- How many isoenzymes of lactate dehydrogenase exist and in which tissues they prevail?
a.3 - LDH1- Heart LDH5 – muscle, liver LDH3 – growth, cancer
- Write the part of FAD molecule which is responsible for it's reduction properties.
a.On 2 nitrogens (number 1,5) of the riboflavin ring
- Give an example of multienzyme complex and explain the principle of it's function.
a.Pyruvate dehydrogenase complex, converts pyruvate to acetyl-CoA, multienzyme means several enzymes that catalyzes successive steps in a series of reactions which are associated together as a complex, also: fatty acid synthase complex
- What is the net production of ATP in glycolysis (under aerobic conditions) – including CAC and respiratory chain?
a.38(36) ATP : 2 at substrate level, 6(4) from NADH(dependant on transport system to mitochondria), 6 from NADH (pyruvate dehydrogenase complex), 24 from CAC
- The 3rd NADH production in Kreb's cycle involves the reaction of?
a.Malate ------ oxaloacetate (by malate dehydrogenase)
- What is glycogenolysis? How is it regulated?
a.The breakdown of glycogen into it's bulding blocks – glucose, glucose-1-P in order to replenish glucose supply in blood, regulated by hormones (glucagon, epinephrine) which modify (by phosphorylation) enzymes, in this way – can stimulate or inhibit it.
- Which hormones play an active role in glycogen synthesis?
a.Insulin
- How is called the degradation of fatty acids, and why?
a.β-oxidation, because the oxidation occurs on the β carbon of the fatty acid chain.
- The compound known as ACP which means…. And it participates at….
a.Acyl carrying protein, fatty acid synthesis (by transport of acyl groups)
- Name the rate controlling enzyme in cholesterol biosynthesis.
a.HMG-CoA reductase
- Very important products of uronic acid pathway are?
a.Glucoronic acid, UDP-glucoronate
- Gout is the disease cause by the disorder in the metabolism of?
a.Purines (uric acid accumulates because of a partial deficiency of HGPRT)
- Purine base adenine is degraded by xanthine oxidase to? Give all 3 intermidiates.
a.Adeninehypoxanthinexanthineuric acid
- In which part of cells are located receptors for testosterone and progesterone?
a.In the cytosol, or the nucleus
- Where are located receptors for polypeptide hormones?
a.On the cell membrane
- Thyroxine (T4) is a derivative of the AA (Give structure)?
a.
- Explain the principle of immunoelectrophoresis
a.Separation of proteins by charge and their reaction with antibodies
- Which immunoglobulins contain the J-chain?
a.IgM, IgA
- Which compounds can act as Ag?
a.Polysaccharides, proteins
- What is the most frequent conjugation reaction?
a.With UDP-glucoronate
- Which nutrients are absorbed by ileum?
a.Water, bile acids, B12, electrolytes
- Describe the principle of creatinine determination and name the reaction.
a.JAFFE reaction, picric acid (in alkaline medium) gives orange color, then messure by spectrophotometry
- Write the reaction for the determination of chloride conc. In blood serum
a.Chloride is titrated with mercury (II) nitrate
- What is the principle of the cholesterol determination in biological material
a.Concentrated sulfuric acid acetoanhydrate gives green-blue color, the spectrophotometry
- Transducin is? And it is active in?
a.G-protein, stimulation of rhodopsin, taste buds
- ATP molecule is composed of?
a.Adenine, Ribose, 3 phosphates
- Pantothenic acid forms a part of a compound which is named?
a.CoA
- Write the coordination number and oxidation number of Fe in Hb.
a.6, 2
- Write the reaction of CAC in which ATP is produced on the substrate level.
a.+CoA
- Write the initial reaction of Kreb's cycle which is catalyzed by the citrate synthase.
a.
- 6-phospoglucono-δ-lactone is produced in the pathway which is named?
a.Pentose phosphate pathway
- β-glycosidase (lactase) is specific for splitting of?
a.Lactose (galactose+glucose)
- Explain the principle of facilitated transport across membranes.
a.The conformational change of the channel when it is approached by the molecule (not energy dependant, "ping-pong" mechanism)
- Phosphatidic acid is the precursor in the synthesis of triacylglycerols, write the chemical structure.
a.
- What is the fate of glycerol that has been released in degradation of lipids?
a.Gluconeogenesis or TAG synthesis
- Write the reaction in fatty acid biosynthesis which leads to formation of malonyl Co-A.
a. (by acetyl-CoA carboxylase)
- Explain the term enterohepatic circulation.
a.The releasing of the bile acids and salts and bilirubin into the small intestine, their reabsorbtion to the blood and their return to the liver.
- Describe the metabolic pathway of histidine degradation (without enzymes)
a.Histidineα-ketoglutarate
- Name precursors required for biosynthesis of pyrimidine nucleotides.
a.CO2 + glutamine + aspartate
- Name 2 hormones of amine character.
a.Insulin, glucagon, epinephrine
- Parath hormone regulates?
a.Level of ca2+ in the blood (increases)
- What is the difference between polyclonal and monoclonal antibodies?
a.Polyclonal – made from multiple genes, monoclonal – one gene
- Where do biotransformation enzymes take place?
a.Cytochrome P450 (Endoplasmic reticulum)
- Aliphatic hydrocarbon xenobiotics is converted in the phase I by hydroxylation to?
a.Aliphatic alcohols
- Describe 3 transport proteins.
a.Albumin, transferin, lipoproteins, hemoglobin
- What are haptens?
a.Small molecules not acting as antigens
- What reagent you can use for the glucose test in the urine? Explain.
a.Fehling test – giving red color (change from blue) in boiling water if glucose is present
- Give roles of saliva.
a.Digestion, moisturizing, immunity, lubrication, increases pH, cleaning of teeth
- Name coenzyme that transfer one carbon units.
a.THF – tetrahydrofolate, SAM- s-adenosylmethionine
- Name the reaction for detection of bile pigments in urine.
a.Ehrlich reaction
- At which part of NAD⁺ molecule is hydrogen bound? Draw the structure.
a.At carbon number 4 of the niacin ring
- Formation of succinate in Kreb's cycle is associated with energy production in the form of? Give the reaction.
a.GTP. +CoA +GTP (succinate thiokinase)
- Oxidative decarboxylation of pyruvate results in formation of?
a.Acetyl-CoA
- Uronic acid pathway serves mainly for?
a.UDP-glucoronate (xentobiotic, bilirubin conjugation), glycoproteins
- α-glucosidase (maltase) is responsible for splitting of? And it belongs to the enzyme class?
a.Maltose = Glucose+glucose. 3 - hydrolases
- What is energetically more efficient? Aerobic or anaerobic glycolysis? Why?
a.Aerobic, because it utilizes the respiratory chain and CAC for production of additional ATP (energy)
- In which part of the cell fatty acid oxidation and lipogenesis take place?
a.Degradation – mitochondria, lipogenesis – cytosol
- Which hormones stimulate and inhibits lipogenesis?
a.Stimulates – insulin, inhibits – glucagon
- What is the common precursor for synthesis of TAG?
a.Glycerol-3-P
- Give AA which are metabolized through fumarate.
a.Phenylaalanin, tyrosine
- Chaperons (or HSP) are responsible for?
a.Folding of proteins
- Enkephalins and endrophins are considered to be…? And are produced in?
a.Hormones produced in GIT and brain
- What is the role of cGMP in the visual process?
a.Second messanger
- Give the classes of immunoglobulins
a.IgM, IgE, IgA, IgG, IgD
- What is the function of variable and hypervariable part on immunoglobulins?
a.Determines specificity towards Ag (binds the Ag)
- The phase I is also known as? And it involves the reactions…?
a.Biotransformation, reaction of hydroxylation
- Give the main biochemichal function of kidney
a.Filtration of blood, synthesis of hormones – rennin, erythropoetin, compounds – creatine
- Why viruses can start the cancer process? Explain the biochemical mechanism?
a.They insert their own DNA to the DNA of the host, causing a mutation which can lead to excessive transcription of genes
- Ehrlich reaction is used for detection of?
a.Bile pigments (bilirubin) in urine
- Explain the biochemical principle of "mad cow" disease.
a.Prions – proteins which are able to multiply, accumulate in brain damaging tissue
- Rhodopsin is……………..? And it functions as………..…?
a.Visual pigment in retina, functions as transfer of signal
- Give the principle of deoxyribonucleic protein isolation from spleen.
- Name the conditions which mainly affect the rate of enzymatic reactions.
a.pH, temp, pressure, conc. Of enzyme, conc. Of substrate
- What is the relationship between the activity of enzyme and Kmvalue?
a.if Km value is high the activity of the enzyme is slow because it's affinity towards it’s substrate is low, if Km is low then the opposite
- Give the enzymes which need emulgator for their activity, explain the mechanism.
a.Lipases, lipases catalyzes the breakdown of lipds (which are not soluble in water) that's why the need the emulgators to make them water soluble.
- The anapleurotic reactions are…………………?
a.Reactions that can give the intermediates of the CAC (e.g: carboxylation of pyruvate to oxaloacetate)
- Give 2 inhibitors of the respiratory chain and explain which reactions the affect.
a.Pieridicine A (inhibits complex I), oligomycin (inhibits ATP synthase complex)
- In which metabolic pathway are required branching and de-branching enzymes?
a.Glycogen synthesis and degradation
- Glycolysis is regulated by 3 enzymes, what are they?
a.Hexokinase (glucokinase), fructose-6-P kinase, pyruvate kinase
- The enzyme monoacyleglycerol acyltransferase takes part in the process…
a.TAG synthesis
- How many moles of ATP are released during the degradation of 1 mole of plmitic acid?
a.129 ATP: 8X12 (acetyl-coA) = 96, FADH2X7 = 14, NADHX7 = 21, -2ATP (transport + malonyl-coA making)
- Ketogenesis produces compounds (structures)……..…. Which can be utilized as………?
a.Ketone bodies:.
Are utilized for energy during starvation.
- Cytoplasmic acyl-CoA coming from…………. Is transferred through mitochondrial membrane as……….. and cleaved to acetyl-CoA in the reaction of……………….?
a.TAG degradation, carnitine, β-oxidation
- In which parts of the cell is urea synthetized? Give all related metabolites.
a.Mitochondria, cytosol.
- Explain the role of cAMP in the hormone signal transduction.
a.cAMP is a second messanger formed when the G-protein interacts with the membrane bound enzyme adenylate cyclase. It activates a family of enzymes called protein kinase A, which in turn phosphorylate other enzymes making them active or inactive.
- The main reaction involved in the phase I of xenobiotic metabolism is?
a.Hydroxylation
- Explain the relationship between oncogenes and cancer.
a.Are viruses that act directly on DNA (inserting their own DNA) and induce mutation that leads to cancer.
- Water excertion through the kidney is controlled by?
a.ADH (anti duaretic hormone) secreted from the hypophysis.
- Which enzyme and proteins are involved in the mineralization of bones?
a.Alkaline phosphatase, osteocalcin, osteonectin
- The blood glucose range in fasting healthy adults is?
a.3-6 mmol/L
- Draw the schematic structure of IgG molecule and name the individual part.
a.
- Give the main components of plasma proteins, what method is used for their separation?
a.Albumins, globulins: α1, α2, β, γ. Electrophoresis is used for separation.
- The uffelmann reagent serves for detection of…… Which is the product of metabolism of………?
a.Lactic acid, anaerobic glycolysis (coming from pyruvate)
- The examination of GGT activity in blood serum is of great clinical importance, why?
a.Detection of liver damage – alcohol intoxication, cirrhosis.
- How many ATP are produced during aerobic and anaerobic glycolysis?
a.36 or 38 (depending on shuttle) in aerobic, 2 in anaerobic
- Which reactions of glycolysis are not reversible for gluconeogenesis?
a.Glucoseglucose-6-Pfructose-6-Pfructose 1,6-bisphosphat PEPpyruvate
- The pentose phosphate pathway serves for?
a.Production of NADPH (for fatty acid synthesis) and ribose-5-P (for nucleotide synthesis)
- Which nucleotides are involved in synthesis of glycogen?
a.UTP, ATP, cAMP
- In which organ is glycogen stored?
a.Liver, muscle
- Which glycosidic bond forms branches in glycogen?
a.α 16
- Which hormones are involved in glucose level regulation?
a.insulin, glucagon, epinephrine, cortisol
- Give diseases related to sugar metabolism?
a.Diabetes mellitus, fructosuria, lactose intolerance, von gierke's disease, pomp's disease
- How is transferred NADH formed in the cytosol during glycolysis into the mitochondria?
a.2 shuttles: malate-aspartate shuttle (no loss of ATP), 3-P-glycerate shuttle (converted to FADH2 – loss of 1 ATP)
- Write the first reaction of glycolysis.
a.Glucose + ATPglucose-6-P + ADP (hexokinase, glucokinase)
- Sulfated glucoseamine is present in the polysaccharide……?
a.Heparin
- 2,3-bisphosphoglycerate is formed in red cells, what is it's role?
a.No production of ATP, helps hemoglobin to release oxygen to tissue
- Write the last reaction of glycolysis in the cytosol.
a.Aerobic: (pyruvate kinase). anaerobic: (LDH)
- Describe the cori cycle and it's function.
a.During intensive muscle work (anaerobic conditions), the lactic acid formed in muscle is transported via blood to the liver, then converted back to pyruvate (by LDH5) and used for gluconeogenesis, then the glucose formed is transported back to muscle for glycolysis.
- 6-phosphogluconate-δ-lactate is produced in……?
a.Pentose phosphate pathway
- NADPH is synthesized mainly in…….?
a.Pentose phosphate pathway
- Which intermediates are characteristic for metabolism of galactose?
a.UDP-galactose, galactose-1-P
- Which derivatives of glucose play an important role in detoxification process?
a.Glucoronic acid, UDP-glucoronate
- Glycogen phosphorylase catalyzes ……..?
a.The degradation of glycogen (breaking of the α 14 bonds)
- Write the formula of 1,3-bisphosphoglycerate and give it's metabolic role.
a.It is an intermediate of glycolysis and gluconeogenesis:
- Write the reaction of glycolysis catalyzed by aldolase.
a.
- Write the reaction of uridine diphosphate glucose formation.
a.UTP + Glucose-1-PUDP-glucose + PPi (UDP-Glucose phosphorylase)
- Which hormones are involved in metabolism of glycogen?
a.Insulin, glucagon, epinephrine
- Give the major metabolic pathways for glucose utilization.
a.Glycolysis, glycogen synthesis, penoste phosphate pathway
- Write the reaction of alcoholic fermentation starting with pyruvate.
a.
- The common intermediates of glucose and fructose metabolism are?
a.Fructose-6-P, fructose-1-P, glyceraldehyde-3-P
- Chitin contains the sugar unit with the name…………..?
a.N-acetyleglucoseamine
- Describe glucose-alanine cycle and it's role.
a.Is during starvation, provides an efficient mechanism for muscle to dispose of nitrogen and achive energy (in the form of glucose) for work:
- Which and how many nucleotides are involved in gluconeogenesis?
a.6ATP (2 of them GTP)
- Give the principle steps in biosynthesis and β-oxidation of fatty acids.
a.Synthesis: 1)export of acetyl-coA to cytosol 2)formation of malonyl-coA 3)reduction 4)dehydration 5) reduction. Degradation: 1)transport of fatty acyl-coA into mitochondria (by carnitine) 2) oxidation 3)hydration 4)oxidation 5)removal of acetyl-coA
- Give the role of carnitine in the β-oxidation of fatty acids.
a.Transport of fatty acyl-coA from cytosol into mitochondria.
- Give the initial step in cholesterol synthesis.
a.Formation of acetoacetyl-coA (acetyl-coA + acetyl-coAacetoacetyl-coA + coA)
- Which compounds are synthesized from cholesterol?
a.Steroid hormone, bile acids, vitamin D
- Give the initial compounds and pathway for production of prostaglandins.
a.Arachidonic acid [20:4(5,8,11,14)], cycloxygenase pathway
- Give the initial compound and pathway for production of leukotrienes.
a.Arachidonic acid [20:4(5,8,11,14)], lipoxygenase pathway
- Give forms in which cholesterol is excreted from the body.
a.Bile acids, cholesteryl esters
- Give at least 2 coenzymes taking part in β-oxidation of fatty acids.
a.NAD+, FAD+, FMN, coA
- Which compound is a donor of H+ in biosynthesis of fatty acids?
a.NADPH
- Give the active form of choline in synthesis of phospholipids.
a.CDP-choline
- Ceramide is composed of…………………….?
a.Sphingosine + fatty acid
- Give the main functions of lipoproteins.
a.Transport of lipids (TAG, cholesterol, cholesteryl esters)
- Give the first step in β-oxidation of fatty acids.
a.Dehydrogenation (oxidation)
- Explain, what is ACP (acyl carrying protein)?
a.A protein that carries the acyl groups during synthesis of fatty acids (coenzyme in fatty acid synthase complex)
- Give the names and formulas of the ketone bodies.
- Give the differences in the activities of phospholipase A1,A2, C and D.
a.A1 – cleaves the primart fatty acid. A2 – cleaves the secondary fatty acid. C – cleaves phosphoalcohol. D – cleaves only alcohol. (phospholipids)
- Give the fatty acid participating in formation of cholesterol esters.
a.Palmitic acid (16:0), stearic acid (18:0), oleic acid [18:1(9)]
- Give the substrate and product of lipogenesis and part of the cell where it takes place.
a.Acetyl-CoA, Palmitic acid – cytosol
- Give the name of fatty acid catabolic process and the reason.
a.β-oxidation , because oxidation occurs on the β carbon of the fatty acid chain
- β-oxidation with an odd number of C atoms gives acetyl-CoA and……………….?
a.Propionyl-coA
- Give the composition of lecitins.
a.Lecitine (phosphatidylcholine) = choline +Phosphatidic acid (diacylglycerol 3-P)
- Give the end product of triacylglycerol digestion.
a.MonoacylGlycerol + 2 fatty acids
- What is a micelle?
a.Mix of lipids with bile salts that are soluble (amphipathic) and can pass to the cells.
- What is sphingosine?
a.Unsaturated aminoalcohol (unsaturated FA attached to an aminoalcohol)
- What are chylomicrons?
a.Lipoprotein that is reasponsible for transport of TAG (lowest density lipoproteins)
- Lanosterol is an intermediate in synthesis of?
a.Cholesterol
- What kind of energy does drive the ATP synthesis?
a.Electrochemical gradient
- Give two examples of commercial use of enzymes
a.Washing powder, food industry
- Complete the reaction, sucrose + water (sucrase) =
a.Glucose + fructose
- The compound 2,3-bisphosphoglycerate is formed in erythrocytes, what role does it play?
a.No production of ATP, enabling hemoglobin to better release oxygen
- Asp and Asn enter the CAC in the form of?
a.Oxaloacetate
- Name 3 steps of energy conservation in the living body.
a.Glycolysis, CAC, β-oxidation, respiratory chain
- Which reactions in glycolysis are irreversible?
a.Glucoseglucose-6-P, fructose-6-Pfructose-1,6-bisP, PEPpyruvate
- Give the diseases (4) related to sugar metabolism
a.Diabetes mellitus, fruktoseuria, galactosuria, lactose intolerance
- Pepsin belongs to the enzyme class (the name and the number):
a.Hydrolases class III
- Give the reaction of CAC at which GTP(ATP) is produced:
a.+ CoA +GTP (succinate thiokinase)
- Which complexes and enzymes are in the respiratory chain?
a.Complex I(point of entry from NAHDH – NADH dehydrogenase), II(point of entry from FADH2 – succinate dehydrogenase), III (cytochrome c reductase), IV(cytochrome c oxidase), V(ATP synthase)
- β-oxidation of fatty acids with odd number of carbon leads to:
a.Acetyl-CoA, Propionyl-coA
- Explain the term "feedback inhibition"
a.Inhibition of the enzyme by the product of the reaction (or one of the following reactions)