| Energy transfer from catabolic reactions to energy-consuming processes is achieved
through: | the energy transfer is carried out through all the above-mentioned compounds. |
| The tricarboxylic acid cycle (citric acid cycle or Krebs cycle) aims to: | answers b and d are correct
transfer of hydrogen from acetyl coenzyme A to NAD + and FAD coenzymes
removal of carbon atoms from the acetyl radical in the form of CO2 |
| In order to be absorbed, the oligo- and polysaccharides compounds from food are digested
under the action of enzymes called: | glycosidases |
| The starch in the food is completely hydrolyzed to maltose at the level: | small intestine, under the action of the pancreatic α-amylase enzyme |
| The statement about lactose is correct: | it is hydrolyzed into α-glucose and β-galactose by the action of lactase produced by the
intestinal mucosa. |
| The statement about glycogenolysis is correct: | it is a phosphorylation process by which phosphorylated glucose molecules are released,
under the action of phosphorylase a; |
| Choose the correct statement: | the end product of glucose degradation in cells without mitochondria is lactic acid |
| By going through the cytoplasm stages of glycolysis, 2 moles of glyceraldehyde-3-
phosphate lead to: | 4 moles ATP |
| Glyceraldehyde-3-phosphate dehydrogenase enzyme catalyzes: | all previous answers are correct |
| The enzyme lactate dehydrogenase catalyzes: | a fast re-oxidation of NADH (H+) coenzyme for glyceraldehyde-3-phosphate
dehydrogenase enzyme can continue glycolysis in cells without mitochondria and in other
eukaryotic cells until O2 supply allows pyruvic acid to transfer into mitochondria |
| The statement about glucose degradation to lactic acid is correct: | all previous answers are correct
a. it is also called anaerobic glycolysis because it takes place without the participation of
oxygen;
b. the enzymes involved in the stages of this process are localized in the cytoplasm;
c. it takes place with great intensity in the first stages of effort in the skeletal muscle;
d. when large amounts of lactic acid are accumulated in the cell, the pH drops and this leads
to inhibition of the enzymes involved in glycolysis |
| Which of the following compounds is involved in H transfer from the reduced coenzymes
resulting from cytoplasmic glucose degradation in the mitochondria: | glycerol-3-phosphate |
| The 2-deoxyglucose compound is: | substrate for the hexokinase enzyme, following the action of which it is formed an ester
which is not a substrate for the next enzyme in glycolysis, the process thus being blocked; |
| Which of the following statements is correct: | arsenites and arsenates replace phosphoric radicals in ATP formation, causing an energy
collapse of cells |
| The reaction is given:
A + NAD + + CoA-SH → CH3 - CO- S-CoA + B + CO2
Compound A of the above reaction is: | pyruvic acid; |
| Compound B in the reaction from item 15 can be: | reduced nicotinamide dinucleotide |
| The enzyme that catalyzes the reaction from item 15 is: | pyruvate dehydrogenase |
| Acetyl-CoA is not a precursor for biosynthesis: | phosphoenolpyruvic acid |
| Which of the the statement about the pentose phosphates pathway is correct: | it leads to the formation of NADPH (H +) |
| About glycolysis it is correctly to say that: | it is a sequence of catabolic reactions that take place in the cytosol |
| The process by which lactic acid is metabolized is called: | gluconeogenesis |
| The correct statement about the Cori Cycle is: | a) it ensures the metabolism of lactic acid resulting from glycolysis;
b) it contributes to the prevention of lactic acidosis;
c) it ensures the reuse of lactic acid;
d) it realizes transport of the lactic acid to the liver;
all the above answers are correct |
| Because the reduced NADH (H +) coenzyme resulting in cytosol from glycolysis cannot
penetrate into the mitochondria, only the transfer of hydrogen to the inner mitochondrial
membrane is ensured. Which of the following compounds is involved in this transfer: | all the mentioned compounds are involved, ensuring the transfer of hydrogen to the
coenzyme FAD. |
| The reduced coenzyme NADH2 results from the reaction catalyzed by: | hydroxyacyl CoA-dehydrogenase |
| Under the action of cytoplasmic lipases, triacylglycerols are hydrolyzed in glycerol and
fatty acids. The destination of the resulting glycerol may be as follows: | depending on the needs of the cell, respectively of the body, glycerol can be used by any of
the mentioned metabolic pathways |
| Carnitine is a compound that facilitates the transfer of: | fatty-acyl-CoA in mitochondria |
| The number of reduced NADH (H+) coenzymes resulting from the 4 reactions of β-
oxidation by 1 mole of butyric acid (C4) is: | 1 reduced NADH (H +) coenzyme |
| The number of reduced FADH2 coenzymes resulting from β-oxidation of 2 moles of
butyric acid (C4) is: | 2 reduced FADH2 coenzymes |
| The number of moles of acetyl-CoA resulting from β-oxidation of 3 moles of butyric acid
(C4) is: | 6 moles |
| The energy balance (in the form of ATP) resulting from the complete degradation of 2
moles of butyric acid (C4) is: | 56 moles ATP |
| Propionyl-CoA cannot result from: | β-oxidation of palmitic acid (C16) |
| Excessive acetyl-CoA production occurs in the following situations: | excess of acetylCoA results in any of the situations presented above |
| The process by which excess of acetyl-CoA is transformed into acetyl acetic acid, β-
hydroxybutyric acid and acetone is called: | ketogenesis and occurs in the hepatocyte mitochondria |
| The statement about β-hydroxybutyric acid is incorrect | by oxidation / dehydrogenation leads to lactic acid |
| About malonyl-CoA the statement is correct; | is intermediate in the cytolplasmatic biosynthesis of fatty acids |
| The pathway of fatty acid biosynthesis by elongation is located in: | mitochondrial matrix |
| The metabolic pathways of fatty acid biosynthesis, although located in distinct subcellular
compartments, both the malonyl-CoA pathway and the elongation pathway, go through a
similar sequence of reactions, acylation, reduction, dehydration, reduction. What is coenzyme
used in both metabolic pathways | NADPH (H +) |
| For glyceride biosynthesis it is used: | all the mentioned compounds are necessary |
| Coenzyme NADPH (H +) is required for the functioning of the following dehydrogenases: | acyltransferase |
| What is the particular feature common to the enzymes α-glycerol kinase, hexokinase,
pyruvate carboxylase | catalyzes reactions resulting from ATP consumption; |
| Which of the following enzymes is involved in gastric protein digestion: | pepsin |
| The transformation of pepsinogen, the inactive precursor of pepsin, into the active
enzyme, takes place under the action of: | hydrochloric acid |
| Which of the following hydrolytic enzymes is biosynthesized as an inactive precursor,
called proenzyme or zymogen: | elastase |
| After being subjected to hydrolysis under the action of proteases in the stomach, intestine
and cells of the intestinal mucosa, the proteins are absorbed as: | amino acids |
| The intracellular hydrolysis of endogenous proteins is correct: | a) is a highly specialized process, localized in lysosomes and proteasomes;
b) it is necessary for the replacement of used proteins
c) it is necessary for the replacement of proteins that have not been properly synthesized,
either from the point of view of the primary structure (replacement of one or more amino
acids) or of the secondary, tertiary and / or quaternary structures;
d) plays an important role in controlling the cell cycle evolution, including the initiation of
apoptosis;
e) all the above answers are correct |
| The labeling of the proteins to be degraded at the level of the proteasomes is done by
binding to: | ubiquitin |
| The oxidative deamination of the amino acid alanine (CH3-CH (NH2) -COOH) results in: | pyruvic acid (CH3-CO-COOH), together with ammonia |
| The statement regarding biogenic amines is incorrect: | can be used as precursors in gluconeogenesis |
| Glutamate pyruvate transaminase (GPT) also called Alanin-aminotransferase (ALT) and
Glutamat-Oxaloacetat-Transaminase (GOT) also referred to as Aspartat-aminotransferase
(AST) are enzymes of the transaminase class, also used in clinical diagnosis. The coenzyme
of these enzymes is: | pyridoxal phosphate |
| Transamination is a complex process of amino acid degradation and biosynthesis, which
makes the connection between protein metabolism and the tricarboxylic acid cycle (Krebs),
glycolysis, urea cycle. The couple of compulsory compounds present in any transamination is: | glutamic acid / α-ketoglutaric acid |
| Which of the following compounds is not part of the urea cycle: | glycine |
| The urea cycle takes place in: | hepatocytes |
| Carbamoyl phosphate results from condensation of ammonia with the bicarbonate anion
which is the form of CO2 transport. About this compound the statement | the enzyme that catalyzes the reaction of formation of this compound is called carbamoyl
phosphate synthetase |
| The form of ammonia elimination in birds is: | uric acid |
| Which of the following metabolic processes does not require, for initiation, consumption | tricarboxylic acid cycle (Krebs) |
| The scheme is given:
(1)
2-phosphoenolpyruvic acid + A B + ATP
(2) ↓ + ATP + HCO3 –
C
Compound B in the above scheme is | pyruvic acid; |
| Compound C in the above scheme is: | oxalylacetic acid; |
| The enzyme that catalyzes the transformation of A into C is: | pyruvate carboxylase |
| About the reaction (1) from item 56 the correct statement is: | is a cytoplasmic reaction |
| About the reaction (2) from item 56 the correct statement is : | is an anaplerotic reaction |
| Point mutations affect | answers a and d are correct
three-dimensional conformation of polypeptide chains
one of the nitrogenous bases of a codon, resulting in a modified codon, which causes the
insertion of another amino acid in the polypeptide chain |
| The intoxication of animals with organophosphorus compounds is due to: | the inhibitory action of these compounds on the acetylcholinesterase enzyme, which causes
the accumulation of acetylcholine |
| Glycogenoses are metabolic diseases with genetic determination. The gene that may
undergo mutations leading to dysfunctional enzymes is: | the answers "a", "b" and "d" are correct
glucose-1-phosphatase
pyrophosphorylase
the branching enzyme |
| Metabolic correlations between carbohydrates and lipids cannot be established through: | glycine |
| Choose the correct answer regarding gluconeogenesis: | answers "c" and "d" are correct
is a process localized in hepatocytes by which glucose is biosynthesized from noncarbohydrates precursors (lactic acid, glycerol, glucose generating amino acids)
is the process of glucose obtaining from glycogen |
| Which of the following compounds are located in the inner mitochondrial membrane: | all the mentioned compounds |
| The metabolic pathway in which the compounds chosen in the previous item is called: | electron transport chain |
| Which of the following physiological conditions can lead to intensification of urea cycle
which results in increased uremia: | answers "a" and "c" are correct
high protein diet
starvation |
| Ubiquinone or coenzyme Q is | the only non-protein component of the electron transport chain; |
| Tyramine comes from the amino acid tyrosine following a process of: | decarboxylation |
| The correct statement regarding ornithine is: | is a diamino monocarboxylic amino acid involved in urea cycle |
| Hexokinase is: | the enzyme that catalyzes the first reaction of glycolysis |
| Fructose-6-phosphate is: | all the above answers are correct
a phosphoric ester of fructose
a metabolite in glycolysis
an intermediary in the pentose phosphate pathway
an intermediary in the metabolism of sucrose |
| The complete degradation of 2 moles of pyruvic acid results in: | 30 moles of ATP |
| The glutamic acid is transformed, by a transamination reaction, into α-ketoglutaric acid,
which may enter the tricarboxylic acid (Krebs) cycle. The number of NADH (H +) coenzymes
resulting from 3 moles of α-ketoglutaric acid that travel this metabolic pathway is: | 6 moles |
| Oxalylacetic acid (oxaloacetate) coupled with acetyl-CoA forms the first intermediate in
the tricarboxylic acid (Krebs) cycle. This is called: | citric acid (citrate) |
| Oxalylacetic acid is formed from the reaction: | answers "b" and "c" are correct
aspartic acid with α-ketoglutaric acid, under the action of the aspartate-aminotransferase
enzyme
pyruvic acid with bicarbonate anion, with consumption of ATP, under the action of the
enzyme pyruvate carboxylase |
| Glycogenin is: | protein involved in glycogenogenesis |
| It is an endergonic process: | both, urea cycle and gluconeogenesis are endergonic processes |
| Choose the correct statement | the statements "a" and "d" are correct.
fatty acids with less than 12 carbon atoms in the molecule are absorbed directly through the
intestinal mucosa degradation of fatty acids resulting from the cytoplasmic hydrolysis of glycerides takes place, as does glycolysis, in the cytoplasm |
| The complete degradation of 2 moles of stearic acid, (C18) produces: | 294 moles of ATP |
| From β-oxidation of 3 moles palmitic acid (C16) results: | 21 moles FADH2 |
| The reaction is given:
R-COOH + ATP + X → Y + AMP + PPi
Choose the incorrect statement about this reaction: | compound X is acetyl-CoA |
| The translocase is: | the enzyme involved in the transfer of the activated fatty acids through the internal
mitochondrial membrane |
| Transketolase and transaldolase are: | enzymes that function coupled to the shunt of the pentosophosphates |
| The statement of the Pentose Phosphate Pathway is incorrect: | leads to the formation of a large amount of NADP + |
| Acetyl-CoA is a precursor for biosynthesis of: | stearic acid |
| The highest amount of energy in form of ATP is obtained from: | complete degradation of one mole of lauric acid (C12) |
| Which of the following intermediate metabolites cannot be transformed into amino acids: | butyric acid |
| The following statement about aldolase is incorrect: | is a hydrolase |
| The reaction below is catalyzed by an enzyme that has as coenzyme pyridoxal phosphate,
a derivative of vitamin B6:
A + B↔C + D
The correct statement about this reaction is: | all the above statements are correct
if A is glutamic acid and B is pyruvic acid, then C is α-ketoglutaric acid and D is alanine;
if A is glutamic acid and B is oxalylacetic acid, then C is α-ketoglutaric acid and D is
aspartic acid;
if the answer "a" is correct, then the enzyme is called glutamate-pyruvate transaminase
(GPT) or alanine aminotransferase (ALT);
if the answer "b" is correct, then the enzyme is called glutamate-oxalylacetate transaminase
(GOT) or aspartate aminotransferase (AST) |
| The statement about acetyl acetic acid is incorrect: | is a precursor for alanine biosynthesis |
| The statement regarding the compound HOOC - CH2 - CH2 - CO - S - CoA is incorrect | results from the deamination of aspartic acid |
| Oxidative phosphorylation is located in: | internal mitochondrial membrane |
| Enoil-CoA hydrase is an enzyme involved in: | the answers "a", "b" and "c" are correct
β-oxidation of fatty acids with an even number of carbon atoms in the mitochondria
β-oxidation of long-chain fatty acids in peroxisomes |
| It is not part of the isomerase class | the enzyme that catalyzes the conversion of glyceraldehyde-3-phosphate into 1,3-
diphosphoglyceric acid |
| Which of the following compounds is not intermediate in the tricarboxylic acid (Krebs)
cycle: | acetyl-CoA |
| Pantothenic acid or vitamin B5 enters the structure: | answers "a" and "d" are correct
the acyl-acyl carrier protein (ACP) carrier group
coenzyme A |
| About pyruvic acid the following statement is incorrect: | by decarboxylation it is transformed into oxalylacetic acid, anaplerotic reaction of
supplying the tricaboxylic acid (Krebs) cycle with intermediates |
| Which of the following compounds is not a macroergic compound: | GPT |
