissue proteins. What protective factors of the body can inhibit these processes?

A. Α2-macroglobulin, α1-antitrypsin B. Immunoglobulins

C. Cryoglobulin, interferon

D. Ceruloplasmin, transferrin E. Hemoplexin, haptoglobin

32. Activity of a number of enzymes and their isoforms is determined in the blood for the biochemical diagnosis of myocardial infarction. Which enzyme test is considered the best to confirm or exclude the diagnosis of the myocardial infarction in the early period after the onset of chest pain?

A. MB isoform of creatine phosphokinase B. MM isoform of creatine phosphokinase C. LDH1 isoform of lactate dehydrogenase D. LDH5 isoform of lactate dehydrogenase E. Cytoplasmic isoenzyme of aspartate aminotransferase

33. A study of a secretory function of the stomach revealed a decrease in the concentration of hydrochloric acid in the gastric juice. The activity of which enzyme is reduced in this case?

A. Pepsin B. Amylase C. Lipase D. Dipeptidase E. Hexokinase

34. After taking milk diarrhea, bloating of the intestine were observed in a one-year-old child. What enzyme deficiency caused the symptoms in the baby?

A. Lactase B. Maltase C. Aldolase D. Hexokinase E. Glycosidase

35. A patient has an acute pancreatitis. What drugs prevent the autolysis of the pancreas?

A. Inhibitors of proteases B. Protease activators C. Trypsin

D. Chymotrypsin E. Amylase

36. The increased activities of LDH1,2, AST, MB-isoform of creatine phosphokinase were found in a patient's blood. In which of the following organs is a pathological process probably developed?

A. Cardiac muscle B. Pancreas

(23)

C. The liver D. Kidneys

E. Skeletal muscles

37. In the human body chymotrypsinogen is secreted by the pancreas and converted to an active chymotrypsin by the partial proteolysis in the lumen of the small intestine. What class of enzymes it belongs to?

A. Hydrolases B. Lyases C. Isomerases D. Oxidoreductases E. Synthetases

7. Analysis of the role of cofactors and coenzyme vitamins (В2, РР, В6) in the catalytic activity of enzymes.

1. The doctor prescribed pyridoxal phosphate for a patient according to the clinical indication. For the correction of what pathological processes was this medicine recommended?

A. Transamination and decarboxylation of amino acids

B. Oxidative decarboxylation of keto acids C. Deamination of purine nucleotides D. Synthesis of purine and pyrimidine bases E. Synthesis of protein

2. A patient is diagnosed with pellagra. It is known that the patient ate corn and practically did not eat meat for a long time. Deficiency of which substrate led to this pathology?

A. Tryptophan B. Tyrosin C. Proline D. Alanin E. Histidin

3. A 47-year-old patient suffering from tuberculosis of the upper lobe of the right lung received isoniazid in the combined therapy. After a while, the patient began to complain of a muscle weakness, a decreased skin sensitivity, an impaired vision and coordination of movements. What vitamin should be used to eliminate these symptoms?

A. Vitamin B6

B. Vitamin A C. Vitamin D

D. Vitamin B12

E. Vitamin C

4. A 32-year-old patient is suffering from vitamin B₂ hypovitaminosis. The cause of an occurrence of specific symptoms (defeat of the epithelium, mucous membranes, skin, cornea of the eye) is most likely a deficit of:

A. Flavin coenzymes B. Cytochrome a1

C. Cytochrome oxidase D. Cytochrome b E. Cytochrome c

5. Dermatitis, diarrhea and dementia are observed in a patient. When collecting an anamnesis, it has been turned out that he was a vegetarian. The deficiency of which vitamin caused indicated disorders?

A. Vitamin PP B. Vitamin B1 C. Vitamin B2 D. Vitamin H E. Vitamin C

6. A doctor prescribed isoniazid for a 39-year- old patient suffering from tuberculosis of the lungs. The deficiency of what vitamin could be developed due to prolonged use of this drug?

A. Pyridoxine B. Thiamine C. Cobalamin D. Biotin E. Folic acid

7. Dermatitis, diarrhea and dementia were revealed during medical examination of a patient. The absence of which vitamin caused such clinical symptoms?

A. Nicotinamide B. Ascorbic acid C. Folic acid D. Biotin E. Rutin

8. The symptoms of pellagra (vitamin PP deficiency) are particularly pronounced in the patients obtaining a low protein diet, because one of the essential amino acids is a precursor of nicotinamide in the human body. What is this amino acid?

A. Tryptophan

(24)

B. Threonine C. Arginine D. Histidine E. Lysine

9. The activity of blood transaminases is determined for the diagnosis of certain diseases. Which vitamin is a cofactor of these enzymes?

A. B6

B. B2

C. B₁ D. B12

E. B_с

10. The structural analogs of vitamin B₂ (riboflavin) are prescribed for the patients suffering from malaria. Violations of the synthesis of what enzymes in plasmodium are caused by using of these drugs?

A. FAD-dependent dehydrogenases B. Cytochrome

C. Peptidase

D. NAD-dependent dehydrogenases E. Aminotransferase

11. Which vitamin is the precursor of NAD⁺ and NADP⁺ coenzymes?

A. РР B. В2

C. В12

D. В3

E. В1

12. The patient has a decreased appetite, diarrhea, pallor and dry skin, cyanosis of the lips, cheeks and hands. The tongue is shiny

"lacquer", its edema is observed (teeth marks are visible around the edges). The deficiency of which vitamin is observed?

A. PP B. В2

C. В1

D. В3

E. В12

13. Muscle weakness, irritability, skin lesions, hair loss and anemia are observed in a patient under the tuberculosis treatment with isoniazid. The deficiency of which vitamin caused the disorders?

A. В6

B. В2

C. В12

D. В3

E. В1

14. Oxidoreductases are the first class of enzymes. What are their coenzymes?

A. NAD, NADP, FAD, FMN B. Methylcobalamin, THF

C. TGF, CoA, 4-phosphopantetein D. TPP, carboxibiotin

E. TPP, pyridoxal-5-phosphate

15. These coenzymes are prosthetic groups of oxidoreductases, part of succinate dehydrogenase and xanthine oxidase. What are they?

A. FAD, FMN B. NAD, NADP C. THF

D. TPP E. CoA

16. This is the most important coenzyme in the metabolism of amino acids. It is a part of transaminases and decarboxylases of amino acids. What is the coenzyme called?

A. Pyridoxal-5-phosphate B. NAD, NADP

C. THF D. TPP E. CoA

17. This vitamin is involved in all types of metabolism. Funicular myelosis and megaloblastic anemia are developed under its absence. What is this vitamin?

A. Thiamine B. Pyridoxine C. Riboflavin D. Biotin E. Cobalamin

8. Analysis of the role of cofactors and coenzyme vitamins (В3, Вс, В1, В12,Н, lipoic acid) in the catalytic activity of enzymes.

1. Oxidative decarboxylation of α-ketoglutaric acid is decreased as a result of vitamin B₁ deficiency. The synthesis of which of the following coenzymes is disordered in this case?

A. Coenzyme A

(25)

B. Nicotinamide adenine dinucleotide C. Flavin adenine dinucleotide

D. Lipoic acid

E. Thiamine pyrophosphate

2. A patient is suffering from the disrupted absorption of vitamin B12 after operative removal of a part of stomach. Anemia has been developed in the patient. Which factor is necessary for the absorption of this vitamin?

A. Castle’s intrinsic factor B. Gastrin

C. Hydrochloric acid D. Pepsin

E. Folic acid

3. Concentration of pyruvate is increased in the patient's blood. A significant amount of it is excreted in the urine. The deficiency of what vitamin is developed in a patient?

A. B2

B. E C. B3

D. B6

E. B₁

4. The cause of pellagra can be preferential feeding of corn and reduction in the diet of products of animal origin. Absence of which amino acid in the diet leads to this pathology?

A. Tryptophan B. Tyrosine C. Proline D. Alanine E. Histidine

5. After the removal of the 2/3 of the patient's stomach it has been observed the decreased content of hemoglobin and red blood cells in the blood. The megaloblastic cells are appeared in the blood test. The deficiency of what vitamin leads to such changes?

A. B12

B. C C. P D. B₆ E. PP

6. Cocarboxylase (thiamine pyrophosphate) is used for the treatment of many diseases, normalizing energy metabolism. Which process is activated?

A. Oxidative decarboxylation of pyruvate

B. Deamination of glutamate C. Decarboxylation of amino acids D. Deamination of biogenic amines

E. Detoxification of xenobiotics in the liver 7. Addison-Biermer disease is a malignant hyperchromic megaloblastic anemia. It is caused by the deficiency of vitamin B12. Which microelement is a part of the vitamin?

A. Cobalt B. Molybdenum C. Zinc

D. Iron

E. Magnesium

8. A worker of the poultry factory consuming 5 or more raw eggs every day complains of the weakness, drowsiness, pain in the muscles, hair loss and seborrhea. The deficiency of what vitamin is the cause of this state?

A. H (biotin)

B. C (ascorbic acid) C. A (retinol) D. B₁ (thiamine) E. B₂ (riboflavin)

9. Hyperpyruvatemia was revealed in the patient. The deficiency of what vitamin is observed in the patient?

A. B1

B. E C. B3

D. B6

E. B₂

10. A 4-year-old child has been delivered to a hospital with symptoms of paresis of the lower limbs. It was revealed an anemia, high concentration of methylmalonate in the blood.

The lack of what vitamin caused these symptoms?

A. Cobalamin B. Pantothenic acid C. Vitamin A D. Niacin E. Biotin

11. A 55-year-old man suffering from alcoholic liver cirrhosis was diagnosed with megaloblastic anemia. The deficiency of what vitamin caused development of anemia?

A. Lipoic acid

(26)

B. Folate C. Biotin D. Riboflavin E. Pantothenic acid

12. Some amino acids, vitamin derivatives and phosphoric esters of ribose are involved in the biosynthesis of purine nucleotides. The coenzyme form of which vitamin is a carrier of one-carbon fragments in the synthesis of purine nucleotides?

A. Folate

B. Pantothenic acid C. Niacin

D. Riboflavin E. Pyridoxine

13. A patient was diagnosed with seborrheic dermatitis associated with the deficiency of vitamin H (biotin). The reduced activity of which enzyme is observed in the patient?

A. Acetyl-CoA carboxylase B. Pyruvate decarboxylase C. Alcohol dehydrogenase D. Aminotransferase

E. Сarbamoyl phosphate synthetase

14. A patient suffering from atrophic gastritis was diagnosed with megaloblastic anemia.

The deficiency of which compound caused the development of anemia?

A. Gastromucoprotein (Castle factor) B. Vitamin B6

C. Vitamin B1

D. Iron

E. Erythropoietin

15. Steatosis is caused by an accumulation of triacylglycerols in hepatocytes. What lipotropic substances prevent the development of liver steatosis?

A. Methionine, B₆, B₁₂ B. Arginine, B2, B3

C. Alanine, B1, PP D. Valine, B₃, B₂ E. Isoleucine, B₁, B₂

16. Vitamins taking part in the biochemical processes of the body are synthesized by the normal microflora of the large intestine. What vitamins are synthesized primarily by microorganisms?

A. E, PP

B. A, C C. K, B₁₂ D. B1, B2

E. B6, E

17. What vitamins are necessary for the reactions of the Krebs cycle?

A. В1, В2, В3, РР B. Вс, В12, В15, А C. D, К, С, В15 D. Е, Р, В15

E. С, В12, D, К

18. Which of the following vitamins is essential for fatty acid synthesis?

A. Biotin B. Folate C. Niacin

D. Ascorbic acid E. Cobalamine

19. Which of the following vitamins provides a cofactor for transfer of one-carbon units?

A. Riboflavin B. Pyridoxine C. Niacin D. Folate E. Thiamin

20. Megaloblastic anemia has two most likely causes, deficiency of folate and deficiency of cobalamin. Often treatment of patients with cobalamin deficiency improves in terms of their hematologic features with treatment with folate but not in their neurologic symptoms.

What is the most likely explanation for this?

A. Excess of folate blunts the trapping of folate as N5-methyltetrahydrofolate

B. Cobalamin deficiency is not serious

C. Folate in high concentrations can serve as a cofactor for the conversion of homocysteine to methionine

D. Excess of folate directly inhibits the destruction of red blood cells

E. Excess of folate stimulates erythropoietic tissues to synthesize cobalamin in situ

21. A patient was diagnosed with the vitamin H (biotin) deficiency. The reduced activity of which of the following enzymes is observed in the patient?

A. Pyruvate carboxylase B. Pyruvate decarboxylase

(27)

C. Alcoholdehydrogenase D. Aminotransferase

E. Carbamoyl phosphate synthetase

9. Basic concepts of metabolism. Common catabolic pathways of proteins, carbohydrates and lipids.

1. Bioenergetics of the brain is significantly dependent upon oxygen supply. What substrate of oxidation is the main energy source for neurons?

A. Glucose B. Fatty acids C. Ketone bodies

D. Glycerol-3-phosphate E. Phosphoenolpyruvate

2. Exergonic metabolic reactions take place with:

A. Energy release B. Energy absorption C. Heat generation D. Absorption of heat E. ATP absorption

3. Endergonic metabolic reactions take place with:

A. Energy absorption B. Energy release C. Heat generation D. Absorption of heat E. ATP absorption

4. Indicate the category of metabolism, which is characterized by processes of synthesis of complex substances from simpler ones with energy absorption:

A. Catabolism B. Anabolism

C. Amphibolic pathway D. Dualism

E. Anaplerotic reactions

5. Indicate the category of metabolism, which is characterized by processes of breakdown of complex substances to simpler ones with energy release:

A. Anabolism B. Catabolism

C. Amphibolic pathway D. Dualism

6. Amphibolic process serves as a source of metabolites for:

A. Anabolic processes B. Catabolic processes

C. Both anabolic and catabolic processes D. Protein synthesis

7. What type of membrane transport requires ATP?

A. Facilitated diffusion B. Simple diffusion C. Osmosis

D. Filtration E. Active transport

8. In which cellular compartment does the third stage of catabolism occur?

A. Mitochondria B. Nucleous C. Cytosol D. Lysosomes E. Golgi apparatus

9. What biochemical process of general pathway of catabolism of proteins, lipids and carbohydrates produces carbon dioxide as an end product of metabolism?

A. Krebs circle B. Glycolysis

C. Tissue respiration D. Gluconeogenesis E. Lipolysis

10. What biochemical process of general pathway of catabolism of proteins, lipids and carbohydrates produces water as an end product of metabolism?

A. Tissue respiration B. Krebs circle C. Glycolysis D. Gluconeogenesis E. Lipolysis

11. How many percents of the chemical energy of the substance are transformed into ATP during its oxidation?

A. 42 B. 30 C. 20 D. 65