bc Flashcards by yash p

1.Which of the following amino acids supply the
atoms of positions 1,4,5 and 6 of the pyrimidine ring
in the de novo pyrimidine biosynthesis:
a) glycine
b) aspartate
2.c) glutamine
3.d) glutamate

aspartate

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In which the following catabolic processes amino acids are converted to the
corresponding α keto-acids (C-skeletons).
1) oxidative deamination
2) degradation of the carbon backbone
3) transamination
4) decarboxylation
a) 1 + 2 + 3
b) 1 + 3
c) 2 + 4
d) 4

b. 1+3

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Which of the following statements about the activation of the urea
cycle is
wrong:
a) urea cycle is activated during periods of fasting
b) the urea cycle is activated upon allosteric activation of the regulatory
enzyme (carbamoyl phosphate synthetase I) from N-acetyl-glutamate
c) the urea cycle is activated upon induction of the synthesis of enzymes
involved in the urea cycle
d) urea cycle is activated after meal with low protein content

d) urea cycle is activated after meal with low protein content

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Which of the following cofactors serve as prosthetic groups of the
enzymes aminoacidooxidases which catalyze the oxidative deamination
of amino acids:
1) NAD+
2) FMN
3) NADP+
4) FAD
a) 1 + 2 + 3
b) 1 + 3
c) 2 + 4
d) 4

b) 1 + 3

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For the synthesis of which of these molecules (neurotransmitters and
hormones) the amino acid tyrosine is not a precursor (substrate):
a) dopamine
b) serotonin
c) catecholamines (norepinephrine and epinephrine)
d) thyroid hormones

b) serotonin

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Which of the following statements about the synthesis of heme in
mammalian cells is true?
a)succinyl CoA and alanine are direct substrates for the formation of 5-
aminolevulinic acid (5-Ala)
b) Ferric ions (Fe3 +) are introduced into protoporphyrin IX
c) Coproporphyrin IV is an intermediate metabolite
d) Porphobilinogen is formed due to the condensation of 2 molecules of
5- Ale

d) Porphobilinogen is formed due to the condensation of 2 molecules of
5- Ale

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Patients with reduced intake of bilirubin from hepatocytes A) have an
increased level of “indirect” bilirubin in the blood B) have an increased
level of “direct” bilirubin in the blood
a) А
b) B
c) A and B
d) neither А nor B

d) neither А nor B

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In enzyme defect (deficiency) 5-Ala dehydratase (porphobilinogen
synthase) the following clinical signs are observed:
a) severe abdominal pains thrusts or
b) skin photosensitivity

a) А
b) B
c) A and B
d) neither А nor B

b.b

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In the synthesis of heme in mammalian cells:

1) Uroporphyrin III is the direct predecessor of coproporphyrin III
2) Ala-5 is formed by the condensation of succinyl CoA and valine
3) The ferric ion (Fe3 +) is introduced into the protoporphyrin IX before its
binding to globin molecule
4) Porphobilinogen formed due to the condensation of 2 molecules of 5-Ale
a)1 + 2 + 3
b) 1 + 3
c) 2 + 4
d) 4

b) 1 + 3

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In the metabolism of iron:

1) during the passage of the ferrous ions (Fe2 +) from the enterocytes in the
blood they are oxidized to ferric ions (Fe3 +) under the action of
tserulopazmin
2) the main transport protein of iron in plasma is hemosiderin
3) in the form of a complex with the protein ferritin iron accumulates in the
cells of the intestinal mucosa, liver, bone marrow
4) almost all of the iron from the diet is absorbed and excess is excreted in
the faeces
a) 1 + 2 + 3
b) 1 + 3
c) 2 + 4
d) 4

b) 1 + 3

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Increase in the blood of “direct” bilirubin is expected in:
1) hemolytic jaundice
2) low activity of Bilirubin-UDP-glucuronyl transferase as it is in infants
3) decreased hepatic intake of bilirubin (Gilbert syndrome)
4) biliary obstruction (blockage)
a) 1 + 2 + 3
b) 1 + 3
c) 2 + 4
d) 4

a) 1 + 2 + 3

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Ale synthetase:

1) requires pyridoxalphosphate for its activation
2) the synthesis of the enzyme may be induced by phenobarbital and some
of the steroids
3) suppressed by catarrh
4) is inhibited by lead
a) 1 + 2 + 3
b) 1 + 3
c) 2 + 4
d) 4

a) 1 + 2 + 3

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Thioredoxin is involved in:

a) the conversion of ATP into ADP
b) the conversion of dUMF into dTMF
c) the conversion of ribonucleotides into deoxyribonucleotides
d) the inhibition of xanthine oxidase

a) the conversion of ATP into ADP

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Which of the following mechanisms performes control the de novo synthesis
of pyrimidine nucleotides in humans:

1) negative feedback of glutamine-PRPP-amidotransferase
2) negative feedback of aspartate transcarbamoylase
3) availability of N-acetyl glutamate
4) availability of PRPP
a) 1 + 2 + 3
b) 1 + 3
c) 2 + 4
d) 4

d) 4

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Methotrexate is an inhibitor of dihydrofolate reductase. Its application
would inhibit:
1) de novo synthesis of UMP
2) conversion of dUMP into dTMP
3) conversion of IMP into GMP
4) de novo synthesis of IMP
a) 1 + 2 + 3
b) 1 + 3
c) 2 + 4
d) 4

c) 2 + 4

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Aspartic acid plays a role in all of the following processes with the
exception of one. Which is it?

a) de novo synthesis of AMP
b) the conversion of ATP into CTP
c) de novo synthesis of orotic acid
d) maintaining the pool (reservoir) of adenine nucleotides through
alternative pathways

c) de novo synthesis of orotic acid

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From the amino acid Trp (tryptophan) are obtained following biologically
important compounds

1) thyroxine
2) melanin
3) dopamine
4) melatonin
a) 1 + 2 + 3
b) 1 + 3
c) 2 + 4
d) 4

d) 4

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End products of the N-metabolism, which are excreted from the body
are:
1) urea
2) creatine
3) uric acid
4) acetoacetate
a) 1 + 2 + 3
b) 1 + 3
c) 2 + 4
d) 4

a) 1 + 2 + 3

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Metabolites of Ornithine cycle are:
1) succinyl CoA
2) citrulline
3) 5- Aminolevulinic acid
4) carbamoyl phosphate
a) 1 + 2 + 3
b) 1 + 3
c) 2 + 4
d) 4

c) 2 + 4

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Pyrimidines degradation products are:
1) b-aminoisobutyrate
2) urea
3) b-alanine
4) orotic acid
a) 1 + 2 + 3
b) 1 + 3
c) 2 + 4
d) 4

d) 4

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Regulatory enzymes of purines de novo synthesis are:
1) xanthine oxidase
2) PRPP amidotransferase
3) adenine phosphoribosyltransferase
4) adenilosuccinate synthetase
a) 1 + 2 + 3
b) 1 + 3
c) 2 + 4
d) 4

d.4

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Which of the following enzymes is defective in patients with Lesch-Nyhan
syndrome?

a) adenosine deaminase
b) adenine phosphoribosyltransferase (АPT)
c) xanthine dehydrogenase (oxidase)
d)hypoxanthineguaninephosphoribosyltransferase (HGPRT)

d)hypoxanthineguaninephosphoribosyltransferase (HGPRT)

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Which of the following groups of amino acids can be classified as “non-
essential”?

a) Ala, Glu, Ile, Pro
b) Asn, Cys, Pro, Tyr
c) Ast, Ser, Thre, Tyr
d) Ala, Gln, Gly, Trp

b) Asn, Cys, Pro, Tyr

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Tetrahydrobiopterin is required to:
a) methylation of dUMP
b) degradation of Tyr
c) hydroxylation of phenylalanine
d) transfer of one-carbon groups (fragments)

c) hydroxylation of phenylalanine

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Hereditary metabolic disorder known as Phenylketonuria (PKU): a)is usually due to a hereditary defect of the enzyme phenylalanine hydroxylase b) is related to a high level of phenylalanine and tyrosine in blood plasma c) manifests in young boys d) associated with blond hair and a light tan because phenylalanine inhibits the production of melanin

a)is usually due to a hereditary defect of the enzyme phenylalanine hydroxylase

Which of the following amino acids are precursors in the synthesis of creatine phosphate? 1) Glycine 2) methionine 3) arginine 4) glutamine a) 1 + 2 + 3 b) 1 + 3 c) 2 + 4 d) 4

b) 1 + 3

Transamination reactions require one of the following vitamins a) riboflavin b) pantothenate; c) thiamine; d) pyridoxol;

d) pyridoxol;

Which of the following vitamins is a precursor of prosthetic groups of transaminases? а) thiamine b) pyridoxine c) niacin d) riboflavin

b) pyridoxine

In which of the following diseases is observed increased levels of GOT(АsАТ)?. 1. obstructive jaundice 2. viral hepatitis 3. brain stroke 4. cardiac infarction a) 1+2+3 b) 1+3 c) 3+4 d) 1+2+4

d) 1+2+4

Which of the following enzymatic defects is responsible for the Crigler- Naijar syndrome? а) argininosuktsinat synthetase deficiency b) bilirubin UDP-glucuronyl-transferase deficiency c) Pal-hydroxylase deficiency d) biopterin synthase deficiency

b) bilirubin UDP-glucuronyl-transferase deficiency

Reactions of disposal of ammonia in peripheral tissues are 1) glutamine synthase reaction 2) urea synthesis 3) reductive amination of alpha-ketoglutarate 4) amidoacidooxidase reaction a) 1 + 2 + 3 b) 1 + 3 c) 2 + 4 d) 4

b) 1 + 3

Which of the following compounds is obtained from tryptophan as one of the reactions in its synthesis is a reaction of decarboxylation? a) dopamine b) melatonin c) epinephrine d) histamine

b) melatonin

Which of these amino acids is only ketogenic amino acid? а) tryptophan b) leucine c) isoleucine d) alanine

b) leucine

Which of the following enzymes catalyze reactions of disposal (fixing) of ammonia? 1. glutamate dehydrogenase 2. carbamoyl phosphate synthetase 3. glutamine synthetase 4. glutaminase а) 1+2+3 b) 2+3 c) 2+4 d) 1+2+4

c) 2+4

Which of the following reactions from Ornithine cycle is endergonic and requires ATP? а) ornithine transcarbamoylase b) argininosuccynate synthetase c) argininosuccynate lyase d) arginase

c) argininosuccynate lyase

Which of the following compounds accumulate in the blood and is excreted in the urine in argininosuccynate synthetase block? a) arginine b) argininosuccynate c) citrulline d) ornithine

a) arginine

37. To which of the following metabolites some of glycogen amino acids are degraded? 1. pyruvate 2. acetoacetate 3. oxaloacetate 4. fumarate a) 1+2+3 b) 2+3 c) 2+4 d) 1+3+4

d) 1+3+4

Which of these amino acids is only ketogenic amino acid? а) tryptophan b) leucine c) isoleucine d) alanine

b) leucine

In block of which of the following enzymes develops classical phenylketonuria? a) homogentisate oxidase b) tyrosine transaminase c) dihydrobiopterin reductase d) phenylalanine hydroxylase

d) phenylalanine hydroxylase

Which of the following biologically important compounds are byproducts from the metabolism of tryptophan? 1. thyroxine 2. melatonin 3. melanin 4. serotonin a) 1+2+3 b) 2+3 c) 2+4 d) 1+3+4

c) 2+4

Which of the following enzymes involved in the synthesis of heme is the major regulatory enzyme regulated by the type of feedback at the genetic level? a) aminolevulinate dehydratase b) aminolevulinate synthase c) uroporphyrinogen III co-synthase d) uroporphyrinogen decarboxylase

b) aminolevulinate synthase

Which of the following biologically important compounds are byproducts from the metabolism of tyrosine? 1. thyroxine 2. melatonin 3. melanin 4. dopamine a) 1+2+3 b) 2+3 c) 2+4 d) 1+3+4

d) 1+3+4

Which of the following one-carbon groups bind to tetrahydrofolic acid (FAH4) is the most reduced (C atom has the lowest oxidation state)? a) formyl (N10- formyl -FAН4) b) methyl (N5- methyl -FAН4) c) methylene (N5 ,N10- methylene -FAН4) d) formimine (N5- formimine -FAН4)

b) methyl (N5-methyl-FAH4)

Which of the following compounds are byproducts, not precursors in the synthesis of heme? 1. 5-Aminolevulinic acid 2. coproporphyrinogen I 3. porphobilinogen 4. uroporphyrinogen I a) 1+2+3 b) 2+4 c) 2+3 d) 1+3+4

b) 2+4

Which of the following substituents and sequence of these substituents at pyrrole ring are found in the precursor of heme coproporphyrinogen? A – acetyl P – propionyl M – methyl V - vinyl a) MB МV МP PМ b) МP МP МP МP c) МP МP МP PМ d) АP АP АP PА

d) АP АP АP PА

50. In which the following catabolic pathways of amino acids "biogenic amines" are produced as end products: a) oxidative deamination b) transamination c) cleavage of the carbon backbone d) decarboxylation

a) oxidative deamination

Which of the following enzymes are involved in the degradation of heme and the production of unconjugated bilirubin? 1) UDP- glucuronyl transferase 2) hemoxigenase 3) biliverdin reductase 4) bilirubin monoglucuronide mutase a) 1+2+3 b) 2+4 c) 2+3 d) 1+3+4

c) 2+3

Defect (complete absence of activity) of which of the following enzymes is responsible for the development of the disease Crigler- Najjar I? а) UDP- glucuronyl transferase b) hemoxigenase c) biliverdin reductase d) bilirubin monoglucuronide mutase

а) UDP- glucuronyl transferase

Which of the following compounds is a bile pigment found in the urine in mechanical (obstructive) jaundice? a) urobilinogen b) sterkobilinogen c) conjugated bilirubin d) unconjugated bilirubin

c) conjugated bilirubin

Considering that the zymogen forms represent the inactive enzyme digesting dietary proteins, which of the following zymogens is not converted into active enzyme by the action of trypsin: a) chymotrypsinogen b) pepsinogen c) proelastase d) procarboxypeptidase

b) pepsinogen

Which of the processes listed below is not endergonic? А. muscle contraction B. transportation of compounds along the concentration gradient C. transmission of a nerve impulse D. maintaining of a concentration gradient

D. maintaining of a concentration gradient

Which of the following statements related to the Second law of the Thermodynamics is wrong? A. Naturally all processes proceed in the direction leading to a maximum disorder. B. A system is in equilibrium (is most stable) when the Enthalpy has a maximum value C. The systems in equilibrium have maximum Entropy. D. The magnitude, characterizing the change of energy that can do work is the Free energy

B. A system is in equilibrium (is most stable) when the Enthalpy has a maximum value

The standard redox potentials (Ео’) of the redox systems NAD+/NAD.H and pyruvate/lactate are: Eo = -0,32 V and Eo = -0,19 V, respectively. Which of the following statements is wrong? A. Under standard conditions, pH 7 and equimolar concentration of 1M of all components of the systems, the redox system NAD+/NAD.H has a greater ability to give electrons than the redox system pyruvate/lactate. B. Under standard conditions, pH 7 and equimolar concentrations of 1M of all the substances, the electrons flow from NAD.H to pyruvate. C. If at the beginning of the reaction the concentration of all substances is 1M, and the pH=7, the reversible reaction: pyruvate + NAD.H+H+ lactate + NAD+, will run from left to right D. If at the beginning of the reaction the concentration of all substances is 1M, and the pH=7, the reversible reaction: pyruvate + NAD.H+H+ lactate + NAD+, will run from right to left

B. Under standard conditions, pH 7 and equimolar concentrations of 1M of all the substances, the electrons flow from NAD.H to pyruvate.

When you consider the standard redox potentials (Eo’) on these three redox systems: 1) Cytochrome.b6 (Fe3+)/ Cytochrome b6 (Fe2+) - Eo’= - 0,06V 2) Cytochrome f (Fe3+)/ Cytochrome f (Fe2+) - Eo= + 0,365V 3) Ferredoxin (oxidized)/ Ferredoxin (reduced) - Eo= - 0,432V which of the following redox chains is correct? А. 1, 2, 3 B. 1,3,2 C. 3, 2, 1 D. 3, 1, 2

C. 3, 2, 1

5. Which of the following bonds are rich in energy (macroergic)? 1) thioester bonds 2) phosphosulfate bonds 3) pyrophosphate bonds 4) phosphodiester bonds А: 1+2+3 B: 1+3 C: 2+4 D: all four

D: all four

6. Which of these magnitudes and values determine the standard free energy of an oxidoreductase process? 1) The number of electrons transferred during the reaction 2) The Faraday constant (F) 3) The difference between the normal redox potentials of redox systems 4) The universal gas constant (R) А: 1+2+4 B: 1+3+4 C: 1+2+3 D: all four

B: 1+3+4

7. Which of the following types of oxidoreductases have most often Vit B2 derivatives as cofactors? A. Peroxidases B. Oxidase C. Monooxygenase D. Anaerobic dehydrogenases

B. Oxidase C. Monooxygenase

8. Which of the following enzymes is involved in the elimination of H2O2? * A: Glutathione peroxidase * B: Superoxide dismutase * C: Glutathione reductase * D: Ham oxygenase

* A: Glutathione peroxidase * B: Superoxide dismutase

9. The listed cytochromes are involved in the respiratory chain in mitochondria. There is only one exception. What is that exception? А: Cytochrome с1 B: Cytochrome с C: Cytochrome b5 D: Cytochrome а3

C: Cytochrome b5

10. Which of the listed redox systems of biological interest is a quinine redox system? A: NAD+/NAD.H B: Glutathione C: Vitamin С D: Coenzyme Q

A: NAD+/NAD.H

11. Which of the listed redox systems of biological interest is a thiol redox system? А: Glutathione B: FAD C: NAD+ D: Vitamin С

D: Vitamin С

Which of the following oxidoreductases function only as anaerobic dehydrogenases? А: the enzymes cooperated with flavonic redox system (FAD or FMN) B: the enzymes cooperated with nicotinamide redox systems (NAD+ or NADP+) C: oxidases D: oxygenases

B: the enzymes cooperated with nicotinamide redox systems (NAD+ or NADP+)

Which of the following oxidoreductases are monooxygenases? 1) Cytochrome oxidase 2) Phenylalanine hydroxylase 3) Tryptophan oxygenase 4) Tryptophan hydroxylase A: 1+2+3 B: 1+3 C: 2+4 D: only 4

C: 2+4

Which of the following substances are direct hydrogen donors in the processes catalyzed by peroxidases for elimination of H2O2 and/or hydroperoxides? 1) Ascorbic acid (Vit С) 2) Tocopherols (Vit E) 3) Glutathione 4) NADP.H А: 1+2+3 B: 1+3 C: 2+4 D: all four

B: 1+3

Which of the following substances is a specific inhibitor of the electron transport performed by the complex IV of the respiratory chain? A. Oligomycin B. Atractiloside C. Malonate D. CO

D. CO

Which of the listed process in the respiratory chain will be inhibited in the presence of the antibiotic oligomycin? A. Cell respiration (redox processes in the respiratory chain) B. Transfer of phosphate ions through the inner mitochondrial membrane C. Transfer of ADP/ATP through the inner mitochondrial membrane D. Synthesis of ATP

D. Synthesis of ATP

Indicate which of the following inhibitors of oxidative phosphorylation in respiratory chain inhibite the transport across the inner mitochondrial membrane of ATP and ADP: А: Atractyloside B: Rotenone C: Oligomycin D: Malonate

C: Oligomycin

The truncated (short) electron transport chains involved in the process of hydroxylation with Cytochrome P450 (CYP) are located mainly in one type of the listed subcellular structures. Which are those structures? А: lysosomes B: peroxisomes C: nuclei D: endoplasmic reticulum

D: endoplasmic reticulum

Indicate which of the following compounds is an uncoupling agent of oxidative phosphorylation in the respiratory chain? А: Rotenone B: 2,4-dinitrophenol C: Oligomycin D: Atractyloside

C: Oligomycin

All listed enzymes, except for only one type, are flavoproteins (FAD/FMN-associated dehydrogenases): A: D-amino acid oxidase B: malate dehydrogenase C: NAD+-dehydrogenase D: succinate dehydrogenase

B: malate dehydrogenase

Which of the following processes are processes of “free oxidation”: 1: hydroxylation with Cytochrome Р450 (CYPs) 2: oxidation of glyceraldehyde 3-phosphate 3. oxidative deamination of amino acids 4: oxidation of lactate A: 1+2+3 B: 1+3 C: 2+4 D: none of them

D: none of them

Which of the listed processes leads to elimination of the superoxide anion radicals: А: reaction catalyzed by NADPH-oxidase B: spontaneous oxidation of hemoglobin C: reaction catalyzed by superoxide dismutase D: reaction catalyzed by xanthine oxidase

C: reaction catalyzed by superoxide dismutase

25. In which of the listed subcellular structures the enzyme catalase is localized? А: peroxisomes B: lysosomes C: mitochondria D: nuclei

А: peroxisomes

Which of the following statements concerning ubiquinone (Q) is wrong? A: In its reduced form, the coenzyme Q (ubiquinone) reacts with Fe-S complexes of ubiquinone- cytochrome c oxidoreductase and transfers one electron on them. B: The quinone structure of the molecule can bind one electron forming condition called free radical semiquinone. C: In the respiratory chain it is reduced by the ubiquinone-cytochrome c oxidoreductase and is oxidized by cytochrome c oxidase D: In mammals its molecule typically has a hydrophobic "tail" made up of 10 isoprene residues

A: In its reduced form, the coenzyme Q (ubiquinone) reacts with Fe-S complexes of ubiquinone- cytochrome c oxidoreductase and transfers one electron on them.

NAD+ and Ubiquinone (Q) serve as collectors of reducing equivalents released during the dehydrogenation of a variety of substrates. These reducing equivalents further are transmitted from reduced ubiquinone (QH2) in the respiratory chain to cytochromes. Indicate which of the listed metabolites are oxidized in the mitochondria yielding NAD.H, which is a major substrate of respiratory chain. 1: isocitrate 2: glycerol-3-phosphate 3. malate 4: succinate A: 1+2+3 B: 1+3 C: 2+4 D: all four

B: 1+3

All lised chemical bonds are macroergic except one. Which is that bond?: А: Pyrophosphate bond B: Thioester bond C: Enolphosphate bond D: Glycosidic bond

D: Glycosidic bond

Which of the following processes are processes of free oxidation: 1: hydroxylation with Cytochrome Р450 (CYPs) 2: oxidation of hypoxanthine 3. oxidative deamination of amino acids 4: oxidation of glyceraldehyde 3-phosphate A: 1+2+3 B: 1+3 C: 2+4 D: none of them

D: none of them

Which of the following substances carry out their antioxidant function mainly by reduction of tocopheryl radical to tocopherol? 1: b-carotene 2: Vitamin C 3: Vitamin A 4: flavonoids A: 1+2+3 B: 1+3 C: 2+4 D: all of them

B: 1+3

Which of the listed processes does not lead to production of superoxide anion radical: A: reaction catalyzed by NADPH-oxidase B: spontaneous oxidation of hemoglobin C: reaction catalyzed by superoxide dismutase D: reaction catalyzed by xanthine oxidase

C: reaction catalyzed by superoxide dismutase

Choose the correct statement, referring to the eukaryotic mitochondrial ATP synthase complex A: ATP from ADP and inorganic phosphate (Pi) is synthesized in the F1 fragment B: The electron microscopic observations show that the F1 fragment of the complex binds to the transmembrane Fo fragment and it is placed on the outer side of the inner mitochondrial membrane c: The antibiotic oligomycin binds the Fo fragment and inhibits the flow of H+ out of mitochondria D: The synthesis of ATP is carried out in the F1 fragment of the complex, and it is a result of oxidative phosphorylation of substrate level

c: The antibiotic oligomycin binds the Fo fragment and inhibits the flow of H+ out of mitochondria

The adding of 2,4-dinitrophenol to the active "breathing" mitochondria causes the effects given below except one of them. Which is that exception? А: [NAD+] is increased B: There is enhancement of ATP production C: There is enhancement of О2 consumption D: Annulling of proton (H+) gradient

B: There is enhancement of ATP production

Indicate which of these cytochromes are not involved in the truncated (microsomal) electron- transfer chains: 1: Cytochorme b5 2: Cytochrome c 3: Cytochrome Р450 4: Cytochrome а3 А: 1+2+3 B: 1+3 C: 2+4 D: all of them

C: 2+4

Which of the following statements concerning respiratory chain is wrong? A: Ubiquinone is a lipid-soluble component of respiratory chain. B: The reduction of molecular O2 is performed in Cytochrome c oxidase complex. C: The arrangement of the redox systems in respiratory chain enables the transmission of electrons from NAD.H+H+ and FAD.H2 to O2, which otherwise is thermodynamically impossible D: The two enzymes: NAD.H - dehydrogenase and Succinate dehydrogenase transfer electrons to coenzyme Q (ubiquinone).

C: The arrangement of the redox systems in respiratory chain enables the transmission of electrons from NAD.H+H+ and FAD.H2 to O2, which otherwise is thermodynamically impossible

Which of the following statements related to Cytochrome c is wrong? A: It has a standard redox potential lower than Cytochrome a3 B: Binds one electron and becomes oxidized C: Participates in redox processes by transferring one electron D: Connects protein complexes III and IV in respiratory chain

A: It has a standard redox potential lower than Cytochrome a3

Choose the wrong statement concerning chemioosmotic mechanism for coupling of oxidation in respiratory chain and phosphorylation of ADP. A: The main protein complexes of respiratory chain in mitochondria carry out pumping H+ from the matrix into intermembrane space. B: The transmembrane pH gradient in mitochondria may be reduced and annulled by DNP (2,4- dinitrophenol), which brings protons across the inner membrane C. The pH within the mitochondrial matrix is lower than in the intermembrane space of mitochondria. D: The energy of the electrochemical H+ gradient across the inner mitochondrial membrane is the one that drives the synthesis of ATP

C. The pH within the mitochondrial matrix is lower than in the intermembrane space of mitochondria.

Which of the following statements is wrong? A: The change of the free energy that is released as a result of the hydrolysis of 1 mol ATP to 1 mol ADP and 1 mol inorganic phosphate (Pi) is 30.5 kJ (7 kkal). B: Thermodynamically unfavorable reactions (endergonic) may occur due to conjugation with thermodynamically favorable (exergonic) reactions C: In equilibrium free energy change G is always <0 D: The total change of free energy of chemically coupled processes is equal to the sum of the changes of the free energy of each of the reactions.

C: In equilibrium free energy change G is always <0

Free oxidation is important for some of the processes listed below. Which are they? 1) thermogenesis 2) synthesis of steroid hormones 3) metabolism of xenobiotics 4) metabolism of aromatic amino acids А: 1+2+3 B: 1+3 C: 2+4 D: all four

B: 1+3

Which of the following characteristics and functions are not specific for ubiquinone (coenzyme Q)? A collector of reducing equivalents B. uncoupling of oxidative phosphorylation in the respiratory chain C. transfer of H+ in membranes - mitochondrial, lysosomal, plasma membrame D. antioxidant role

B. uncoupling of oxidative phosphorylation in the respiratory chain

The following features are characteristical of the brown adipose tissue. The exception is one of them. Which is that? A. The tissue is highly vascularized. B. There is high activity of ATP-synthase C. The adipocytes are small, polygonal and have many mitochondria with a large amount of cytochromes D. In inner mitochondrial membrane a protein called termogenin is localized which has a role of proton channel.

B. There is high activity of ATP-synthase

The Fo-F1 complex in mitochondria is important for one of the following processes. Which is that? А: Oxidation of NAD.Н to NAD+ B: Obtaining of ATP from AMP and Pi C: Transport of Н+ out of the mitochondria D: Obtaining of ATP from AMD and Pi

D: Obtaining of ATP from AMD and Pi

Which of the following statements is true? A: In respiratory chain Cytochrome c can transfer simultaneously 2 electrons B: The compound, 2,4-dinitrophenol, uncouples the oxidative phosphorylation by annulling the H+ gradient on both sites of the inner mitochondrial membrane C: CN- inhibit Cytochrome c. D: The chemical substances, rotenol and amitalat, specifically inhibit cytochrome oxidase

C: CN- inhibit Cytochrome c.

Which of the following statements is true for chemiosmotic hypothesis of Mitchell? A: There is chemical conjugation (coupling) of oxidation of NAD.H with ATP synthesis B: There is synthesis of ATP during the flow of H+ along their concentration gradient across the inner mitochondrial membrane to the matrix C: There is formation of macroergic intermediate compound during transmission of eletrons D: There is generation of pH gradient on both sides of the outer mitochondrial membrane

B: There is synthesis of ATP during the flow of H+ along their concentration gradient across the inner mitochondrial membrane to the matrix

Which of the following compounds contain macroergic bonds and are macroergic? 1: enolphosphate 2: succinyl-CoA 3: 1,3- bisphosphoglycerate 4: AMP a: 1+2+3 b: 1+3 c: 2+4 d: all four

d: all four

The free energy obtained in respiratory chain can be used in mitochondria for one of the following processes. А: generation of heath B: transport of ions C: ATP synthesis D: all of the above

C: ATP synthesis

Which of the following statements concerning the synthesis of ATP in the mitochondria is not true? A: ATP-synthase is oligomeric protein comprising 3 domains - transmembrane, intramatrix and associated domains B: ATP synthase has oligomycin binding site C: ATP-synthase is inhibited directly from CN- D: ATP synthase catalyses the phosphorylation of ADP when H+ flows through the complex from intermembrane space to the the mitochondria

C: ATP-synthase is inhibited directly from CN-

Which of the following statements related to Cytochrom c is wrong? A: It is the only electron-transport protein that can be physically separated from the inner mitochondrial membrane B: It has a standard redox potential lower than Cytochrom a3 C: Participates in the process of apoptosis D: Connect protein complex II and III of respiratory chain

D: Connect protein complex II and III of respiratory chain

Which of the following processes are involved in the process of heat production in cold weather effects? 1) There is stimulation of the synthesis and secretion of thyroid hormones and noradrenaline 2) There is stimulation of lipolysis in adipose tissue 3) There is activation of adenylate cyclase, protein kinase A and hormone-sensitive lipase 4) There is coupling of the cellular respiration and oxidative phosphorylation А: 1+2+3 B: 1+3 C: 2+4 D: all four

А: 1+2+3

Which of the following enzymes, involved in the breakdown of carbohydrates in the digestive tract of humans, has/have small intestine origin? 1) sucrase 2) glucoamylase 3) lactase 4) α- amylase a)1+2+3 b)1+3 c)2+4 D) 4

b)1+3

The absorption of glucose through the mucous membrane of enterocytes in the human is performed via one of the listed types of transport proteins. Which is that? a) glucose transporter type 2 (GLUT2) b) glucose transporter type 5 (GLUT5) c) Na-dependent glucose transporter (SGLT1) d) glucose transporter type 1 (GLUT1)

c) Na-dependent glucose transporter (SGLT1)

Which of the following co-enzymes does not participate in the pyruvate dehydrogenase complex: a) pyridoxalphosphate b) thiamine pyrophosphate c) coenzyme-A d) lipoic acid

a) pyridoxalphosphate

Which of the following enzymes involved in the glycolysis is the major regulatory enzyme of this pathway: a) Phosphofructokinase-2 (PFK-2) b) Aldolase c) Phosphoglycerate kinase d) Phosphofructokinase-1 (PFK-1)

a) Phosphofructokinase-2 (PFK-2)

Which of the following metabolites is not an allosteric modulator of the main regulatory enzyme of glycolysis: a) ATP b) Glucose-6-phosphate c) AMP d) Fructose-2,6-bisphosphate

b) Glucose-6-phosphate

In which of the following cells the anaerobic glycolysis is performed: 1) white muscle fibers (during active contraction) 2) cells of the renal medulla 3) erythrocytes 4) cells of the eye lens a) 1+2+3 b) 1+3 c) 2+4 d) 1+2+3+4

b) 1+3

Which of the following substances is a direct product of the action of the enzyme glycogen phosphorylase (glycogenolysis): a) Glucose-6-phosphate b) Glucose c) Glucose-1-phosphate d) None of the mentioned above

c) Glucose-1-phosphate

Which of the following enzyme catalyzes the conversion of glucose to glucose-6-phosphate in muscle cells: a) Glucose-6-phosphatase b) Glucokinase c) Phosphoglucomutase d) Hexokinase

d) Hexokinase

Which of the following enzymes uses NAD.H as coenzyme in reduction process in anaerobic glycolysis: a) Pyruvate kinase b) Enolase c) Lactate dehydrogenase d) Glyceraldehyde-3-phosphate dehydrogenase

c) Lactate dehydrogenase

Which of the following statements about the malate-aspartate shuttle is not true: a) The shuttle is bidirectional b) Cytoplasmic and mitochondrial malate dehydrogenases participate in the shuttle c) The oxidation in the respiratory chain of the two pairs of reducing equivalents transferred by the shuttle mechanism, leads to the synthesis of 4 ATP molecules d) The pair of substrates involved in the shuttle are oxaloacetate and malate

c) The oxidation in the respiratory chain of the two pairs of reducing equivalents transferred by the shuttle mechanism, leads to the synthesis of 4 ATP molecules

Select the correct answer of the question: In how many ATP molecules the energy released from the anaerobic glycolysis is accumulated? a) Two b) Eight c) Thirty six d) Four

a) Two

Which of the following enzymes are involved in the first, non-oxidizing phase of the glycolytic pathway? 1) phosphohexosoisomerase 2) phosphofructokinase 1 3) hexokinase 4) enolase a) 1+2+3 b) 1+3 c) 2+4 d) All of the mentioned above

a) 1+2+3

Which of the following enzymes catalyzes the synthesis of fructose-2,6-bisphosphate, appearing as the strongest activator of the regulatory enzyme of glycolysis: a) Hexokinase b) Phosphofructokinase 2 c) Phosphoglycerate kinase d) Phosphofructokinase 1

b) Phosphofructokinase 2

Which of the following metabolic pathways of glucose supplies reducing equivalents for the synthesis of fatty acids, cholesterol and other reductive processes. a) Glycolysis b) Gluconeogenesis c) Pentose phosphate pathway d) Oxidative decarboxylation of pyruvate

c) Pentose phosphate pathway

Which of the following hormones has an effect on the liver cells, resulting in the formation of active dephosphorylated kinase form of the enzyme phosphofructokinase 2: a) Glucagon b) Adrenaline c) Insulin d) None of the mentioned above

c) Insulin

Which of the following enzymes of the glycolytic pathway catalyzes the step, which is a oxidative phosphorylation at the substrate level, ie carries out the synthesis of ATP when a metabolite is oxidized: a) Phosphofructokinase 1 b) Hexokinase c) Pyruvate kinase d) Phosphoglucomutase

c) Pyruvate kinase

Which of the listed deficiencies (of enzymes and/or vitamins) lead to lactic acidosis? 1) thiamine 2) erythrocyte enzymes of glycolysis 3) enzymes of pyruvate dehydrogenase complex 4) muscle enzymes of glycolysis a) 1+2+3 b) 1+3 c) 2+4 d) All of the mentioned above

d) All of the mentioned above

Which of the following statements about the pentose phosphate pathway of glucose is wrong: a) It is performed actively in skeletal muscle b) Supplies NADPH for fatty acid, cholesterol biosynthesis etc.. c) The acyl-CoA derivatives inhibit the regulatory enzyme d) In the first (oxidation) step of the process 2 molecules NADPH are obtained

c) The acyl-CoA derivatives inhibit the regulatory

The risk of hemolytic anemia is associated with the deficiency of one of the following enzymes of the pentose-phosphate pathway. Which is that enzyme? a) Transketolase b) Phosphogluconolaktonase c) Glucose-6-phosphate dehydrogenase d) Transaldolase

c) Glucose-6-phosphate dehydrogenase

Which of the following enzymes of the glycolytic pathway is regulated by a covalent modification: a) Pyruvate kinase b) Phosphofructokinase 1 c) Aldolase d) Phosphoglucomutase

a) Pyruvate kinase

The failure of which of these enzymes involved in the catabolism of fructose results into the hereditary disease "congenital fructose intolerance": a) Fructokinase b) Aldolase B c) Ttriosokinase d) none of the above mentioned

b) Aldolase B

Which of the following enzymes of gluconeogenesis does not use energy of ATP, but of GTP. a) pyruvate carboxylase b) phosphoglycerate kinase c) glucose-6-phosphatase d) phosphoenolpyruvate-carboxykinase (PEPKK)

d) phosphoenolpyruvate-carboxykinase (PEPKK)

Which of the following co-enzymes serve as such of the enzyme of the pentose phosphate pathway, transketolase, and by measuring the enzymatic activity of transketolase is diagnosed a possible deficiency of this vitamin in the body: a) pyridoxal phosphate b) thiamine pyrophosphate c) NADP d) FAD

b) thiamine pyrophosphate

In which of the following types of cells the transport of glucose is insulin-independent: 1) adipocytes 2) brain 3) skeletal muscle cells 4) erythrocytes a) 1+2+3 b) 1+3 c) 2+4 d) None of the above mentioned

c) 2+4

Which of the following statements about the pentose phosphate pathway in mature erythrocytes is true: a) Provides ribose-5-phosphate for the synthesis of nucleotides b) Provides NADPH for fatty acid synthesis c) Provides NADPH for maintaining the level of reduced glutathione, necessary for the disposal of Н2О2 d) Provides NADPH of cholesterol synthesis

c) Provides NADPH for maintaining the level of reduced glutathione, necessary for the disposal of Н2О2

Which of the following metabolites serve as substrates for the synthesis of glucose in the gluconeogenesis: 1) pyruvate 2) oxaloacetate 3) glycerol 4) acetyl-CoA a) 1+2+3 b) 1+3 c) 2+4 d) All of the above mentioned

a) 1+2+3

Which of the following statements about the transport of glucose from the blood into the cells of skeletal muscle is wrong: a) the transport is carried out by a glucose transporter (facilitated diffusion) b) insulin stimulates glucose transport through the export of glucose carriers on the cell membrane, i.e. by increasing the number of transporters on the cell membrane c) the glucose enters the cells of the skeletal muscle along the concentration gradient d) Insulin induces the biosynthesis of an enzyme which catalyzes phosphorylation of the free glucose to glucose-6-phosphate

c) the glucose enters the cells of the skeletal muscle along the concentration gradient

Which of the following enzymes involved in gluconeogenesis, is the most important regulatory enzyme in the process, subjected to allosteric regulation of variety of modulators: a) pyruvate carboxylase b) glucose-6-phosphatase c) fructose-1,6-bisphosphatase d) phosphoenolpyruvate-carboxykinase (PEPKK)

c) fructose-1,6-bisphosphatase

Which of the following hormones stimulates the gluconeogenesis by inducing biosynthesis of phosphoenolpyruvate-carboxykinase (PEPKK) and other specific enzymes of gluconeogenesis: a) Cortisol b) Insulin c) Aldosterone d) Adenocorticotropic hormone (ACTH)

a) Cortisol

Which of the following metabolites of the citrate cycle can be directly converted to phosphoenolpyruvate, and thus be incorporated into the gluconeogenesis: a) Citrate b) Oxaloacetate c) α– -Ketoglutarate d) Fumarate

b) Oxaloacetate

Which of the following enzymes involved in the catabolism of galactose catalyze the metabolic step of the conversion of galactose to galactose- 1-phosphate a) Galactose-1-phosphate uridyltransferase b) UDF- galactose-4-epimerase c) Galactokinase d) Phosphoglucomutase

c) Galactokinase

Which of the following enzymes functioning in gluconeogenesis, is allosterically activated by Acetyl-CoA: a) Glucose-6-phosphatase b) Fructose-1,6-bisphosphatase c) Phosphoenolpyruvate-carboxykinase (PEPKK) d) Pyruvate carboxylase

d) Pyruvate carboxylase

Which of the activated forms of glucose is used as a direct substrate for the synthesis of glycogen: a) Glucose-6-phosphate b) Glucose-1-phosphate c) UDP-glucose d) None of the above mentioned

c) UDP-glucose

Which of these metabolites is the allosteric activator of phosphorylated glycogen synthase b: a) АTP b) АМP c) glucose-6-phosphate d) fructose-2,6-bisphosphate

c) glucose-6-phosphate

Which of the following statements about the metabolism of liver glycogen is true: a) During its degradation lactate is released in the blood b) Glucagon stimulates its synthesis c) It is broken down during the periods of fasting d) adrenaline stimulates its synthesis

c) It is broken down during the periods of fasting

Glycerol is a non-carbohydrate precursor for the synthesis of glucose in gluconeogenesis. To which of the listed metabolites of gluconeogenesis turns the glycerol to: a) Pyruvate b) Dihydroxyacetone phosphate c) Phosphonenolpyruvate d) Fructose-6-phosphate

b) Dihydroxyacetone phosphate

Which of the following metabolic steps of gluconeogenesis is common for glycolysis and gluconeogenesis: a) fructose-6-phosphate → Glucose-6-phosphate b) pyruvate →oxaloacetate c) fructose-1,6-bisphosphate → fructose-6-phosphate d) oxaloacetate → phosphonenolpyruvate

b) pyruvate →oxaloacetate

In which of the following organs the gluconeogenesis is performed: 1) liver 2) small intestine 3) renal cortex 4) skeletal muscles a) 1+2+3 b) 1+3 c) 2+4 d) All of the above mentioned

b) 1+3

Alcohol (ethanol) inhibits the gluconeogenesis. Which of the following statements about the inhibitory effect of ethanol is wrong: a) oxidation of the ethanol leads to an increased level of NAD.H in hepatocytes b) the high levels of NAD.H direct the lactate dehydrogenase reaction to the conversion of pyruvate to lactate, which lowers the concentration of pyruvate as a precursor of gluconeogenesis. c) ethanol itself serves as inhibitor of the enzymes involved in gluconeogenesis. d) ethanol decreases the concentration of other substrates for gluconeogenesis, in pyruvate (e.g., oxaloacetate)

d) ethanol decreases the concentration of other substrates for gluconeogenesis, in pyruvate (e.g., oxaloacetate)

Which of the following statements about the effects of cortisol on the blood glucose level is correct: a) cortisol increases blood glucose level by stimulating the glycogenolysis b) cortisol increases blood glucose level by stimulating gluconeogenesis c) cortisol decreases blood glucose level by increasing the uptake of glucose into cells d) cortisol decreases blood glucose level by stimulating the glycolysis

b) cortisol increases blood glucose level by stimulating gluconeogenesis

Which of the following enzymes involved in glycogen metabolism, catalyzes the phosphorolytic breakdown of α-1,4-glycosidic bond: a) glycogen synthase b) glycogen phosphorylase c) phosphoglucomutase d) amylo-1,4 → 1,6-transglycosylase

b) glycogen phosphorylase

Which of the following statements about the metabolism of liver glycogen is wrong: a) it is synthesized after carbohydrate-rich food intake b) insulin stimulates its synthesis c) it is broken down in conditions with high blood glucose levels d) by degradation it provides blood glucose

c) it is broken down in conditions with high blood glucose levels

Which of the following statements about the influence of insulin on blood glucose level is wrong: a) Insulin reduces the level of blood glucose by accelerating its transport from the blood into insulin-dependent tissues b) Insulin stimulates the synthesis of liver and muscle glycogen c) Insulin does not stimulate glucose transport in adipose tissue d) Insulin stimulates glycolysis in the liver

c) Insulin does not stimulate glucose transport in adipose tissue

Which of the following enzymes is not present in the muscles that could explain the fact that skeletal muscles do not release blood glucose after the breakdown of glycogen: a) kinase of phosphorylase b) phosphoglucomutase c) glucose-6-phosphatase d) glycogen phosphorylase

c) glucose-6-phosphatase

The following enzymes and hormones are involved in the cascade of events leading to degradation of muscle glycogen under stress. Indicate which of them does not participate: a) Adrenaline b) Adenylyl cyclase c) Protein kinase A d) Glucagon

a) Adrenaline

Which of the following hormones is a major regulator of blood glucose level after meals: a) glucagon b) insulin c) adrenaline d) cortisol

b) insulin

Which of the following symptoms is not typical for patients with diabetes: a) glucosuria b) ketoacidosis c) hypoglycemia d) polyuria

d) polyuria

The breakdown of liver glycogen is stimulated by glucagon via one of the listed below secondary cell messengers. Which is that messenger? a) calcium ions b) cAMP c) diacylglycerol d) inositol-triphosphate

b) cAMP

Which of the following statements about the mechanism by which insulin affects the activity of glycogen synthase (regulatory enzyme of glycogenogenesis) is wrong: a) insulin decreases the level of cAMP, which leads to dropout of the activation of Protein kinase A, catalyzing the formation of the active phosphorylated form of the protein, called "inhibitor-1" b) When the inhibitory protein-1 is inactive (dephosphorylated) it does not inhibit the activity of proteinphosphstase – 1 c) the active protein phosphatase-1 catalyzes the dephosphorylation of glycogen synthase (glycogen synthase a) d) insulin signaling leads to creating of the phosphorylated form of glycogen synthase (glycogen synthase b)

a) insulin decreases the level of cAMP, which leads to dropout of the activation of Protein kinase A, catalyzing the formation of the active phosphorylated form of the protein, called "inhibitor-1"

Which of the following amino acids contains a hydroxyl group in its side chain: 1) methionine 2) threonine 3) valine 4) serine a) 1+2+3 b) 1+3 c) 2+4 d) 4

c) 2+4

Which of the following amino acids contains an aromatic ring in its side chain: 1) isoleucine 2) proline 3) serine 4) tyrosine a) 1+2+3 b) 1+3 c) 2+4 d) 4

d) 4

* What is the electric charge of an amino acid in its isoelectric point: a)positive *b) zero *c) negative *d) -2

*b) zero

* Which of the following amino acid residues in the protein molecules may participate in the formation of * ionic bonds: 1) glutamate * 2) histidine 3) arginine 4) asparagine * a) 1+2+3 * b) 1+3 c) 2+4 d) 1+2+3+4

a) 1+2+3

* Which of the following values of the pH corresponds to the isoelectric point of the amino acid alanine, keeping in mind that pKa1 of the COOH group is 2.35 and pKa2 of the NH2 group is 9.69: * a) 4.8 b) 7.24 c) 6.02 d) 3.0

c) 6.02

Which of the following amino acids has branched side chain: * a) isoleucine * b) tyrosine c) serine d) proline

a) isoleucine

* Which of the following amino acids is basic: a) glutamate * b) arginine * c) methionine * d) alanine

b) arginine

Which of the following amino acids are essential: * 1) valine 2) lysine 3) threonine 4) phenylalanine * a) 1+2+3 b) 1+3 * c) 2+4 * d) 1+2+3+4

* d) 1+2+3+4

Which chemical bonds participating in the building of protein molecules are covalent: * a) hydrogen b) ionic c) hydrophobic interactions d) disulphide bond

d) disulphide bond

Which of the following biologically active peptides is / are tissue hormone/s of gastrointestinal tract: * 1) vasopressin * 2) cholecystokinin * 3) angiotensin 4) gastrin * a) 1+2+3 * b) 1+3 c) 2+4 * d) 4

c) 2+4

Select the biologically active peptide which acts as a protector against the harmful effect of reactive oxygen species (ROS): * a) endorphin * b) glutathione * c) enkephalin * d) melanocyte-stimulating hormone

b) glutathione

Which of the following amino acids is sulfur-containing: a) isoleucine b) tyrosine c) serine d) methionine

d) methionine

Which of the following biologically active peptides is neuropeptide that binds to opioid receptors in the brain and appears to be one of the natural pain relieving substances: * a) endorphine * b) glutathione * c) neuropeptide Y * d) melanocyte-stimulating hormone

a) endorphine

Which of the following statements about biologically active peptide glutathione is wrong: a) all peptide bonds in the glutathione are formed between –COOH group bound to α-C atom of one of the amino acid and the -NH2 group of the next amino acid * b) glutathione is a tripeptide * c) sulfhydryl group of the cysteine residue has a major role in the function of glutathione * d) glutathione consists of glutamic acid, cysteine and glycine

a) all peptide bonds in the glutathione are formed between –COOH

Whichof the following biologically active peptides is a hormone with powerful vasoconstrictor effect and is involved in the regulation of Na ions in the body: * a) cholecystokinin * b) bradykinin * c) melanocyte-stimulating hormone * d) angiotensin II

d) angiotensin II

Select the chemical bonds involved in the formation of the secondary structure of the protein molecules “β-sheet”: * a) intrachain and / or interchain hydrogen bonds between amino acid side radicals * b) intrachain and / or interchain hydrogen bonds between groups of the peptide bonds * c) ionic bond * d) disulphide bonds

* b) intrachain and / or interchain hydrogen bonds between groups of the peptide bonds

* Which of the following proteins do not belong to the group of metalloproteins: * a) transferrin * b) transcortin * c) ferritin * d) ceruloplasmin

* b) transcortin

Which of the following plasma proteins does not perform transport function: * 1) α1-fetoprotein * 2) hemopexin * 3) C-reactive protein * 4) ceruloploasmin a) 1+2+3 * b) 1+3 * c) 2+4 * d) 4

* b) 1+3

* Which of the following proteins is not structural: * a) casein * b) keratin * c) fibrillin * d) elastin

* a) casein

Select the chemical bonds involved in the formation of the secondary structure of the protein molecules "α-helix": a) interchain hydrogen bonds between amino acid side radicals b) ionic bonds c) interchain hydrogen bonds between groups of the peptide bonds d) disulfide bridge

a) interchain hydrogen bonds between amino acid side radicals

* Which of the following proteins are not complex (proteides): a) Lipoproteins b) Albumin c) Nucleoproteins d) Hemoproteins

b) Albumin

* Which is the non-protein component of the complex protein, casein: a) Porphyrin structure b) Phophoric acid c) Nucleic acid d) Lipid structure

d) Lipid structure

What type of biomolecules are the enzymes by their chemical nature: * a) nucleoproteins * b) lipoproteins c) glycolipids d) proteins

d) proteins

Which of the following statements about enzymes is wrong: a) enzymes are biocatalysts b) accelerate only thermodynamically possible reactions c) withdraw the balance of the chemical reaction to produce more product compared to the uncatalyzed reaction d) they cause a decrease in the energy barrier of the chemical reaction

d) they cause a decrease in the energy barrier of the chemical reaction

Which of the compounds listed below is/are not cofactor/s of oxidoreductases? 1) NAD+ 2)FAD* 3)lipoate 4)pyridoxal phosphate  a) 1+2+3  b) 1+3  c)2+4  d) 4

d) 4

Which of the following statements about the role of the metal ions in the enzymatic catalysis are true: 1) connecting with the apoenzyme they can stabilize the conformation of the active site 2)some of them participate in the electron transfer  3)by forming a complex with the substrate they can facilitate the binding to the active site 4)do not act as catalytic groups in the active site  a)1+2+3  b)1+3  c)2+4  d)1+2+3+4

 a)1+2+3 

What is the specific name of the enzymes which catalyze the transfer of phosphate groups from ATP on substrates: * a) kinases * b) phosphatases c) oxidases d) dehydrogenases

* a) kinases

To which of the following classes of the enzymes belong peptidases? * a) hydrolases * b) transferases c) oxido-reductases * d) isomerases

a) hydrolases

To which of the following classes of the enzymes belong carboxylases? a) hydrolases b) ligases c) Isomerases d) Oxido-reductases

b) ligases

Which of the following statements about isoenzymes is wrong? a)the isoenzyme forms of an enzyme are found in all individuals of the human population b)the isoenzymes of a particular enzyme are localized in different subcellular structures, organs and tissues of one organism C)the isoenzymes catalyze different chemical reactions d)the isoenzymes differ in their physicochemical characteristics

C)the isoenzymes catalyze different chemical reactions

which type of reversible inhibitors of the enzymes may be referred antimetabolites: a)competitive b)non-competitive c)uncompetitive d)allosteric

a)competitive

Which of the following statements about the substances modulating the catalytic activity of allosteric enzymes is wrong:  a)modulators might be metabolites of the pathway in which acts the allosteric enzyme or metabolites of other metabolic pathways  b)the final product of the pathway that results in excessive concentrations is often an inhibitor of the regulatory allosteric enzyme of the same pathway  c)the action of the metabolites as modulators depends on their concentration in the cell  d)when the substrate of the metabolic pathway is in excess it always acts as an activator of the allosteric regulatory enzyme in the same pathway

d)when the substrate of the metabolic pathway is in excess it always acts as an activator of the allosteric regulatory enzyme in the same pathway

Which of the following effects on the enzymes is considered to be irreversible inhibition: 1. permanent binding and blocking of the functional group in the active site 2. destroying the native structure of the enzyme under the action of chemical agents 3. permanent binding and blocking the enzyme cofactor 4. binding with the active center by structural analogy with the substrate a) 1+2+3 b) 1+3 c)2+4 d)1+2+3+4

b) 1+3

Which of the following statements about the impact of the catalytic activity of regulatory enzymes by covalent modification (phosphorylation / dephosphorylation) is wrong: a) phosphorylation represents binding by covalent bond of the phosphate group, donor of which is ATP, to a specific functional group of an amino acid residue of the apoenzyme b)the functional group which binds the phosphate group from ATP is an amino group, not involved in the formation of the peptide bond c) phosphorylation is catalyzed by protein kinases d)in dephosphorylation which is catalyzed by protein phosphatases, the covalent bond between the phosphate group and a functional group of apoenzyme is hydrolyzed while giving inorganic phosphate

b)the functional group which binds the phosphate group from ATP is an amino group, not involved in the formation of the peptide bond

Which of the following statements about alloenzymes is wrong: a) many of the enzymes have alloenzyme forms b)alloenzymes are encoded by different alleles of the same gene c)most of the alloenzymes differ by one or several amino acid residues d)each individual of the human population has several forms of a alloenzymes of an enzyme

d)each individual of the human population has several forms of a alloenzymes of an enzyme

Bearing in mind that organophosphate compounds (e.g. the chemical weapons - sarin, soman, tabun) are irreversible inhibitors of enzymes, indicate which of the following amino acid functional groups in the active site of the enzymes are blocked by covalent bonds by those enzyme toxins: a)carboxyl group of glutamate b)ammo group of lyrine c)hydroxyl group of serine d)sulfhydryl group of cysteine

c)hydroxyl group of serine

Which of the enzymes are studied in the diagnosis of liver diseases (e.g. viral hepatitis, obstructive jaundice etc) 1. Acidic phosphatase 2. AsAT (GOT) 3. Creatine kinase 4) ALAT (GPT)  a) 1+2+3  b) 1+3  c) 2+4  d) 1+2+3+4

 c) 2+4

Tetrahydrofolate is a co-factor of transferases which catalyze the transfer of some of the listed below functional groups. Which are those groups? a)one-carbon groups b)amino groups c)phosphate groups d)reducing equivalints (H2)

a)one-carbon groups

Which of the enzymes are studied in the diagnosis of myocardial infarction: 1. AsAT (GOT) - aspartate aminotransferase 2. LDH - lactate dehydrogenase 3. CK - creatine kinase 4)HBDH - alpha-hydroxybutyrate dehydrogenase a) 1+2+3 b)1+3 c)2+4 d) 1+2+3+4

d) 1+2+3+4

Which of the following statements about allosteric enzymes is wrong? A)generally they are oligomeric proteins, i.e. they have quaternary structure b) the substrate is always allosteric activator c)contain one or more allosteric sites which bind the modulator/modulators d)the binding of the modulator is reversible

b) the substrate is always allosteric activator

Enzymes of which group catalyse synthetic reactions requiring energy most often supplied by ATP: a) Ligases b)Oxido-reductase c) Isomerases d)lyases

a) Ligases

Which of the following diseases, caused by enzyme deficiency, are deposition diseases? 1) glycogenosis 2) tyrosinosis 3) sphingolipidoses 4) porphyrias a) 1+2+3 b) 1+3 c) 2+4 d) 1+2+3+4

b) 1+3

The symptoms of which of the following enzymopathies are due to acceleration of the minor pathways of the substrates of the main metabolic pathway having enzyme deficiency: a) fructosuria b) gout c) phenylketonuria d) porphyria

b) gout

The deficiency of which of the following vitamins causes the disease “beriberi”? * a) folic acid * b) thiamine * c) biotin * d) ascorbic acid

b) thiamine

The deficiency of which of the following vitamins causes the disease scurvy? 1. ascorbic acid 2. thiamine 3. Biotin 4. niacin

1. ascorbic acid

Which of the following vitamins is not water soluble: a) Riboflavin b) Cholecalciferol c) Biotin d) Niacin

b) Cholecalciferol

Which of the following statements about vitamin b6 is wrong: a) It exist in three natural derivatives: pyroxine (ol), pyridoxal, pyridoxamine. b) Biologically active are two of the phosophates of the two forms, as pyridoxalphosphate is main co-factor form. c) Pyridoxalphosphate is cofactor only of transaminases d) Pyridoxalphophate stabilizes and is required for activation of muscle glycogen phosphorylase

c) Pyridoxalphosphate is cofactor only of transaminases

Which of the following enzyme groups biotin (vitamin h.) is a prosthetic group? a) Transaminases b) Dehydrogenases c) Decarboxylases d) carboxylases

b) Dehydrogenases

Which of the following types of lipids is not a component of the membrane structures: * a) cholesterol * b) triacylglycerols c) cardiolipins d) phosphatidylethanolamine

b) triacylglycerols

Which of the following lipids are glycolipids: * 1) sphingomyelins 2) gangliosides 3) cephaline * 4) cerebrosides a) 1+2+3 * b) 1+3 * c) 2+4 * d) none of the above mentioned

* d) none of the above mentioned

Which of the following statements about the activation of fatty acids before their inclusion in β- oxidation is wrong: * a) activation of fatty acids is by binding their carboxyl group with coenzyme A and turning * them into acyl CoA derivatives * b) activation of the fatty acids takes place in the mitochondrial matrix * c) activation of the fatty acids takes place in the endoplasmic reticulum * d) long chain fatty acids are activated

c) activation of the fatty acids takes place in the endoplasmic reticulum

Which of the following pairs of vitamins act as coenzymes in the β- oxidation of fatty acids with an odd number of carbon atoms: * a) vit. B1 and folic acid * b) biotin and vit. B12 * c) folic acid and biotin * d) vit.В12 and vit.В1

b) biotin and vit. B12

* Which of the following shuttle mechanisms is involved in the transfer of activated fatty acids from the cytosol into the mitochondria?: * a) malate-aspartate * b) glycerol-phosphate * c) acyl-carnitine * d) none of the above mentioned

* c) acyl-carnitine

Which of the following metabolites is an allosteric inhibitor of the regulatory enzyme of β- oxidation: * a) Propionyl-CoA * b) Malonil-CоА * c) Butyryl-CoA * d) none of the above mentioned

* b) Malonil-CоА

Which of the following statements about ketone bodies is wrong: * a) substrate for the synthesis of ketone bodies is acetyl CoA, obtained from the oxidative decarboxylation of pyruvate * b) ketone bodies are acetoacetate, β-hydroxybutyrate and acetone, as acetone is product of acetoacetate degradation. * c) ketone bodies are an energy source alternative of glucose * d) the concentration of the β-hydroxybutyrate in the blood is usually higher than that of the acetoacetate

* d) the concentration of the β-hydroxybutyrate in the blood is usually higher than that of the acetoacetate

In which of the following organs the synthesis of ketone bodies (ketogenesis) takes place: * a) skeletal muscles * b) brain * c) kidneys * d) liver

* d) liver

Which of the following hormones stimulates ketogenesis in the periods of fasting: * a) insulin * b) cortisol * c) glucagon * d) none of the above mentioned

* c) glucagon

* Triacylglycerols from the diet are transported by one of the following transport form. Which is that: * a) chylomicrons * b) verylow-densitylipoproteins(VLDL) * c) high-density lipoproteins (HDL) * d) low-densitylipoproteins(LDL

* a) chylomicrons

Which of the following enzymes catalyzes the hydrolysis of triacylglycerols located in different lipoprotein complexes (e.g. in chylomicrons, VLDL) * a) lecithin-cholesterol-acyltransferase * b) lipoproteinlipase * c) pancreatic lipase * d) hormone-sensitive lipase

* b) lipoproteinlipase

Which of the following transport forms of lipids contain the so-called, alpha (α) cholesterol, which usually is determined in clinical laboratory tests of the blood. * a) chylomicrons * b) low-density lipoproteins(LDL) * c) high-density lipoproteins (HDL) * d) very low-density lipoproteins(VLDL

* c) high-density lipoproteins (HDL)

* b) lipoproteinlipase

Which of the following statements for the synthesis of saturated fatty acids with an even number of carbon atoms (palmitic acid) is false: * a) direct substrate for the synthesis is malonyl-CoA * b) NAD.H serves as a donor of reducing equivalents * c) synthesis takes place in the cytosol * d) binding of each of the two-carbon fragment in the elongation process of the carbon chain of the fatty acid is performed in four metabolic step

* d) binding of each of the two-carbon fragment in the elongation process of the carbon chain of the fatty acid is performed in four metabolic step

Which of the following enzymes involved in β-oxidation of fatty acids with an even number of carbon atoms, is a regulatory enzyme of the process: * a) carnitine acyltransferase I (carnitine:palmitoyltransferase I) * b) acyl CoA dehydrogenase * c) enoyl CoA hydrogenase * d) carnitineacyltransferaseII(carnitine:palmitoyltr

* a) carnitine acyltransferase I (carnitine:palmitoyltransferase I)

* Which of the following statements about the regulation of the activity of the regulatory enzyme of fatty acid biosynthesis, acetyl-CoA carboxylase is false: * a) the activity is regulated by the mechanism of covalent modification (phosphorylation / dephosphorylation), аs the active form is phosphorylated. * b) the activity is influenced by the action of hormones, as insulin stimulates the enzymatic activity * c) the activity is regulated by the mechanism of covalent modification (phosphorylation / dephosphorylation), the active form is dephosphorylated. * d) the activity of the enzyme is regulated allosterica

* c) the activity is regulated by the mechanism of covalent modification (phosphorylation / dephosphorylation), the active form is dephosphorylated.

Which one of the metabolites of glycolysis occurring in adipocytes, is converted to glycerol-3- phosphate being one of the substrates for the synthesis of triacylglycerols in adipose tissue: * a) glyceraldehyde-3-phosphate b) pyruvate * c) 3-phosphoglycerate * d) dihydroxyacetonephosphate

* d) dihydroxyacetonephosphate

Which of the following enzymes is regulatory in degradation of triacylglycerols in adipose tissue: * a) lipoprotein lipase * b) glycerolkinase * c) phospholipase * d) hormone-sensitive lipase

* d) hormone-sensitive lipase

Which of the following statements about the degradation of triacylglycerols in adipose tissue is false: a)triacylglycerols are degraded when the insulin/glucagon ratio in the blood is high b)triacylglycerols are degraded during fasting *c) triacylglycerols are degraded rapidly in patients with diabetes mellitus * d) triacylglycerols are degraded under elevated level

a)triacylglycerols are degraded when the insulin/glucagon ratio in the blood is high

* Which of the following biological functions of cholesterol is not correct: * a) cholesterol participates in the construction of the cell membranes as a stabilizing component * b) cholesterol serves as a precursor for steroid hormone synthesis * c) cholesterol serves as a precursor for vitamin E synthesis * d) cholesterol serves as a precursor for bile acids synthesis

* c) cholesterol serves as a precursor for vitamin E synthesis

* Which of the following metabolites is obtained in the biosynthesis of ketone bodies, and in the biosynthesis of cholesterol in the liver, i.e., appears to be a key metabolite. * a) mevalonic acid * b) hydroxy-methylglutaryl-CoA * c) ß- hydroxybutyrate * d) isopentenylpyrophosphate

* b) hydroxy-methylglutaryl-CoA

Which of the following cofactors supplies reducing equivalents for the action of the enzyme HMG-CoA reductase: * a) NAD.H b) FAD.Н2 c) NADP.Н * d) FMN.H2

* a) NAD.H

Which of the following statements about regulation of cholesterol biosynthesis is true: * a) cholesterol synthesis is not affected by the concentration of cholesterol * b) cholesterol acts as an allosteric activator of the HMG-CoA reductase * c) cholesterol acts as an allosteric inhibitor of HMG-CoA synthase * d) cholesterol represses the synthesis of HMG-CoA reductase

* d) cholesterol represses the synthesis of HMG-CoA reductase

Which of the following statements about the regulation of enzyme activity of 7α-hydroxylase which regulates the conversion of cholesterol to bile acids in the liver is false: * a) the catalytic activity of 7α-hydroxylase is regulated by phosphorylation / * dephosphorylation, and the active form of the enzyme is dephosphorylated * b) cholesterolenhances7α-hydroxylasemRNA * c) bile acids inhibit the enzyme synthesis * d) in Vit. C deficiency the metabolic step catalyzed by 7α-hydroxylase slows down.

* a) the catalytic activity of 7α-hydroxylase is regulated by phosphorylation / * dephosphorylation, and the active form of the enzyme is dephosphorylated

* Which of the following statements about arachidonic acid is wrong: * * A) arachidonic acid is a polyunsaturated FA containing 20 carbon atoms * B) arachidonic acid is 3 polyunsaturated fatty acid * C) arachidonic acid is a precursor for the synthesis of eicosanoids: prostaglandins, thromboxanes with 2 double bonds and leukotrienes with 4 double bonds * D) arachidonic acid participates in the construction of membrane phospholipids

* B) arachidonic acid is 3 polyunsaturated fatty acid

Which of the following statements about the physiological functions of eicosanoids is false: * a) They participate in inflammatory processes, in injuries and infections * b) Some of the eicosanoids are involved in platelet aggregation * c) Some regulate smooth muscle contractions (intestine, uterus) * d) All eicosanoids act as vasoconstrictors

* d) All eicosanoids act as vasoconstrictors

* The high concentration of which of the lipid transport forms listed below decreases the risk of developing of atherosclerosis and coronary heart disease? * a) HDL * b) chylomicrons * c) LDL d) VLDL

* a) HDL

Which of the listed subcellular compartments is the place, where the oxidation of fatty acids leading to introduction of double bond is performed: * a) mitochondria * b) lysosomes * c) endoplasmic reticulum * d) cytoplasm

* c) endoplasmic reticulum

* Eicosatetraenoic acid is a precursor for the synthesis of: * 1) prostanoids with 2 double bonds 2) leukotrienes with 3 double bonds 3) lipoxins with 4 double bonds * 4) prostanoids with 3 double bonds * a) 1+2+3 b) 1+3 c) 2+4 * d) none

c) 2+4

* The oxidative phase of the PPP (pentose phosphate pathway) is important for: * 1) cholesterol synthesis * 2) synthesis of ATP 3) fatty acid synthesis * 4) gluconeogenesis * a) 1+2+3 * b) 1+3 * c) 2+4 * d) allfour

* c) 2+4

* Which of the following mechanisms, for activating of the biosynthesis of fatty acids from the insulin is incorrect: * a) insulin with its signaling cascade leads to the active unphosphorylated form of the regulatory enzyme acetyl-CoA carboxylase * b) insulin with its signaling cascade leads to induction of the biosynthesis of the regulatory enzyme of fatty acid synthesis - acetyl- CoA carboxylase * c) insulin with its signaling cascade leads to induction of the biosynthesis of the multifunctional enzyme complex, fatty acid synthase complex * d) insulin with its signaling cascade leads to activation of the enzyme glycerol-3- phosphate acyl transferase, via maintaining of its unphosphorilated form

* d) insulin with its signaling cascade leads to activation of the enzyme glycerol-3- phosphate acyl transferase, via maintaining of its unphosphorilated form

Which of the following compounds are cholesterol derivatives? 1) aldosterone 2) adrenaline 3) cortisol 4) cholicacid a) 1+2+3 b) 1+3 c) 3+4 d) 1+3+4

a) 1+2+3

Which of the following compounds is a key (a key metabolite) in the synthesis of most glycerolipids? а) choline b) CDP-choline c) phosphatidic acid d) CDP- diacylglycerol

c) phosphatidic acid

Which of the enzymes that catalyze reactions in the synthesis of glycerolipids is regulatory? a) phosphatidic acid phosphatase b) glycerol-3P-acyltransferase c) diacylglycerol acyltransferase d) phosphatidylinositol synthase

b) glycerol-3P-acyltransferase

Which of the following groups of lipids are glycolipids? 1) sphingomyelins 2) gangliosides 3) cerebrosides 4) lecithins a) 1+2+3 b) 2+3 c) 1+4 d) 2+3+4

d) 2+3+4

Which of the following essential polyunsaturated fatty acids (PUFA) are supplied only from foods of animal origin. 1) linoleicacid 2) arachidonicacid 3) eicosapentaenoic acid 4) linolenic acid a) 1+2+3 b) 2+3 c) 1+4 d) 2+3+4

b) 2+3

On which positions in the hydrocarbon chains of the fatty acids double bonds may be introduced in man (desaturases function in human cells)? а) 4, 5, 8 and 9 b) 4, 5, 6 and 9 c) 5, 8, 11 and 14 d) 4, 5, 8 and 9

d) 4, 5, 8 and 9

Which of the following biological effects are typical for PGE2? * 1) bronchoconstrictor * 2) vasodilator * 3) inhibits the secretion of gastric juice * 4) inhibits the uterine contractions * a) 1+2+3 * b) 2+3 c) 2+4 d) 2+3+4

c) 2+4

* Which of the following reactions and processes provide reducing equivalents (NADPH) used in the synthesis of fatty acids? * 1) anaerobic glycolysis 2) pentose phosphate pathway 3) reaction catalyzed by malate dehydrogenase * 4) reaction catalyzed by “malate” enzyme * a) 1+2+3 * b) 2+3 c) 2+4 * d) 2+3+4

c) 2+4

* Which of the following compounds is the direct donor of 14 of the 16 carbon atoms in the synthesis of palmitic acid? * а) acetyl-CоА b) acyl-CоА c) malonyl-CоА d) methilmalonyl-CоА

c) malonyl-CоА

Which of the following compounds are not allosteric activators of the main key enzyme in the synthesis of fatty acids, Acetyl CoA carboxylase? 1) acyl-CоА 2) acetyl-CоА 3) malonyl-CоА 4) citrate a) 1+2+3 b) 2+3 c) 2+4 d) 2+3+4

c) 2+4

In which of the following organs the synthesis of ketone bodies (ketogenesis):takes place a) skeletal muscle b) brain c) heart muscle d) liver

d) liver

Which of the following hormones stimulates ketogenesis in periods of fasting? a) insulin b) cortisol c) ACTH d) glucagon

d) glucagon

Which of the following compounds are ketone bodies with metabolic importance for tissues: * 1) acetoacetate 2) oxaloacetate 3) β- hydroxybutyrate * 4) acetone * a) 1+2+3 * b) 1+3 * c) 2+3 * d) 1+3+4

* a) 1+2+3

Which of the following lipoprotein complexes are the main carriers of TAG to peripheral tissues: 1) Chylomicrons 2) VLDL 3) LDL 4) HDL a) 1+2+3 b) 1+2 c) 1+3+4 d) 3+4

b) 1+2

Which of the following enzymes play an important role in the metabolism of lipoprotein complexes: * 1) hepaticlipase * 2) pancreaticlipase * 3) lipoprotein lipase * 4) LCAT (lecithin cholesterol acyltransferase) * a) 1+2+3 * b) 1+2 * c) 1+3+4 * d) 3+4

* d) 3+4

Which of the following lipoprotein complexes transport the "bad" cholesterol and raising of their levels is a risk factor for atherosclerosis: * а) chylomicrons * b) VLDL c) LDL d) HDL

c) LDL

Which of the following coenzymes serves as a donor of reducing equivalents in the synthesis of fatty acids in fatty acid synthase complex? * a) NAD.Н * b) FAD.Н2 * c) NADP.Н * d) FMN.Н2

* c) NADP.Н

How many turns (cycles) of the spiral of β-oxidation occur for oxidation of palmitic acid (Palmitoyl-CoA) to Acetyl-CoA? * a) 10 * b) 8 * c) 7 * d) 6

* c) 7

In which of the following cell compartments of hepatocytes the ketogenesis occurs? * * a) cytosol * b) mitochondria * c) endoplasmic reticulum * d) lysosomes

* b) mitochondria

Which of the following metabolites is a product of the degradation of ketone bodies (ketolysis) in extrahepatic tissues? * a) malonyl -CоА * b) acetyl-CоА * c) succinyl -CоА * d) propionyl-CoA

* b) acetyl-CоА

The catabolic pathways are primarily: Reductive and endergonic Endergonic and exergonic Oxidative and endergonic Oxidative and reductive Oxidative and exergonic

Oxidative and exergonic

Insulin synthesis: 1) occurs in the β-cells of the Langerhans islands, 2) is initiated at a low blood glucose, 3) occurs in the mitochondria and Golgi apparatus, 4) occurs with the release of C-peptide, 5) it is composed of 3 polypeptide chains connected by 2 disulfide bridges 1 + 4 3 + 5 2 + 5 1 + 2 2 + 3

1 + 4

Which of the following enzymes is NOT tested for myocardial infarction? ALT (GPT) creatine kinase lactate dehydrogenase alpha-hydroxybutyrate dehydrogenase AST (GOT)

ALT (GPT)

Which of the listed statements are correct? 1) pyruvate is the substrate for the synthesis of ketone bodies 2) a significant increase in the concentration of ketone bodies leads to a condition called ketoacidosis 3) ketone bodies are an alternative source of energy for the extrahepatic tissues (muscles, brain) 4) ketone bodies are the main energy source for the liver 5) after activation ketone bodies enter the glycolysis, where they are completely oxidized 3+4 1+3 2+5 2+3 1+5

2+3

b) glycerol-3P-acyltransferase

In the cells, the activated fatty acids are transported through the inner mitochondrial membrane into the matrix with the help of: carnitine carnosine carotene creatine xanthine

carnitine

Which of the following enzymes is a component of the glycerol phosphate shuttle? malate dehydrogenase triose phosphate isomerase glycerol kinase glycerol 3-phosphate dehydrogenase glyceraldehyde 3-phosphate dehydrogenase

glycerol 3-phosphate dehydrogenase

Cofactor of galactokinase is: NADH NADPH FMN ATP FAD

ATP

An example of a functional plasma enzyme is: creatine kinase aspartate aminotransferase α-amylase lactate dehydrogenase ceruloplasmin

α-amylase

Which are the enzymes that deliver NADPH for the synthesis of fatty acids and cholesterol? 1) α-ketoglutarate dehydrogenase 2) malic enzyme 3) the cytosolic isocitrate dehydrogenase 4) the mitochondrial isocitrate dehydrogenase 5) glucose-6-phosphate dehydrogenase 1+3+4 1+3+5 1+2+3 2+3+4 2+3+5

2+3+5

Which of the following are the regulatory enzymes of glycolysis? 1) hexokinase 2) 2) glyceraldehyde 3-phoshate dehydrogenase 3) triose phosphate isomerase 4) phosphofructokinase I 5) pyruvate kinase 2+4+5 1+2+3 1+4+5 2+3+4

1+4+5

Which of the listed factors are needed for activation of pancreatic lipase: 1) acidic conditions 2) chloride ions 3) neutral or weak alkaline conditions 4) bile acids and lysolecithins 5) the action of colipase 2+3+5 1+2+5 1+2+3 3+4+5 1+3+4

3+4+5

Disulfide bonds in the protein molecules are formed between: two methionine residues two cysteine residues two serine residues two glutamine residues

two cysteine residues

Collagen is characterized by the presence of: 1) hydroxyprolyl and hydroxylysyl amino acid residues 2) hydroxyprolyl, but not hydroxylysyl amino acid residues 3) carbohydrate component 4) a structure called "desmosine" 5) triple-helical structure 2+3+5 1+3+4 1+3+5 1+2+3 2+3+4

1+3+5

Which of following statements are true? 1) Macroergic compounds are a link between exergonic and endergonic processes 2) ATP contains three macroergic bonds 3) ATP contains two macroergic bonds 4) ADP contains two macroergic bonds 5) AMP contains only one macroergic bond 1+2 2+5 1+5 1+3 1+4

1+3

Sphingosine is a precursor of: 1) lecithins 2) phosphatidylinositols 3) cerebrosides 4) gangliosides 5) sphingomyelins 1+3+5 3+4+5 1+3+4 2+4+5 1+2+5

3+4+5

Which of the following proteins is an iron-storing protein? hephaestin hemosiderin transferrin ferritin ceruloplasmin

ferritin

Which of the following statements regarding the β-oxidation of fatty acids with an even number of C-atoms are correct? 1) the oxidation of fatty acids is a mitochondrial process 2)the oxidation of fatty acids is an anaerobic process 3)the end products are Acetyl-CoA, malonyl-CoA, NADH and FADH2 4) the end products are Acetyl-CoA, propionyl-CoA, NADH and FADH2 5) the end products are Acetyl-CoA, NADH and FADH2 1+5 2+5 2+4 3+4 1+3

1+5

Which of the listed molecules are oxidized in the Krebs cycle? 1) non-essential amino acids (the carbon skeleton) 2) ketone bodies 3) acetyl-CoA derived from the pyruvate dehydrogenase complex 4) propionyl-CoA obtained by the degradation of fatty acids with an odd number of carbon atoms 5) the final products of the β-oxidation 2+4+5 all of them 1+3+4 1+3+5 2+3+5

1+3+5

Which of the following enzymes are expressed only in the liver? 1) urease 2) 3-hydroxy-3-methyl-glutaryl-CoA reductase 3) carbamoyl phosphate synthetase I 4) pyruvate carboxylase 5) bilirubin UDP-glucuronyl transferase activity 4+5 2+4 3+5 1+3 1+5

4+5

Protein denaturation leads to: 1) Changes of amino acid composition of the protein molecule 2) Destroying primary structure of the protein molecule 3) Loss the biological activity of the protein 4) Increasing the chemical reactivity of the polypeptide chain of the protein 5) Destroying the secondary, tertiary and quaternary structure 2+3+4 2+3+5 3+4+5 1+3+4 1+2+3

3+4+5

The process of heat production depends on: 1) the activity of mitochondrial respiratory chains when the electron transport and phosphorylation are uncoupled 2) the short electron transport chains localized in the endoplasmic reticulum 3) the activity of lysosomal short electron transport chains 4) ion channels in the inner mitochondrial membrane when open 5) ion channels in the inner and outer mitochondrial membranes when open 1+5 2+3 3+5 2+5 1+4

1+4

Carbamoyl phosphate synthetase I, which catalyses the formation of carbamoyl phosphate in the urea cycle: 1) is located in the mitochondria of hepatocytes 2) is located in the cytoplasm of hepatocytes 3) is a regulatory enzyme 4) is allosterically activated by N-acetylglutamate 5) is allosterically activated by N-acetylglutamine 2+3+5 3+4+5 2+3+4 1+3+5 1+3+4

1+3+5

Antithrombin III: 1) participates in fibrinolysis 2) inhibits the activity of enzymes of the blood clotting process 3) is activated by urokinase 4) works in a complex with the tissue factor (factor III) 5) is activated by heparin 2+4 3+4 2+5 4+5 1+3

2+5

Which of the following enzymes catalyse reactions from pentose phosphate pathway? phospho hexose isomerase 2) glucose 6-phosphate dehydrogenase 3) transaldolase 4) transketolase 5) hexokinase 1+3+4 2+3+5 3+4+5 1+2+5 2+3+4

2+3+4

Which of the following enzymes of purine biosynthesis are allosterically regulated? 1) phosphoribosyl pyrophosphate (PRPP) synthetase 2) formyl transferase 3) glutamine-PRPP amidotransferase 4) adenylosuccinase 5) xanthine oxidase 3+4 2+5 1+3 2+4 1+5

1+5

Hemorrhages in the joints and subcutaneous tissue, formation of ulcers that are difficult to heal, softening of the gums, anemia are clinical signs of the disease: pellagra pernicious anemia scurvy beriberi gout

scurvy

Which of the following enzymes catalyze the irreversible steps in gluconeogenesis? 1) aldolase 2) glucose 6-phosphatase 3) fructose 1,6-bisphosphatase 4) pyruvate kinase 5) pyruvate carboxylase 2+3+4 1+2+3 2+3+5 3+4+5 1+3+5

2+3+5

The role of free fatty acids in the process of heat production in brown adipose tissue is: 1) isolating the internal organs of the low temperature of the environment 2) when oxidized, they supply hydrogen to the respiratory chain 3) synthesis of triacylglycerols 4) synthesis of ketone bodies 5) activate the uncoupling protein 1. 1+2 3+5 2+4 1+3 2+5

2+5

How many are the ATP molecules synthesized by the short electron transport chains during the process of microsomal oxidation? no ATP molecules two ATP molecules one ATP molecule three ATP molecules four ATP molecules

two ATP molecules

In transamination: 1) amino acids are converted to biogenic amines 2) one amino acid is converted to a keto acid and another keto acid is converted to the corresponding amino acid 3) the amino groups of amino acids are released as free ammonia 4) pyridoxal phosphate participates as a cofactor 5) tetrahydrobiopterin participates as a cofactor 2+5 1+3 2+4 3+4 1+5

2+4

In which part of the cell does the pentose phosphate pathway takes place? the cytosol the cytosol and matrix of the mitochondria the inner membrane of the mitochondria the mitochondrial matrix peroxisomes

the cytosol

Cori's cycle is about: synthesis of glutamine in the brain and its deamination in the liver synthesis of urea in the liver and its excretion with urine binding of aspartate to a metabolite and further cleavage of its carbon skeleton in the form of fumarate formation of alanine from pyruvate in the muscles and formation of glucose from alanine in the liver formation of lactate from glucose in the skeletal muscles and formation of glucose from lactate in the liver

formation of lactate from glucose in the skeletal muscles and formation of glucose from lactate in the live

Which of the following hormones are recognized and bound by intracellular receptors? 1) retinoic acid 2) triiodothyronine (T3) 3) TSH 4) calcitriol 5) serotonin 2+3+4 1+3+5 1+2+4 1+2+3 2+3+5

1+2+4

Which of the listed enzymes is an enzyme complex of the respiratory chain which does NOT pump protons into the intermembrane space? Cyt.C: oxygen oxidoreductase Cytochrome reductase Succinate dehydrogenase NAD.H: ubiquinone oxidoreductase Isocitrate dehydrogenase

Succinate dehydrogenase

Which is the mechanism involved in the regulation of the enzymes of Krebs cycle? a)allosteric control, exerted by either the substrates or products of the chemical reactions b)proteolytic “maturation” of the protein structure of the enzymes c)reversible covalent modifications, caused by hormonal signal cascades d)with the aid of additional enzymes called dprotein kinases or phosphatases changes in the intracellular location of the enzymes

a)allosteric control, exerted by either the substrates or products of the chemical reactions

Which of the end products of heme degradation are increased in parenchymal jaundice (hepatitis)? 1) urobilinogen in urine 2) bilirubin in the urine 3) indirect serum bilirubin 4) direct serum bilirubin 5) stercobillin in the stool 2+3+4 1+3+4 2+3+5 1+2+3 1+3+5

2+3+4

Which of the following reactions are reactions of the covalent modification of regulatory enzymes: 1)acetylation 2) methylation 3) phosphorylation 4) adenylation 5) uridinylation 1+3+5 2+4+5 1+2+3 all of them 1+3+4

1+2+3

Which statements about hormone-sensitive lipase are correct? 1) it is activated by insulin 2) the active form is the dephosphorylated 3) it is activated by glucagon 4) the active form is the phosphorylated 5) it hydrolyses monoacylglycerols to form free fatty acids (FFAs) and glycerol 1+5 1+3 1+2 2+4 3+4

1+5

Which of the listed compounds are known as ketone bodies? 1) oxaloacetate 2) acetone 3) acetoacetate 4) 3-hydroxybutirate 5) acetoacetyl-CoA 3+4+5 1+3+5 1+2+3 1+2+5 2+3+4

2+3+4

Which of following statements about non-competitive inhibitors are true? 1) Inhibitor is not a structural analog of the substrate 2) Inhibitor is a structural analogue of the substrate 3) Binds to groups from the active center of the enzyme 4) Binds to groups outside the active site of the enzyme 5) The inhibitory effect depends only on the concentration of the inhibitor 2+3+4 1+3+4 2+3+5 1+3+5 1+4+5

1+4+5

Respiratory chains: 1) are located in the outer mitochondrial membrane 2) are located in the inner mitochondrial membrane 3) are complex structures, assembled from enzymes, non-enzyme proteins and redox-systems (electron carriers) 4) transfer hydrogen from NADH or other substrates to oxygen as a final acceptor 5) could act under both aerobic and anaerobic conditions 1+3+4 2+3+4 1+3+5 1+4+5 2+4+5

2+3+4

Which of the following is NOT typical for adipocytes of brown adipose tissue: a large amount of cytochromes many mitochondria rich blood supply presence of thermogenic uncoupling protein high ATP synthase activity

high ATP synthase activity

Which of the following statements about NAD+ and NADP+ are true? 1) Both cofactors are derivatives of vitamin B1 (thiamine) 2) Both cofactors are derivatives of vitamin B3 (niacin, vitamin PP) 3) Both cofactors are derivatives of vitamin B6 (pyridoxol) 4) NAD+ and NADP+ participate in the processes of biological oxidation as hydrogen carriers 5) NAD+ and NADP+ are mainly cofactors of anaerobic dehydrogenases 1+3+4 3+4+5 2+4+5 2+3+5 1+4+5

2+4+5

Choose the correct statements about glycogen metabolism: 1) glycogen is synthesized and stored only in the mitochondrial matrix 2) hepatic glycogen is utilized in the maintaining of blood glucose level between the meals 3) glucose-6-phosphate produced in the muscles passes through the cell membrane along the concentration gradient to the blood 4) hepatocytes of the liver contain the enzyme glucose-6 phosphatase, which releases free glucose 5) muscle glycogen is used only by muscle cells 1+2+3 1+2+5 2+4+5 1+3+4 1+3+5

2+4+5

Which of the listed compounds are substrates of gluconeogenesis? 1) lactate 2) acetyl-CoA 3) glycerol 4) alanine, glutamate, aspartate 5) glucose 2+4+5 all of them 2+3+4 1+3+4 1+3+5

1+3+4

Glutathione is: tissue hormone natural opiate a natural antioxidant a steroid compound

a natural antioxidant

Which of the following metabolic disorders ARE NOT observed in diabetes type 2? 1) hyperglycemia 2) ketoacidosis 3) hypertriglyceridemia (elevated levels of VLDL) 4) hyperchylomicronemia 5) glucosuria 1+5 3+4 2+4 1+3 2+5

2+4

Which of the biosynthetic processes are carried out with the participation of tetrahydrofolic acid derivatives as cofactors: 1) synthesis of purines (С2 and С8 atoms) 2) synthesis of choline from ethanolamine 3) synthesis of methionine from homocysteine 4) synthesis of creatine phosphate 5) synthesis of TMP from dUMP 1+3+5 2+3+5 1+2+3 3+4+5 2+3+4

1+3+5

Choose the correct statements about the role of glycolysis in the body: 1) delivers reducing equivalents for anabolic pathways 2) supplies acetyl-CoA for the synthesis of ketone bodies 3) supplies substrates for the synthesis of essential amino acids 4) delivers energy to muscle cells during prolonged starvation 5) supplies acetyl-CoA for fatty acid synthesis 2+4+5 1+2+3 1+3 3+5 2+4

2+4

cAMP-dependent protein kinase (PKA) phosphorylates: 1) glycogen synthase and inactivates it 2) glycogen synthase and activates it 3) glycogen phosphorylase kinase and activates it 4) glycogen phosphorylase kinase and inactivates it 5) glycogen phosphorylase and activates it 2+5 2+4 1+5 1+3 3+4

1+5

Which of the following enzymes are components of the pyruvate dehydrogenase complex (PDH)? 1)acetyl-CoA carboxylase 2) pyruvate dehydrogenase 3) dihydrolipoyl transacetylase 4) dihydrolipoyl dehydrogenase 5) pyruvate kinase 3+4+5 1+3+4 1+2+4 2+4+5 2+3+4

2+3+4

The unit of enzyme quantity (activity) in the International System of Units (SI) is Katal. One Katal (Kat) is the amount of the enzyme required to convert: One mole of substrate for one second One milimole of substrate per one minute one milliliter of substrate per one minute One micromole of substrate per one minute One micromole of substrate for one second

One mole of substrate for one second

Indicate the correct combinations of a neuromediator and the amino acid, form which it is synthesized. 1) gamma-aminobutirate from aspartate 2) gamma-aminobutirate from glutamate 3) serotonin from tryptophan 4) serotonin from tyrosine 5) dopamin from tyrosine 3+4+5 1+3+5 1+2+3 2+3+4 2+3+5

2+3+5

Which of the following statements about cholesterol are true? 1) it is synthesized from acetyl-CoA 2) it's synthesis occurs in the cytosol and in the endoplasmic reticulum 3) the main regulatory enzyme of cholesterol synthesis is HMG-CoA synthase 4) it is fully degraded in the liver 5) it's synthesis is stimulated by insulin 1+3+4 1+2+5 1+3+5 2+4+5 3+4+5

1+3+5

Which of the processes are specific to the liver only? 1) conversion of indirect bilirubin to direct bilirubin, 2) urea cycle, 3) glycogen synthesis, 4) cholesterol synthesis, 5) gluconeogenesis 3 + 5 1 + 2 4 + 5 2 + 3 1 + 4

1 + 2

Which statements about thyroid hormones (T4 and T3) are true? 1) inhibit gluconeogenesis and glycogenolysis to prevent the formation of free glucose, 2) T3 is formed only in the thyroid gland, 3) T4 and T3 increase the synthesis and secretion of TSH, 4) T4 and T3 decrease the synthesis and secretion of TSH, 5) the enzyme thyroid peroxidase is involved in their synthesis 2 + 3 1 + 4 3 + 5 1 + 2 4 + 5

4 + 5

Which is the WRONG statement? a)VLDL transports triacylglycerols from the liver to the extrahepatic tissues b)LDL contains only apo B-100 c) VLDL is metabolized to LDL after hydrolysis of triacylglycerols by hormone-sensitive lipase d)the main components of LDL are cholesterol and cholesteryl esters chylomicrons transport mainly triacylglycerols from the intestines to the liver and other tissues

a)VLDL transports triacylglycerols from the liver to the extrahepatic tissues

Gout could be caused by: a)complete deficiency of hypoxanthine/guanine phosphoribosyl transferase b)a partial deficiency of xanthine oxidase c)a partial deficiency of hypoxanthine/guanine phosphoribosyl transferase d)abnormally increased activity of aspartate transcarbamoylase deficiency of folic aci

complete deficiency of hypoxanthine/guanine phosphoribosyl transferase

Which of the listed molecules are signaling molecules? 1) interleukins 2)acetylcholine 3) interferons 4) prostaglandins 5) leukotrienes c) 2+4+5 d) 1+4+5 b) 1+3+4 all of them a) 1+2+3

all of them

What is the fate of hydrogen released in oxidative reaction in glycolysis? 1) used for the synthesis of fatty acids 2) under anaerobic conditions it is directed for pyruvate reduction 3) under aerobic conditions it is directed for pyruvate reduction 4) under aerobic conditions it is transferred to the matrix of mitochondria 5) directed for the reduction processes in the synthesis of cholesterol 2+4+5 1+3 2+4 3+5 1+2+3

2+4

Which of the following symptoms is not typical for patients with diabetes: hypoglycemia ketoacidosis polyuria glucosuria

hypoglycemia

Which of the following enzyme catalyzes the conversion of glucose to glucose-6-phosphate in muscle cells: Hexokinase Phosphoglucomutase Glucose-6-phosphatase Glucokinase

Glucose-6-phosphatase

Which of the following pathways of glucose metabolism is not catabolic: glycolysis oxidative decarboxylation of pyruvate pentose phosphate pathway gluconeogenesis

gluconeogenesis

Which of mentioned biomolecules is the major energetic source for skeletal muscles during their prolonged and medium-intensive activity (long distance running): glucose none of them fatty acids ketone bodies

ketone bodies

Which of the following statements about the mechanism by which insulin affects the activity of glycogen synthase (regulatory enzyme of glycogenogenesis) is wrong: 1. the active protein phosphatase-1 catalyzes the phosphorylation of glycogen synthase (glycogen synthase a) 2.insulin decreases the level of cAMP, which leads to dropout of the activation of protein kinase A, catalyzing the formation of the active phosphorylated form of the protein, called "inhibitor-1" 3.the action of insulin gives the phosphorylated form of glycogen synthase (glycogen synthase b) 4.when the inhibitory protein-1 is inactive (dephosphorylated) it does not inhibit the activity of proteinphosphstase – 1

2.insulin decreases the level of cAMP, which leads to dropout of the activation of protein kinase A, catalyzing the formation of the active phosphorylated form of the protein, called "inhibitor-1"

Which of the following alterations does not appear to be a reason for development of Diabetes type II (insulin-independent): 1.decreased affinity of the insulin receptor towards insulin 2.decreased synthesis of insulin receptors 3.synthesis of abnormal (defect) insulin 4.progressive destruction of the B-cells of pancreas by autoimmune mechanisms

4.progressive destruction of the B-cells of pancreas by autoimmune mechanisms

Which of the following glycolytic enzymes catabolize the metabolic steps leading to the formation phosphoenolpyruvate: enolase glycerate kinase aldolase pyruvate kinase

pyruvate kinase

The blood level of which of the mentioned metabolites is significantly increased during active muscle contraction: amino acids none of them glucose lactate

lactate

Which of the following statements about the malate-aspartate shuttle is not true: 1.the pair of substrates involved in the shuttle are oxaloacetate and malate 2.the shuttle is bidirectional 3.transferred by the shuttle mechanism, two pairs of reducing equivalents after their submission to the respiratory chain, lead to the synthesis of 4 ATP molecules 4.cytoplasmic and mitochondrial malate dehydrogenase participate in shuttle

3.transferred by the shuttle mechanism, two pairs of reducing equivalents after their submission to the respiratory chain, lead to the synthesis of 4 ATP molecules

Which of mentioned metabolic pathways in the liver for conversion of glucose do not occur during fasting (between meals): 1.gluconeogenesis 2.degradation of glycogen 3.degradation of glucose, in order to provide substrate for fatty acids synthesis 4.degradation of glucose-6-phosphste to glucose

4.degradation of glucose-6-phosphste to glucose

Which of the following enzymes involved in gluconeogenesis, it is the most important regulatory enzyme in the process, subjected to allosteric regulation of variety of modulators: pyruvate carboxylase fructose-1,6-bisphosphatase glucose-6-phosphatase phosphoenolpyruvate-carboxykinase (PEPCK)

fructose-1,6-bisphosphatase

Which of the following metabolites of glycolysis is obtained in an oxidation step and is a macroergic phosphate compound: glyceraldehyde 3-phosphate 1,3-bisphosphoglycerate phosphoenol pyruvate pyruvate

1,3-bisphosphoglycerate

Which of the mentioned mtabolites (substances) serves as an energetic source (alternative to glucose) during prolonged fasting: fructose glycerol ketone bodies

ketone bodies

Which of the following statements about the oxidative decarboxylation of pyruvate is wrong: the product of oxidative decarboxylation of pyruvate is Acetyl CoA oxidative decarboxylation of pyruvate is carried in multienzyme complex called pyruvate dehydrogenase complex oxidative decarboxylation of pyruvate takes place in the mitochondria NADP+ serves as a coenzyme in the pyruvate dehydrogenase complex and NADPH is obtained

NADP+ serves as a coenzyme in the pyruvate dehydrogenase complex and NADPH is obtained

In which of the following cells an anaerobic glycolysis is performed: white muscle fibers (during active contraction) cells of the renal medulla erythrocytes cells of the crystalline lens

erythrocytes

Which of the following glycolytic enzymes catalyzes an irreversible metabolic step: glycerate kinase aldolase glyceraldehyde 3-phosphate dehydrogenase pyruvate kinase

pyruvate kinase

Which of the following hormones by its effect on the liver cells, results in the formation of active kinase dephosphorylated form of the enzyme phosphofructokinase 2: Glucagon Adrenaline None of the mentioned above Insulin

Insulin

Which of the following pairs of hormones appears to be, depending on the quantitative ratio of their blood levels, the main regulator of the metabolism of energetic biomolecules (glucose, fatty acids): insulin / glucagon glucagon / cortisol insulin / cortisol glucagon / adrenaline

insulin / glucagon

Which of the following enzymes involved in the breakdown of carbohydrates in the digestive tract of humans, have small intestine origin? sucrose glucoamylase lactase α- amylase

lactase

Which of the following enzymes involved in glycogen metabolism, catalyzes the degradation of α-1,4-glycosidic bond: phosphoglucomutase amylo-1,4 → 1,6-transglucosidase glycogen phosphorylase glycogen synthase

glycogen phosphorylase

In insufficiency of which of the following enzymes involved in the degradation of galactose, pathological condition known as galactose intolerance or galactosemia develops: С4- epimerase galactose-1-phosphate-uridil transferase none of the mentioned above Galactokinase

galactose-1-phosphate-uridil transferase

To which of the following enzymes functioning in gluconeogenesis, acetyl-CoA is an allosteric activator: glucose-6-phosphatase PEPC pyruvate carboxylase fructose-1,6-bisphosphatase

pyruvate carboxylase

Which of the following statements about the structure of glycogen is wrong: glycogen molecule has a branched structure in the straight sections of the polysaccharide chains glucose residues are joined by α-1,4-glycosidic bond glycogen is heteropolysaccharide in the branches sections in the polysaccharide chain the bond is α-1,6-glycosidic

glycogen is heteropolysaccharide

Which of the following coenzymes is a cofactor of glyceraldehyde 3-phosphate dehydrogenase, which catalyses an oxidative step in glycolysis: FMN FAD NAD+ NАDP+

NAD+

Which of these metabolites is the allosteric activator of phosphorylated glycogen synthase b: АTP АМP glucose-6-phosphate fructose-2,6-bisphosphate

АМP

Which of the following metabolites of glucose is a a key metabolite of glucose metabolism: lactate glucose 6-phosphate fructose-1,6-biphosphate pentose-5-phosphate

glucose 6-phosphate

When you consider that for the synthesis of one molecule glucose in gluconeogenesis two molecules pyruvate are used, choose the correct answer of the question – how many molecules ATP are spent in the process of gluconeogenesis 3 molecules ATP 2 molecules ATP 6 molecules ATP neither one single molecule ATP

6 molecules ATP

In which of the following cell types malate-aspartate shuttle mechanism does not function: hepatocytes brain cells kidney cells heart muscle

brain cells

Which of the following enzymes of the glycolytic metabolic chain catalyzes the step, occurring phosphorylation in the substrate chain, ie carries out the synthesis of ATP: Phosphofructokinase 1 Phosphoglucomutase Hexokinase Pyruvatekinase

Phosphofructokinase 1

In the failure of which of these enzymes involved in the catabolism of fructose the hereditary disease "congenital fructose intolerance" is developed: triosokinase none of the above mentioned Fructokinase Aldolase B

Aldolase B

With the deficiency of which of the following enzymes of the pentose-phosphate pathway is associated the risk of hemolytic anemia: Phosphogluconolaktonase Transaldolase Transketolase Glucose-6-phosphate dehydrogenase

Glucose-6-phosphate dehydrogenase

Which of the following metabolites pairs performes the transfer of reducing equivalents of NAD.H from the cytosol to the respiratory chain in malate-aspartate shuttle mechanism: malate- aspartate malate/oxaloacetate none of the mentioned above DHAP / glycerol-3-phosphate

malate- aspartate

Which of the following statements about the metabolism of liver glycogen is true: a.its digested in periods of fasting b.glucagon stimulates its synthesis c.adrenaline stimulates its synthesis d.In its degradation lactate is released in the blood

In its degradation lactate is released in the blood

Which of mentioned biomolecules is the major energetic source for skeletal muscles during their intensive and non-continuous contractions: glucose none of them fatty acids ketone bodies

fatty acids

How many of the metabolic steps in glycolysis are irreversible 2 5 none 3

Which of the following symptoms are typical for mono- and disaccharidases malabsorption (intolerance) and lactose intolerance? 1) diarrhea 2) intestinal distension 3) painful colics 4) meteorism 1+3 2+4 1+2+3 1+2+3+4

1+3

Which of the following enzymes involved in the glycolysis is the major regulatory enzyme of glycolysis: Phosphofructokinase-2 (PFK-2) Phosphofructokinase-1 (PFK-1) Phosphoglycerate kinase Aldolase

Phosphofructokinase-1 (PFK-1)

Which of the following metabolic steps of gluconeogenesis is common for glycolysis and gluconeogenesis: fructose-1,6-bisphosphate → fructose-6-phosphate oxaloacetate → phosphonenolpyruvate pyruvate →oxaloacetate fructose-6-phosphate → Glucose-6-phosphate

fructose-1,6-bisphosphate → fructose-6-phosphate

By which of the following transports the transition of glucose through the luminal membrane of intestinal epithelial cells is performed: active transport enhanced diffusion and secondary active transport passive diffusion secondary active transport

secondary active transport

Glycerol is a non-carbohydrate precursor for the synthesis of glucose in gluconeogenesis.To which of the following metabolites of gluconeogenesis turns the glycerol to: phosphonenolpyruvate pyruvate dihydroxyacetone phosphate fructose-6-phosphate

dihydroxyacetone phosphate

Which of the listed deficiencies (of enzymes and / or vitamins) lead to lactic acidosis? 1)thiamine 2) erythrocyte enzymes of glycolysis 3) enzymes of pyruvate dehydrogenase complex 4) muscle enzymes of glycolysis

1)thiamine

Glycosylated hemoglobin is an indicator of: prolonged hyperglycaemia prolonged hypoglycaemia impaired pentose phosphate function reduced glucose uptake into erythrocytes

prolonged hyperglycaemia

Which of the following enzymes catalyzes the synthesis of fructose-2,6-bisphosphate, appearing as the strongest activator of the regulatory enzyme of glycolysis: hexokinase phosphofructokinase 2 phosphofructokinase 1 phosphoglycerate kinase

phosphofructokinase 2

Which of the following statements about the enzyme glucose-6-phosphatase is wrong: a.the highest concentration of enzyme is found in skeletal muscle cells b.the synthesis of the enzyme is induced by the hormone cortisol c.the enzyme is localized in the endoplasmic reticulum d.the enzyme catalyzes the hydrolysis of glucose-6-phosphate to glucose-free, as it passes from the liver into the blood to maintain normal blood glucose level

a.the highest concentration of enzyme is found in skeletal muscle cells

Which of the following statements about the transport of glucose from the blood into the cells of skeletal muscle is wrong: a.the insulin induces the biosynthesis of an enzyme which catalyzes phosphorylation of b.the free glucose to glucose-6-phosphate c.the transport is carried out by a glucose transporter (facilitated diffusion) d.the glucose enters the cells of the skeletal muscle by the concentration gradient e.insulin stimulates glucose transport through the export of glucose carriers from the cell on the cell membrane, i.e. - By increasing the number of transporters on the cell membrane

d.the glucose enters the cells of the skeletal muscle by the concentration gradient

Which of the following statements about the influence of insulin on blood glucose level is wrong: a.stimulates glycolysis in the liver b.does not stimulate glucose transport in adipose tissue c.reduces the level of blood glucose by accelerating its transport from the blood into d.insulin-dependent tissues e.stimulates the synthesis of liver and muscle glycogen

b.does not stimulate glucose transport in adipose tissue

In which of the following types of cells the transport of glucose is insulin-independent: 1) adipocytes 2) brain 3) skeletal muscle cells 4) erythrocytes

2) brain 4) erythrocytes

Which amino acids are required for the synthesis of creatine phosphate? 1) tyrosine; 2) glycine; 3) arginine; 4) lysine; 5) methionine 1+2+5 2+3+5 1+2+3 1+3+4 2+4+5

2+3+5

The simultaneous increase of the AST and ALT serum levels is used to diagnose a disease of the: brain muscules stomach prostate liver

liver

Which of the following chemical bonds/interactions are involved in stabilizing the tertiary structure of proteins? 1) ion, dipole and ion-dipole interactions; 2) hydrophobic interactions; 3) peptide bonds; 4) hydrogen bonds between radicals; 5) hydrogen bonds between closely spaced peptide groups 1+3+5 1+2+4 2+3+4 1+4+5 1+2+3

2+3+4

Identify the true statements about glutamate dehydrogenase. 1) oxidatively deaminates glutamate together with NAD; 2) reductively aminates α-ketoglutarate together with NADPH; 3) oxidatively deaminates glutamate together with FAD; 4) it is activated allosterically by ATP and GTP 5) it is localized in the mitochondria. 1+2+4 1+2+5 2+3+4 1+4+5 2+3+5

2+3+5

User Which of the following changes are observed in hemolytic jaundice? 1) increased urobilinogen in urine; 2) increased bilirubin in urine; 3) very dark stools; 4) increased indirect bilirubin in serum; 5) increased direct bilirubin in serum. 1+2+3 1+3+4 1+4+5 2+3+4 2+4+5

1+3+4

Heme biosynthesis is a process: 1) that is highly prevalent in the liver and bone marrow; 2) localized in mitochondria and cytosol of cells; 3) which is highly prevalent in mature erythrocytes; 4) which requires succinyl-CoA and glycine; 5) which requires carbamoyl phosphate and aspartate. 1+3+4 1+3+5 1+2+4 2+3+4 2+3+5

2+3+4

1+2+4

Indicate the correct answers describing the features of the protein ubiquitin. 1) it is a protein fragment obtained as a result of the proteolytic maturation of the insulin molecule; 2) it is a protein fragment obtained as a result of the proteolytic maturation of pituitary hormones; 3) it is a small protein that binds covalently to other proteins through its glycine terminal carboxyl group and marks them for subsequent degradation; 4) it is an enzyme that is found in all cells and participates in processes of proteolytic maturation of hormones; 5) it is a protein through which the cell directs "aged" proteins to the proteasome, where they are degraded. 1 + 3 2 + 3 3 + 4 3 + 5 4 + 5

3 + 5

The chemical bond between the pentose and the phosphoric acid in nucleotides is: О-glycosidic N-glycosidic phosphodiester bond ester bond peptide bond

phosphodiester bond

Which of the end products of heme degradation are increased in parenchymal jaundice? 1) urobilinogen in urine; 2) bilirubin in urine; 3) indirect bilirubin in serum; 4) direct bilirubin in serum; 5) stercobilin in feces. 2+4 1+3 1+2 3+4 4+5

4+5

Carbamoylphosphate synthetase I, supplying carbamoylphosphate for the urea cycle: 1) is located in the mitochondria of hepatocytes; 2) is located in the cytosol of hepatocytes; 3) is a regulatory enzyme; 4) is activated allosterically by N-acetylglutamate; 5) is activated allosterically by N-acetylglutamine. 1+2+4 1+4+5 3+4+5 1+3+4 2+3+5

1+2+4

Which of the following enzymes in the synthesis of purine nucleotides are under allosteric control? 1) phosphoribosylpyrophosphate synthetase; 2) formyl transferase; 3) glutamine-phosphoribosylpyrophosphate amidotransferase; 4) adenylosuccinate lyase; 5) xanthine oxidase. 2+5 1+3 1+4 2+3 4+5

1+3

Which of the following molecules are produced when heme is broken down? 1) uric acid; 2) bilirubin; 3) biliverdin; 4) urea; 5) creatinine. 1+2 1+3 2+3 3+4 2+5

2+3

Heme is a cofactor of: 1) phosphofructokinase-1; 2) citrate synthase; 3) cytochromes; 4) ATP synthase; 5) catalase. 1+2 2+3 3+4 4+5 3+5

3+5

Tyrosine is the precursor for the synthesis of: 1) NAD; 2) melanine; 3) melatonin; 4) thyroid hormones; 5) corticosteroids. 1+2 2+4 2+3 2+5 4+5

2+3

Which disease occurs with a genetic defect in an enzyme that breaks down valine, isoleucine, and methionine? pellagra alkaptonuria merhylmalonylemina albinism Lesch-Nyhan syndrome

merhylmalonylemina

What features are characteristic of hemoglobin? 1) consists of 4 different polypeptide chains; 2) consists of 4 polypeptide chains, two by two identical; 3) each polypeptide chain contains heme; 4) heme iron is divalent; 5) heme iron is trivalent. 1+3+5 2+3+5 1+3+4 2+3+4 1+2+3

2+3+4

The breakdown of heme produces: 1) carbon monoxide; 2) carbon dioxide; 3) bile acids; 4) bile pigments; 5) uric acid. 4+5 1+4 1+2 2+3 1+5

4+5

Indicate the true statements about folic acid. 1) its active form is tetrahydrofolate; 2) its active form is dihydrofolate; 3) supplies one-carbon groups for the synthesis of the purine ring; 4) supplies one-carbon groups for the synthesis of the pyrimidine ring; 5) supplies one-carbon groups for creatine synthesis. 2+4 4+5 1+3 1+2 3+5

1+3

Identify the true statements about the synthesis of pyrimidine nucleotides. 1) the pyrimidine ring is built on a ribose phosphate residue; 2) the pyrimidine ring is formed first and then a ribose phosphate residue is added to it; 3) tetrahydrofolate derivatives are needed to obtain dTMP; 4) S-adenosylmethionine is required to produce dTMP; 5) all enzymes have a cytosolic localization. 2+5 1+3 1+2 2+3 4+5

2+3

Identify the true statements about phenylketonuria. a. It is caused by deficiency of phenylalanine hydroxylase. b. It is caused by hyperactive phenylalanine hydroxylase. c. It is characterized by an accumulation of homogentisinate d. It is characterized by an accumulation of tryptophan. e. It is caused by reduced activity of dihydrofolate reductase.

a. It is caused by deficiency of phenylalanine hydroxylase. c. It is characterized by an accumulation of homogentisinate

The nitrogen atom in carbamoyl phosphate required for the synthesis of pyrimidines originates from: glutamate ammonia aspartate glutamine glycine

ammonia

Which vitamin is present in the structure of FAD and FMN? Vit B1 (thiamin) Vit B2 (riboflavin) Vit B3 (niacin) Vit B9 (folic acid) Vit B12 (cobalamin)

Vit B2 (riboflavin)

Which of the following compounds is NOT a metabolite involved in porphyrin biosynthesis? porphobilinogen glycine succinyl-CoA uroporphyrinogen UDP-glucuronate

UDP-glucuronate

Which of the following reactions requires S-adenosylmethionine as a methyl group donor? The conversion of norepinephrine to epinephrine The conversion of phenylalanine to tyrosine. The synthesis of purines. The conversion of dUMP to dTMP. The conversion of glutamate to glutamine.

The conversion of norepinephrine to epinephrine

Which of the following compounds is a cofactor of the enzymes heme oxygenase and biliverdin reductase? UDP-glucoronate NADH pyridoxal phosphate NADPH ascorbic acid

NADPH

Which are the regulatory enzymes in the synthesis of pyrimidine nucleotides? 1) carbamoyl phosphate synthetase II; 2) dihydroorotase; 3) dihydroorotate dehydrogenase; 4) aspartate transcarbamoylase; 5) carbamoyl phosphate synthetase I. 1+3 1+4 2+5 3+5 4+5

1+4

Cytotoxic ammonia is neutralized by: 1) the synthesis of glutamine in the brain; 2) the synthesis of alanine in muscles; 3) transdeamination reactions; 4) formation of ammonium ions in the brain; 5) reductive amination of alpha-ketoglutarate. 1+2+4 1+2+5 2+3+4 1+4+5 2+3+5

1+2+5

Which biosynthetic processes take place with the participation of tetrahydrofolic acid derivatives as cofactors? 1) the synthesis of purines (C2 and C8 atoms); 2) the synthesis of choline from ethanolamine; 3) the synthesis of methionine from homocysteine; 4) creatine synthesis; 5) the synthesis of TMF.

1) the synthesis of purines (C2 and C8 atoms); 3) the synthesis of methionine from homocysteine; 5) the synthesis of TMF.

Which of the following enzymes in the synthesis of pyrimidine nucleotides are under allosteric control? 1) carbamoyl phosphate synthetase II; 2) dihydroorotase; 3) dihydroorotate dehydrogenase; 4) aspartate transcarbamoylase; 5) orotate phosphoribosyltransferase. 2+5 1+4 1+3 3+4 1+5

1+4

Tyrosinemias are observed in genetically determined insufficiency of enzymes from the catabolite chain of: histidine tryptophan valine leucine phenylalanine

phenylalanine

Which amino acids are sources of one-carbon residues for tetrahydrofolic acid? serine, histidine, arginine serine, tyrosine, tryptophan histidine, glycine, valine tryptophan, histidine, glutamate serine, histidine, tryptophan

serine, histidine, arginine

The function of haptoglobin is: 1) to bind free heme; 2) to participate in the synthesis of hemoglobin for erythrocytes; 3) to transport the hemoglobin/haptoglobin complex through the kidneys; 4) to prevent loss of hemoglobin from the kidneys; 5) to preserve iron in the body. 3+5 1+3 2+4 4+5 1+2

3+5

Which statements are true about the hormone hepcidin? 1) increases serum iron content; 2) lowers serum iron content; 3) binds to the iron exporter ferroportin; 4) binds to the iron transport protein transferrin; 5) binds to the iron-depositing protein ferritin. 2+5 1+3 1+4 2+3 4+5

2+3

Protein denaturation is a process that: 1) changes the amino acid composition of the protein molecule; 2) destroys the primary structure of the protein molecule; 3) leads to loss of biological activity of the protein; 4) increases the chemical reactivity of the polypeptide chain of the protein; 5) destroys the secondary, tertiary and quaternary level of organization of the protein 1+2+5 3+4+5 1+2+3 2+3+5 1+3+4

2+3+5

Which cofactors are involved in the oxidative decarboxylation of α-keto acids? 1) NAD+; 2) NADP+; 3) lipoic acid; 4) ascorbic acid; 5) coenzyme A (CoA-SH). 1+3+4 1+3+5 2+3+4 2+3+5 3+4+5

1+3+5

The amino acid arginine is NOT a precursor for the synthesis of: creatine phosphate ethanolamine nitric oxide ornithine polyamines

ethanolamine

Which nucleotide is a secondary mediator of the action of adrenaline in muscles and glucagon in liver? ATP ADP AMP cyclic 3',5'-АMP cyclic 3',5'-GMP

AMP

Which of the following statements about the quaternary structure of proteins are true? 1) the achievement of such a structure is due to non-covalent (weak) interactions between two or more polypeptide chains; 2) proteins with a quaternary structure represent supramolecular complexes made up of two or more polypeptide chains (subunits) connected by covalent bonds; 3) the quaternary structure is mandatory for the manifestation of the biological activity of proteins; 4) the quaternary structure is necessary for those proteins that will be targeted for degradation; 5) the acquisition of a quaternary structure is one of the reasons for the existence of different isoforms and regulation in some proteins. 1+5 1+3 2+4 3+5 1+4

1+5

Which of the following statements about the urea cycle are true? 1) occurs in the mitochondria and the cytosol; 2) occurs in endoplasmic reticulum and cytosol; 3) proceeds in the liver; 4) occurs intensively after taking a balanced meal; 5) does not require energy. 3+5 1+2 4+5 1+3 2+4

1+3

Name the enzymes involved in the folding of polypeptide chains. 1) prolyl cis-trans isomerase; 2) protein disulfide isomerase; 3) prolyl hydroxylase; 4) lysyl hydroxylase; 5) chaperones. 1+2+5 2+3+4 1+2+3 1+4+5 1+3+4

1+2+5

Which of the following statements about nucleosides are true? 1) they consist of nitrogen base and pentose; 2) in the structure of nucleic acids they are connected by 3'-5'-phosphodiester bonds; 3) The N-glycosidic bond between the base and the pentose in purine nucleosides is at N1; 4) The N-glycosidic bond between the base and the pentose in pyrimidine nucleosides is at N1; 5) syn-conformers of nucleosides predominate. 3+5 3+4 1+2 1+4 2+5

1+4

Which of the following chemical bonds/interactions are involved in stabilizing the secondary structure of proteins? ion, ion-dipole, dipole interactions hydrogen bonds between side radicals of closely positioned amino acids peptide bonds disulfide bonds hydrogen bonds between closely positioned peptide groups

hydrogen bonds between side radicals of closely positioned amino acids

Identify the correct neurotransmitter/amino acid combination from which the corresponding neurotransmitter is synthesized. gamma-aminobutirate from glutamate gamma-aminobutirate from aspartate serotonin from tyrosine serotonin from sulfur-containing amino acids norepinephrine and epinephrine from tryptophan

gamma-aminobutirate from glutamate

Which of the following statements about heme synthesis are true? 1) the main regulatory enzyme is δ-aminolevulinate (ALA) dehydratase; 2) the main regulatory enzyme is δ-aminolevulinate (ALA) synthase; 3) heme is a major allosteric inhibitor of the regulatory enzyme; 4) porphyria can develop with ALA-synthase deficiency; 5) heme is synthesized in the bone marrow and liver. 2+4+5 1+3+4 2+3+5 1+4+5 1+2+3

2+4+5

Which of the following proteins are involved in iron transport? 1) transferrin; 2) ceruloplasmin; 3) lactoferrin; 4) ferritin; 5) hemosiderin. 2+5 1+3 1+2 2+4 4+5

1+3

How are purine nucleotides synthesized in the “de novo” pathway? 1) the synthesis starts from carbamoyl phosphate and aspartate; 2) synthesis starts from glycine and aspartate; 3) the purine ring is built by attaching atoms to phosphoribosylpyrophosphate; 4) the phosphoribosyl residue joins an already formed purine ring; 5) glycine and glutamine are involved in the synthesis. 1+2 2+4 2+5 3+5 4+5

1+2

Which of the following statements about the iron metabolism is true? physiologically, iron is deposited in the form of hemosiderin transferrin can only bind heme iron transferrin can only bind the ferrous (Fe2+) form of iron hepcidin lowers serum iron by blocking ferroportin hepcidin lowers serum iron by activating ferroportin

hepcidin lowers serum iron by blocking ferroportin

In transamination: 1) amino acids are converted into biogenic amines; 2) one amino acid is converted to a keto acid and another keto acid is converted to an amino acid; 3) pyridoxal phosphate is involved as a cofactor; 4) amino groups of amino acids are released as free ammonia; 5) NADPH is involved as a cofactor 1+2 2+4 2+3 2+5 4+5

2+3

1+2+4

Which of the following substances are ketone bodies with metabolic importance for tissues: 1)acetoacetate 2) oxaloacetate 3) β- hydroxybutyrate 4) acetone 1+2+3 2+3+4 2+3 1+3

1+3

Which of the following cofactors supplies reducing equivalents for the action of the enzyme HMG-CoA reductase? NADP.Н none of the above mentioned FAD.Н2 NAD.H

NAD.H

Which of the enzymes who catalyze reactions in the synthesis of glycerolipids is regulatory? glycerol-3P-acyltransferase phosphatide phosphatase phosphatidylinositol synthase diacylglycerol acyltransferase

diacylglycerol acyltransferase

Which of the following statements for the synthesis of saturated fatty acids with an even number of carbon atoms (palmitic acid) is false? synthesis takes place in the cytosol NAD.H serves as a donor of reducing equivalents NADP.H serves as a donor of reducing equivalents direct substrate for the synthesis is malonyl-CoA

NAD.H serves as a donor of reducing equivalents

Which of the following statements about the regulation of enzyme activity of 7α-hydroxylase which regulates the conversion of cholesterol to bile acids in the liver is false? a. the catalytic activity of 7α-hydroxylase is regulated by phosphorylation / dephosphorylation, and the active form of b. the enzyme is dephosphorylated c. bile acids inhibit the enzyme d. cholesterol activates 7α-hydroxylase e. in vit. C deficiency catalyzed by 7α-hydroxylase metabolic step slows down

d. cholesterol activates 7α-hydroxylase

Which of the following coenzymes serves as a donor of reducing equivalents in the synthesis of fatty acids in acyl synthetase complex? FMN.Н2 FAD.Н2 NADP.Н NAD.Н

NADP.Н

A key metabolite in the synthesis of cholesterol and ketone bodies is a one of the following compounds: a. mevalonic acid b. NADPН+Н+ c. 3-hydroxy-3-methylglutaryl-CоА d. squalene

c. 3-hydroxy-3-methylglutaryl-CоА

Which of the following statements about the physiological functions of eicosanoids is false? a. participate in inflammatory processes in injuries and infections b. all eicosanoids act as vasoconstrictors c. some of them regulate smooth muscle contractions (intestine, uterus) d. some of the eicosanoids are involved in platelet aggregation

b. all eicosanoids act as vasoconstrictors

Increased concentrations of which of these transport forms of lipids decreases the risk of developing atherosclerosis and coronary heart disease? LDL IDL VLDL HDL

HDL

Which of the following biological functions of cholesterol is not true? a. cholesterol serves as a precursor for bile acids synthesis b. cholesterol serves as a precursor for steroid hormone synthesis c. cholesterol serves as a precursor for vitamin E synthesis d. cholesterol participates in the construction of the cell e. membranes as a stabilizing component

c. cholesterol serves as a precursor for vitamin E synthesis

Oxidation of unsaturated fatty acids occurs in: mitochondria cytoplasm lysosomes endoplasmic reticulum

endoplasmic reticulum

Which of the following mechanisms activating the biosynthesis of fatty acids from insulin is incorrect? a. insulin with its action gives the active nonphosphorylated form of the regulatory enzyme acetyl-CoA carboxylase b. insulin with its action activates the enzyme glycerol-3-phosphate acyl transferase, forming its nonphosphorilated c. insulin with its action induces the biosynthesis of the regulatory enzyme of fatty acid synthesis - acetyl-CoA carboxylase d. insulin with its action induces the biosynthesis the multifunction enzyme of acyl synthetase complex (АSC)

b. insulin with its action activates the enzyme glycerol-3-phosphate acyl transferase, forming its nonphosphorilated

Which of the following types of lipids is not a component of the membrane structures? cholesterol triacylglycerols cardiolipins phosphatidylethanolamine

triacylglycerols

Which of the following reactions and processes provide reducing equivalents (NADPH) used in the synthesis of FA? 1) anaerobic glycolysis 2) pentose phosphate pathway 3) reaction catalyzed by malate dehydrogenase 4) reaction catalyzed by malate enzyme 2+3 2+4 2+3+4 1+2+3

2+3

Which of the following statements about the metabolism of energetic biomolecules in a patient suffering from a carnitine deficiency is wrong? there will be deficiency of ATP for gluconeogenesis leading to lowering glucose level in the blood (hypoglycaemia) in fasting state. the levels of fatty acids in the blood will be low the transport of long-chain fatty acids into the mitochondria of hepatocytes will be reduced and β-oxidation of fatty acids will be slower ketone bodies synthesis will be reduced and their level in the blood will be low

the levels of fatty acids in the blood will be low

Which of the following compounds are cholesterol derivatives? 1)aldosterone 2) adrenaline 3)cortisol 4)cholic acid 3+4 1+2+3 1+3 1+3+4

1+3

Which enzyme is involved in the synthesis of cholesterol esters in HDL? lecithin - cholesterol acyltransferase (LCAT) Acetyl-CoA-cholesterol acyltransferase-(ACAT) Pancreatic lipase hormone-dependent lipase

lecithin - cholesterol acyltransferase (LCAT)

Eicosatetraenoic acid (C20, 4:5,8,11,14) is a precursor for the synthesis of: 1) prostanoids with 2 double bonds 2) leukotrienes with 3 double bonds 3) lipoxins with 4 double bonds 4) none of the above mentioned 1+3 2+4 1+2+3 none

2+4

Which of the following hormones stimulates ketogenesis in periods of fasting? cortisol glucagon none of the above mentioned insulin

glucagon

How many metabolic steps are required for the decoupling (oxidation) of each two-carbon fragment of the long fatty acid chain in β-oxidation? 8 4 6 2

Which of the following types of genetic defects, leading to development of inherited hyperlipoproteinemias, is the cause of familial hypercholesterolemia, characterized by elevated blood levels of LDL and considered as a risk factor for atherosclerosis? genetic defects affecting enzymes (for example, lipoprotein lipase or lecithin-cholesterol acyltransferase-) involved in the metabolism of lipoproteins genetic defects resulting in decreased synthesis of receptor LDL none of them genetic defects affecting the synthesis, structure, or secretion of apoproteins

genetic defects resulting in decreased synthesis of receptor LDL

Which of the following compounds is a key (a key metabolite) in the synthesis of most glycerolipids? phosphatidic acid choline CDP-choline CDP- diacylglycerol

CDP- diacylglycerol

Which of the following metabolites is a product of the degradation of ketone bodies (ketolysis)? acetyl-CоА malonyl -CоА none of the above mentioned succinyl -CоА

acetyl-CоА

The oxidative phase of the PPP (pentose phosphate pathway) is important for: 1) cholesterol synthesis 2) synthesis of ATP 3) FA synthesis 4) gluconeogenesis none 2+4 1+3 1+2+3

1+3

Which of the following pathways of lipid metabolism occurring in adipose tissue is stimulated by insulin? fatty acids synthesis (lipogenesis) none of them triacylglycerols degradation (lipolysis) fatty acids degradation (β-oxidation)

fatty acids synthesis (lipogenesis)

Which of the following essential polyunsaturated FA (PUFA) are supplied only from foods of animal origin. 1)linoleic acid 2)arachidonic acid 3)eicosapentaenoic acid 4)linolenic acid 2+3+4 2+3 1+4 1+2+3

2+3

Which of the following compounds is the direct donor of 14 of the 16 carbon atoms in the synthesis of palmitic acid? malonyl-CоА acyl-CоА acetyl-CоА methilmalonyl-CоА

acetyl-CоА

Which of the following lipoprotein complexes transport the "Bad" cholesterol and raising of their levels is a risk factor for atherosclerosis? LDL VLDL HDL chylomicrons

VLDL

Which of the following biological effects are typical for PGE2? 1)bronchoconstrictor 2)vasodilator 3)inhibits the secretion of gastric juice 4) inhibits the uterine contractions 2+4 2+3+4 1+2+3 2+3

2+3+4

Which of the following enzymes is regulatory in degradation of triacylglycerols in adipose tissue? lipoprotein lipase adipolitic lipase phospholipase glycerol kinase

adipolitic lipase

Which of the following statements about the activity of the regulatory enzyme of fatty acid biosynthesis, acetyl-CoA carboxylase is false? the activity is influenced by the action of hormones,as insulin stimulates the enzymatic activity the activity is regulated by the mechanism of covalent modification (phosphorylation / dephosphorylation), аs the active form is phosphorylated. the activity is regulated by the mechanism of covalent modification (phosphorylation / dephosphorylation), the active form is dephosphorylated. the activity of the enzyme is regulated allosterically as citrate is allosteric activator

the activity is regulated by the mechanism of covalent modification (phosphorylation / dephosphorylation), аs the active form is phosphorylated.

Which of the following statements about ketone bodies is wrong? substrate for the synthesis of ketone bodies is acetyl CoA, obtained from the oxidative decarboxylation of pyruvate ketone bodies are acetoacetate, β-hydroxybutyrate and acetone, as acetone is product of acetoacetate degradation. ketone bodies are an energy source alternative of glucose the concentration of the β-hydroxybutyrate in the blood is usually higher than that of the acetoacetate

ketone bodies are acetoacetate, β-hydroxybutyrate and acetone, as acetone is product of acetoacetate degradation.

Which of the following nucleoside-triphosphate is used to activate the so-called "polar head" in the synthesis of phosphoglycerides? GTP CTP none of them UTP

CTP

Arachidonic acid is converted to biologically active eicosanoids in two metabolic pathways: cyclooxygenase and lipoxygenase. Which of the following statements about obtaining the eicosanoids is wrong? aspirin is an irreversible inhibitor of the enzyme lipoxygenase lipoxins are obtained by successively co action of 2 lipoxygenases in the lipoxygenase pathway occurs the synthesis of leukotrienes in the cyclooxygenase pathway the synthesis of prostaglandins and thromboxanes is performed

aspirin is an irreversible inhibitor of the enzyme lipoxygenase

Which of the following foods does not supply cholesterol in the human body? brain liver egg yolk sunflower seeds

sunflower seeds

Which of the following enzymes catalyze the hydrolysis of triacylglycerols located in different lipoprotein complexes (eg. in chylomicrons, VLDL)? lecithin-cholesterol-acyltransferase lipoprotein lipase pancreatic lipase adipolithyc lipase

lipoprotein lipase

In which of the following cell compartments, except mitochondria, the oxidation of fatty acids may occur? cytosol endoplasmic reticulum peroxisomes lysosomes

peroxisomes

In which of the following compartments of hepatocytes ketogenesis occurs ? endoplasmic reticulum cytosol lysosomes mitochondria

mitochondria

By which of the following shuttle mechanisms the transfer of activated fatty acids from the cytosol into the mitochondria is performed? acyl-carnitine none of the above mentioned malate-aspartate glycero phosphate

acyl-carnitine

At which positions in the fatty acids' chains double bonds are introduced in humans ? 5, 8, 11 and 14 4, 5, 6 and 9 Опция 4 4, 5, 8 and 9

4, 5, 8 and 9

Which of the following enzymes play an important role in the metabolism of lipoprotein complexes: 1)hepatic lipase 2)pancreatic lipase 3)lipoprotein lipase 4)LCAT (lecithin cholesterol acyltransferase) 3+4 1+2 1+3+4 1+2+3

1+2

By which of the following substances the bile acids are conjugated (primary bile acids)? none of them glutathione glucuronic acid taurine

taurine

Which of the following statements about the cholesterol synthesis is wrong? cholesterol synthesis begins in the cytosol and continues and ends in the endoplasmic reticulum (microsomal fraction) in the human body a large amount of cholesterol is synthesized in the intestinal mucosal cells over 50% of the cholesterol in the human body resulted from endogenous synthesis cholesterol synthesis occurs in the mitochondria

cholesterol synthesis occurs in the mitochondria

Which of the following statements about the activation of fatty acids before their inclusion in β-oxidation is wrong? activation of fatty acids is by connecting them with coenzyme A and turning them into acyl CoA derivatives activation of the fatty acids takes place in the mitochondrial matrix long chain fatty acids are activated activation of the fatty acids takes place in the endoplasmic reticulum

activation of the fatty acids takes place in the endoplasmic reticulum

How are the low-density lipoproteins (LDL) are assumed by the cells (entering from the blood into the cells)? by passive diffusion by facilitated diffusion by receptor-mediated endocytosis by secondary active transport

by receptor-mediated endocytosis

In which of the following organs takes place the synthesis of ketone bodies (ketogenesis)? skeletal muscle brain liver heart muscle

liver

Which of the following lipoprotein complexes are the basic carriers of TAG to peripheral tissues: 1)Chylomicrons 2)VLDL 3)LDL 4)HDL 1+2+3 1+2 1+3+4 3+4

1+2

Which of the following compounds are not allosteric activators of the main key enzyme in the synthesis of FA, Acetyl CoA carboxylase? 1) acyl-CоА 2)acetyl-CоА 3)malonyl-CоА 4)citrate 1+2+3 2+4 2+3 2+3+4

2+4

All of the following fatty acids are synthesized in the human body by the exception of one. Which is it? palmitic acid linoleic acid oleic acid stearic acid

linoleic acid

Which of the following groups of lipids are glycolipids? 1)sphingomyelins 2)gangliosides 3)cerebrosides 4)lecithins 1+2+3 2+3+4 1+4 2+3

2+3

1. Which of the following enzymes, involved in the breakdown of carbohydrates in the digestive tract of humans, has/have small intestine origin? 1) sucrase 2) glucoamylase 3) lactase 4) α- amylase a) 1+2+3 b) 1+3 c) 2+4 d) 4

a) 1+2+3

3. Which of the following symptoms are typical for mono- and disaccharidases malabsorption (intolerance) and lactose intolerance? 1) diarrhea 2) distension the intestine 3) painful colics 4) meteorism a) 1+2+3 b) 1+3 c) 2+4 d) 1+2+3+4

d) 1+2+3+4

5. Which of the following enzymes involved in the glycolysis is the major regulatory enzyme of this pathway: a) Phosphofructokinase-2 (PFK-2) b) Aldolase c) Phosphoglycerate kinase d) Phosphofructokinase-1 (PFK-1)

d) Phosphofructokinase-1 (PFK-1)

7. In which of the following cells the anaerobic glycolysis is performed: 1) white muscle fibers (during active contraction) 2) cells of the renal medulla 3) erythrocytes 4) cells of the eye lens a) 1+2+3 b) 1+3 c) 2+4 d) 1+2+3+4

d) 1+2+3+4

8. Which of the following substances is a direct product of the action of the enzyme glycogen phosphorylase (glycogenolysis): a) Glucose-6-phosphate b) Glucose c) Glucose-1-phosphate d) None of the mentioned above

c) Glucose-1-phosphate

10. Which of the following enzymes uses NAD.H as coenzyme in reduction process in anaerobic glycolysis: a) Pyruvate kinase b) Enolase c) Lactate dehydrogenase

c) Lactate dehydrogenase

11. Which of the following statements about the malate-aspartate shuttle is not true: a) The shuttle is bidirectional b) Cytoplasmic and mitochondrial malate dehydrogenases participate in the shuttle c) The oxidation in the respiratory chain of the two pairs of reducing equivalents transferred by the shuttle mechanism, leads to the synthesis of 4 ATP molecules d) The pair of substrates involved in the shuttle are oxaloacetate and malate

c) The oxidation in the respiratory chain of the two pairs of reducing equivalents transferred by the shuttle mechanism, leads to the synthesis of 4 ATP molecules

22. Which of the following co-enzymes serve as such of the enzyme of the pentose phosphate pathway, transketolase, and by measuring the enzymatic activity of transketolase is diagnosed a possible deficiency of this vitamin in the body: a) pyridoxal phosphate b) thiamine pyrophosphate c) NADP d) FAD

b) thiamine pyrophosphate

23. In which of the following types of cells the transport of glucose is insulin-independent: 1) adipocytes 2) brain 3) skeletal muscle cells 4) erythrocytes a) 1+2+3 b) 1+3 c) 2+4 d) None of the above mentioned

c) 2+4

24. Which of the following statements about the pentose phosphate pathway in mature erythrocytes is true: a) Provides ribose-5-phosphate for the synthesis of nucleotides b) Provides NADPH for fatty acid synthesis c) Provides NADPH for maintaining the level of reduced glutathione, necessary for the disposal of Н2О2 d) Provides NADPH of cholesterol synthesis

c) Provides NADPH for maintaining the level of reduced glutathione, necessary for the disposal of Н2О2

25. Which of the following statements about the transport of glucose from the blood into the cells of skeletal muscle is wrong: a) the transport is carried out by a glucose transporter (facilitated diffusion) b) insulin stimulates glucose transport through the export of glucose carriers on the cell membrane, i.e. by increasing the number of transporters on the cell membrane c) the glucose enters the cells of the skeletal muscle along the concentration gradient d) Insulin induces the biosynthesis of an enzyme which catalyzes phosphorylation of the free glucose to glucose-6-phosphate

d) Insulin induces the biosynthesis of an enzyme which catalyzes phosphorylation of the free glucose to glucose-6-phosphate

42. Which of the following statements about the metabolism of liver glycogen is wrong: a) it is synthesized after carbohydrate-rich food intake b) insulin stimulates its synthesis c) it is broken down in conditions with high blood glucose levels d) by degradation it provides blood glucose

d) by degradation it provides blood glucose

d) phosphoenolpyruvate-carboxykinase (PEPKK) 29. Which of the following hormones stimulates the gluconeogenesis by inducing biosynthesis of phosphoenolpyruvate-carboxykinase (PEPKK) and other specific enzymes of gluconeogenesis: a) Cortisol b) Insulin c) Aldosterone d) Adenocorticotropic hormone (ACTH)

a) Cortisol

46. Which of the following statements about the effects of cortisol on the blood glucose level is correct: a) cortisol increases blood glucose level by stimulating the glycogenolysis b) cortisol increases blood glucose level by stimulating gluconeogenesis c) cortisol decreases blood glucose level by increasing the uptake of glucose into cells d) cortisol decreases blood glucose level by stimulating the glycolysis

b) cortisol increases blood glucose level by stimulating gluconeogenesis

43. Which of the following statements about the influence of insulin on blood glucose level is wrong: a) Insulin reduces the level of blood glucose by accelerating its transport from the blood into insulin-dependent tissues b) Insulin stimulates the synthesis of liver and muscle glycogen c) Insulin does not stimulate glucose transport in adipose tissue d) Insulin stimulates glycolysis in the liver

c) Insulin does not stimulate glucose transport in adipose tissue

47. Which of the following statements about the mechanism by which insulin affects the activity of glycogen synthase (regulatory enzyme of glycogenogenesis) is wrong: a) insulin decreases the level of cAMP, which leads to dropout of the activation of Protein kinase A, catalyzing the formation of the active phosphorylated form of the protein, called "inhibitor-1" b) When the inhibitory protein-1 is inactive (dephosphorylated) it does not inhibit the activity of proteinphosphstase – 1 c) the active protein phosphatase-1 catalyzes the dephosphorylation of glycogen synthase (glycogen synthase a) d) insulin signaling leads to creating of the phosphorylated form of glycogen synthase (glycogen synthase b)

d) insulin signaling leads to creating of the phosphorylated form of glycogen synthase (glycogen synthase b)

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