Topic list

  • Practical questions
  • Carbohydrates (metabolic integration)
  • Lipids (metabolic integration)
  • Amino acids-nucleotides
This list is aimed to help you get prepared for the semi-final examinations and serves as a collection of potential quetions for midterm examinations
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Practical questions


  • Competitive inhibition of succinate dehydrogenase by malonate
  • Mitochondrial oxidation I.: Experimental conditions for determination of oxygen consumption by intact mitochondria. Definition and experimental measurement of P/O ratio.
  • Mitochondrial oxidation II.: Please draw the curve of mitochondrial oxygen consumption after consecutive addition of glutamate/malate – ADP – atractylozide – DNP – oligomycin – CN-. Explain the curves briefly.
  • Isoenzymes: pyruvate kinase
  • Digestion of lipids, determination of lipase activity
  • Measurement of blood plasma cholesterol and triacylglycerol
  • Purification of trypsin by affinity chromatography and substrate specificity of trypsin and chymotrypsin

Bioenergetics

  1. Group transfer potential. Coupled reactions in the metabolism.
  2. The phosphoryl transfer. Role of high energy phosphates in the intermediary metabolism. ATP.
  3. Formation of acetyl CoA from pyruvate. The pyruvate dehydrogenase complex. Regulation of the pyruvate dehydrogenase.
  4. Reactions of citric acid cycle. Enzymes and coenzymes.
  5. Localization, regulation and significance of citric acid cycle.
  6. Glycolysis. 1st phase.
  7. Glycolysis - 2nd phase.
  8. Mitochondrial membranes and their permeability. Mitochondrial transporter systems.
  9. The respiratory chain: components, organization, function, inhibitors.
  10. Respiratory control, P/O ratio, uncoupling of oxidative phosphorylation.
  11. Mitochondrial ATPase. (FoF1-ATP-ase): structure, function, inhibitors. Mechanism of oxidative phosphorylation. Chemiosmatic hypothesis.
  12. Oxidoreductases - classification, general characteristics. Redox cycles of the coenzymes, NAD, NADP, FAD, glutathion.
  13. Mitochondrial transport of reducting equivalents. Energetics of the complete oxidation of glucose.

Carbohydrates (metabolic integration)

  1. Major carbohydrate components of food. Their digestion and absorption. Lactose intolerance.
  2. GLUT family glucose transporters (localization, special characteristics and role).
  3. The pathway and importance of anaerobic glycolysis. Major lactate producing cells and tissues.
  4. Glucose phosphorylation. Its role in the metabolism of the cell. The different regulation of the isoenzymes.
  5. Hormonal and allosteric regulation of glycolysis in the liver.
  6. Energetics of aerobic and anaerobic glucose catabolism. Metabolic efficiency, participation of oxidative and substrate-level phosphorylation.
  7. Molecular mechanism and metabolic rationale of Pasteur-effect.
  8. Which non-carbohydrate precursors can be converted to glucose, in which organs and how?
  9. Compartmentation of gluconeogenesis. The glucose-6-phosphatase system and von Gierke's disease.
  10. Hormonal and allosteric regulation of gluconeogenesis in the liver.
  11. The importance of the different regulation of pyruvate kinase isoenzymes in liver (PK-L) and muscle (PK-M). Other points of coordinating the hepatic glycolysis and gluconeogenesis.
  12. Hepatic metabolism of fructose. The regulatory/toxic effects of fructose-1-phosphate.
  13. What is the fate of fructose in essential fructosuria? Metabolic consequences of fructose intolerance. What is the pathomechanism of hypoglycemia and hyperuricemia in hereditary fructose intolerance?
  14. Entry of galactose into the glycolytic-gluconeogenetic pathway. Galactose intolerance.
  15. UDP-galactose production from glucose in extrahepatic tissues. The role of UDP-galactose. Localisation, structure and function of lactose synthase.
  16. The oxidative branch of pentose-phosphate pathway. Its special role in the "biological oxidation" and its regulation.
  17. The non-oxidative branch of pentose-phosphate pathway. The co-operation of the two branches in various conditions.
  18. The mitochondrium-dependent and mitochondrium-independent NADPH production. The most important NADPH  consuming reactions. Drug-induced hemolytic anemia.
  19. The pathway of glycogenesis from glucose. Glycogenin.
  20. The pathway of glycogenolysis to glucose. Glycogen storage diseases.
  21. Hormonal and allosteric regulation of hepatic glycogen metabolism.
  22. Hormonal and allosteric regulation of glycogen metabolism in muscle.
  23. Comparison of the glycogen metabolism of liver and muscle (function, regulation).
  24. Role of key junctions in the regulation of metabolism. Glucose 6-phosphate.
  25. Role of key junctions in the regulation of metabolism. Pyruvate.
  26. The metabolism of red blood cells, muscle tissue and kidney.
  27. Biochemistry of the resorptive (well fed) state. a.) Metabolic interrelationship of tissues.
  28. Biochemistry of the resorptive (well fed) state. b.) Regulation of the main metabolic pathways in the liver.
  29. Biochemistry of fasting. a.) Metabolic interrelationship of tissues.
  30. Biochemistry of fasting. b.) Regulation of the main metabolic pathways in the liver.
  31. The Cori cycle.
  32. Regulation of the blood sugar level.
  33. The effects of glucagon in the metabolism.
  34. The metabolic effects of insulin.
  35. The biochemistry of diabetes.
  36. What is the mechanism of development of lactic acidosis in the absence of pyruvate-dehydrogenase activity? What further symptoms can be observed, if pyruvate-dehydrogenase deficiency is caused by the lack of lipoamide dehydrogenase subunit?
  37. What is the mechanism of brain damage detected in pyruvate carboxylase deficiency? Explain the development of hyperammonemia. Which metabolic pathways can be associated with the pyruvate-carboxylase function?
  38. What is the effect of physical exercise on the lactate concentration of venous blood coming from working muscles in normal subjects and in patients with McArdle's disease?


Lipids (Metabolic integration)

  1. Lipid-water interactions and their biological significance.
  2. Digestion and absorption of lipids.
  3. General rules of lipid transport. Structure and functions of major lipoprotein classes.
  4. Chylomicrons. Composition, formation, catabolism. Role of lipoprotein lipase.
  5. VLDL. Composition, formation, catabolism.
  6. LDL . Composition, metabolic fate. It's role in the transport of cholesterol. LDL receptors and familial hypercholesterolemia (type II.)
  7. HDL. Composition, metabolic fate. It's role in the transport of cholesterol.
  8. Storage and mobilization of triacylglycerols. Regulation of both processes.
  9. Transport of fatty acids through the inner mitochondrial membrane. Regulation of the transport.
  10. Beta oxidation of saturated fatty acids. The energetics of oxidation. Regulation of beta oxidation in the muscle and in the liver.
  11. Oxidation of unsaturated fatty acids and fatty acids with odd number of carbon atoms.
  12. Biosynthesis of saturated fatty acids.
  13. Regulation of fatty acid synthesis.
  14. Role of the adipose tissue in the carbohydrate and lipid metabolism.
  15. Synthesis and metabolic fate of ketone bodies. Regulation of synthesis.
  16. The physiological role of ketone bodies.
  17. Synthesis of cholesterol. Synthesis and importance of cholesterol esters.
  18. Regulation of cholesterol synthesis.
  19. Metabolism of the bile acids. Synthesis, regulation of synthesis, enterohepatic circulation. Clinical aspects.
  20. Role of key junctions in metabolism. Fatty acyl-CoA, metabolic fate, regulation.
  21. Regulation of trigliceride and phospholipid metabolism in the liver.
  22. The metabolism of brain. Metabolic properties of neurons and astrocytes.
  23. Reverse cholesterol transport, biochemistry of atherosclerosis.
  24. The role of carnitine. What forms and consequences of carnitine deficiency can be detected in humans?
  25. The function of lipoprotein lipase. How are lipoprotein lipase isoenzymes regulated in various organs and in various physiological conditions?


Amino acids and nucleotide metabolism

  1. Metabolism of proteins: nutritional requirements, deficiency states.
  2. Degradation of proteins in the gastro-intestinal tract I. Endopeptidases (zymogens, activation, substrate specificity).
  3. Degradation of proteins in the gastro-intestinal tract II. Exopeptidases and absorption of amino acids.
  4. L-glutamate dehydrogenase. The role of glutamic acid in the deamination of amino acids, transdeamination.
  5. The role of aspartate in the metabolism of N-containing compounds. Purine nucleotide cycle.
  6. Transamination. Mechanism, metabolic importance, the role of pyridoxal-phosphate.
  7. The transport of ammonia, the role of glutamine and alanine. Glutamine synthesis and the loss of the amide-group.
  8. Urea cycle. Reactions, regulation, metabolic disorders.
  9. Glucoplastic and ketoplastic amino acids: the metabolic intermediates produced from the carbon skeletons of amino acids.
  10. Amino acids forming pyruvate (mechanisms).
  11. Amino acids forming succinyl-CoA (mechanisms).
  12. Amino acids forming alpha-ketoglutarate and oxaloacetate (mechanisms).
  13. The catabolism of phenylalanine and tyrosine (main intermediates and enzyme defects).
  14. The role of methionine as a methyl group donor in biosynthetic reactions, the metabolism of methionine, synthesis of polyamines.
  15. The role of folate coenzymes in the metabolism.
  16. The synthesis of nonessential amino acids: serine, cysteine aspartate, alanine, glutamate.
  17. The „de novo" synthesis of ornithine and prolin.
  18. The metabolism of glycine. The synthesis of creatine.
  19. The biosynthesis of heme, regulation of heme biosynthesis.
  20. The catabolism of heme, formation and metabolism of bile pigments.
  21. The catabolism of sulfur-containing amino acids. The formation and metabolic importance of "active sulfate".
  22. Cytoplasmic and mitochondrial synthesis of carbamoyl phosphate.
  23. The sources of the constituent atoms of the purine ring. Synthesis and regulation of purine nucleotides.
  24. The structure and role of the active form of folic acid in the synthesis of nucleotides. The synthesis of thymidilate. The molecular basis of the actions of the antimetabolites of folic acid.
  25. The biosynthesis of pyrimidine nucleotides and its regulation in mammalian tissues.
  26. The biosynthesis and regulation of deoxyribonucleotides.
  27. Salvage reactions in the metabolism of purine nucleotides. The Lesch-Nyhan syndrome.
  28. The degradation of purine and pyrimidine nucleotides. Metabolic diseases in the catabolism of purines.
  29. The pathogenesis and consequences of hyperammonemias
  30. The effect of per os and parenteral administration of cyanocobalamin on the amino acid metabolism. Symptoms and their molecular background in vitamin B12 deficiency.


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