Biochemistry Best of Five Collection for Medical Students

7/27/2019 Biochemistry Best of Five Collection for Medical Students

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Biochemistry best of

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medical students

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CELL & WATER

in prokaryotic cells:not foundis1. The followinga) Cytoplasmic membrane

b) DNA

c) Cytoplasm

d) Nucleus

e) RNA

2. Buffers in the human body include:a) Carbohydrates

b) Phospholipids

c) Sulphuric Acid and Sulphate

d) Phosphoric Acid and Phosphate

e) None of the Above

3. Water is the ideal solvent in biological systems because of its:

a) Low melting pointb) Low dielectric constant

c) Dipolarity

d) High concentration in cells

e) High ionization potential

4. The following are organelles of prokaryotic cells:a) Plasma membrane

b) Mitochondria

c) Cytoplasm

d) Endoplasmic reticulum

e) Both A and C are correct

5. The endoplasmic reticulum is:a) Continuation of the plasma membrane

b) Site for protein synthesis

c) The major site for energy production

d) A double membrane organelle

e) Not found in hepatocytes

6. Mechanisms of transport across the plasma membrane:a) Are identical in prokaryotes and eukaryotes

b) Include pinocytosis

c) Include phagocytosis

d) Require glycolipids

e) Both B and C are correct

7. Water participates in the following reactions:a) Hydration

b) Dehydration

c) Hydrolysis

d) Thiolysise) All A, B and C are correct


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8. The bonds that are mostly involved in interactions of biomolecules include:a) The peptide bonds

b) The ionic bonds

c) The covalent bonds

d) Thioester bonds

e) Phosphodiester bonds

9. The dipolarity of water:a) Results in covalent interaction

b) Facilitates the solubility of most biomoleculesc) Disappears in the solid state

d) Is the basis for ionic interactions

e) Is none of the above

10. Buffers in the human body do not include:a) Proteins

b) Amino acids

c) Sulphuric acid & sulphated) Phospheric acid & phosphate

e) Carbonic acid & bicarbonate

11. Metabolic acidosis can result from:a) Excessive vomiting

b) Uncontrolled diabetes mellitus

c) Increased pHd) Increased carbohydrate intake

e) None of the above

12. The plasma pH is maintained by the buffering effect of:a) Proteins

b) Carbonic acid & Bicarbonate

c) The kidney

d) Gastric HCl

A, B and C are correcte)

13. Buffers in the human body do not include:a) Carbonic acid bicarbonate

b) Plasma proteins

c) Sulphuric acid & sulphated) Phospheric acid & phosphate

e) Hemoglobin

14. The mitochondrion:a) Has a higher density than the nucleus

b) Sediment before the nucleus in gradient centrifugation

c) Is a site for protein synthesis

d) Has the same size as the nucleus

e) Is absent in eukaryotes


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15. The equation pH=pK + Log (Conjugate acid/ Conjgate base):a) Is known as the Handerson Hasselbalch equation

b) Assumes that water ionizes

c) Assumes that water does not ionize

d) Applies to strong acids

e) is incorrect

16. At neutral pH, a mixture of amino acids in solution would be predominantly:a) Dipolar ions

b) Nonpolar molecules

c) Positive and monovalent

d) Hydrophobic

e) Negative and monovalent

17. The cytosol:a) Is composed of all subcellular organelles except the nucleus

b) Sediments before the nucleus in gradient centrifugation

c) Is the site for glycogen synthesisd) Contains enzymes of the TCA cycle

e) Is absent in prokaryotes

18. Interactions between biomolecules usually involve:a) Covalent bonds and hydrogen bonds

b) Ionic bonds and hydrogen bonds

c) Disulphide bridges and hydrophobic interactions

d) Hydrogen bonds and disulphide bridges

e) All of the above

19. Bonds involved in the interactions between biomolecules usually include:a) Covalent bonds

b) Hydrogen bonds

c) Ionic bonds

d) Hydrophobic interactions

e) B, C and D are all correct

20. Which of the following bonds is covalent?a) Hydrophobic

b) Hydrogen

c) Disulphided) Electrostatic

e) Ionic

21. Metabolic acidosis:a) Results from high bicarbonate in the blood

b) Is associated with increase in pH

c) Occurs in uncontrolled diabetes mellitus

d) Results from excessive vomiting

e) None of above is correct


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22. Reactions which involve water include:a) Thiolysis

b) Phosphorylysis

c) Hydrolysis

d) Hydrogenation

e) Dehydrogenation

23. Water:a) Has high melting point

b) Has low dielectric constant

c) Does not contribute in interaction of biomolecules

d) Has high concentration in cells

e) Ionizes completely at 25oC

24. The intestinal bicarbonate is produced by:a) Stomach

b) Duodenum

c) Jejunumd) Pancreas

e) Colon

25. pH of a buffer solution can be determined by:a) -log [base]/[acid]

b) -log [acid]/[base]

c) -log [acid-base]

d) pK + log [base]/[acid]

e) pK + log [acid]/[base]

26. Peroxisome site for synthesis of:a) Ether glycerophospholipids

b) Dolicols

c) Cholesterol

d) Triacylglycerol

e) A, B and C are correct

27. The physiological buffers that maintain intracellular pH include:a) Proteins

b) Bicarbonate

c) Phosphate

d) A, B and C are correcte) Albumin

28. The plasma pH that is most suitable with human life is:a) 6.8 - 8.7

b) 7.0 - 8.5

c) 6.0 - 8.5

d) 7.35 7.45

e) 7.45 7.95

29. The plasma membrane of the cell:a) Contains proteins

b) Is a lipid bilayer


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c) Is selectively permeable

d) Is different from the mitochondrial membrane

e) Is all of the above

30. The pH is:a) The hydrogen ion concentration in solution

b) Measured by colorimeter

c) The same in all body fluid compartments

d) Maintained by buffers

e) Dependent on ionization of strong acids

31. The following are found in prokaryotic and eukaryotic cells:a) Plasma membrane and cytosol

b) Nucleus and plasma membrane

c) Cytosol and endoplasmic reticulum

d) Mitochondria and cytoskeleton

e) Ribosomes and mitochondria

32. In cell fractionation:a) Mechanical shearing and detergent solubilization can be used

b) Gradient centrifugation separates organelles in one step

c) Nuclei sediment in the first pellet in differential centrifugation

d) Subcellular organelles can be identified by molecular markers

e) All of the above are correct

33. A patient has aciduria with a urine sample at pH 4.9. What is the approximate ratioof lactic acid molecules to lactate ions?

a) 1 : 100

b) 100 : 1

c) 10 : 1d) 1 : 10

e) 1 : 1

34. What is the pH of a buffer solution (HA and A) where HA is 100x the concentrationof A? (pK of HA is 6.8):

a) 4.8

b) 6.8

c) 5.8

d) 7.8

e) 8.8

35. Buffer capacity is:a) Greatest at a pH equal to the pKa of the acid form of a buffer pair in a

closed system

b) The change in pH that results from adding a given amount of acid or base to

a solution

c) Both A and B

d) Neither A nor B

e) Dependent on the concentration of the buffer

36. Plasma (HCO3-) is regulated by:a) The rate of respiration

b) Acidification of urine by the kidney


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c) The rate of urea synthesis in the liver

d) Pancreatic production of HCO3-

e) Loss of bicarbonate in vomiting and diarrhea

37. The cellulose is:a) An important constituent of the human muscles

b) Important in human diet

c) The main constituent of the plant cell wall

d) Made up of glucose units attached by alpha- 1,4 glycosidic linkage

e) Degraded to free glucose in humans

IQUESBIOCHEMICAL TECHN

1. In gel filteration, biomolecules are separated according to:a) The net charge

b) The difference in molecular weightc) Ability of diffusion through porous membranes

d) Polarity

e) Solubility

2. Radio Immune Assay (RIA):a) Is used for purification of hormones

b) Involves the use of radioactive elements

c) Is used for quantitative measurements of hormones

d) Requires a pure antigen of known concentration

e) "A" is the only wrong statement

3. Electrophoresis:a) Involves the use of polyacrylamide gel

b) Can be used for purification of proteins and nucleic acids

c) Is usually followed by Western blotting for proteins

d) A, B and C are all correct

e) Only B is correct

4. The following technique is the most suitable for the separation of a mixture of the 20amino acids:

a) Two dimensional electrophoresis

b) Gel filteration

c) Affinity chromatography

d) Dialysis

e) RIA

5. Chromatography:a) Is a technique for protein sequencing

b) Is a separation technique

c) Involves a mobile phase and stationary phase

d) Is exemplified by gel filteration

e) Only B,C and D are correct

6. Dialysis:a) Involves separation of molecules according to density


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b) Is based on diffusion across a porous membrane

c) Is a type of chromatography

d) Can be used to separate 2 molecules with the same molecular weight

e) The molecular weight is not important in the technique

7. Ion exchange chromatography:a) Used for sequencing of proteins

b) Useful in separation of proteins

c) Affinity chromatography

d) Dialysis

e) RIA

8. Electrophoresis:

a) Is based on centrifugal forceb) Cannot be used for separation of proteins and DNA

c) Requires electrical power source

d) Is based on passive diffusion of biomolecules

e) Is a technique for mammalian cell culture

9. A mixture of amino acids can be separated by:a) ELISA

b) RIA

c) Electrophoresis

d) Dialysis


10. In electrophoresis, the rate of migration depends on:a) Net electrical charge of the molecule

b) Size and shape of the molecule

c) Temperature of operation

d) Both A and B are correct


11. Chromatography technique can be used to seperate:a) Proteins

b) Amino acidsc) Lipids

d) Both A and B are correct


12. The following method is used only to detect RNA and can be used to measure thedifference in levels of specific mRNA in different tissues:

a) Northern blot analysis

b) Polymerase chain reaction

c) Restriction fragment length polymorphism linkage analysis

d) DNA fingerprint analysis

e) Southern blot analysis


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13. Radio Immune Assay:a) Is based on centrifugal force

b) Is used for quantitative measurement of abundant biomolecules

c) Requires antibodies and radioisotopes

d) Is used for measurement of plasma albumin

e) Has low sensitivity and high specifity

14. Dialysis:a) Is an ideal separation technique

b) Involves movement of molecules through a porous membrane

c) Depends on the difference in size and concentration

d) Is useful after affinity chromatography

e) B, C and D are correct

15. ELISA:a) Is a separation technique

b) Involves use of radioisotopes

c) Is ideal for quantitative measurements of hormonesd) Involves change of color in enzymatic reactions

e) Is not specific

16. The following is correct:a) Western blotting is for proteins

b) Northern blotting is for RNA

c) Southern blotting is for DNA

d) Transfer follows separation by electrophoresis

e) All of the above is correct

17. The following statements are true regarding Southern blotting except:a) It is the transfer of DNA from a gel onto a nylon membrane

b) It involves transfer of double stranded DNA from a gel to nylon membrane

c) It is helpful in detection of certain stains of infectious agents

d) Is useful for detection of a mutation in a given gene

e) It uses capillary diffusion for fragment transfer

18. RFLP stands for:a) Restriction fragment length position

b) Restriction fragment length polyploidy

c) Restriction fragment length phenotype

d) Restriction fragment length polymorphisme) Restitution fragment loose polymorphism

19. The following statements are true regarding agarose electrophoresis except:a) DNA migrates towards the negative electrodes

b) Large molecules migrate more slowly than small molecules

c) Ethidium bromide is used to visualize the DNA

d) Bromophenol blue is indicative of the distance migrated by DNA

e) Ultra-violet light is needed

20. The following techniques are used to immobilize the corresponding biomolecules:

a) Southern blotting for proteinsb) Northern blotting for RNA

c) Southern blotting for DNA


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d) Northern blotting for DNA


ENZYMES

1. Oxidoreductases include:a) Catalases and Mutases

b) Oxygenases and Dehydrogenases

c) Dehydrogenases and Ligases

d) Aminotransferases and Racemases

e) Epimerases and Oxidases

2. Michaelis constant of enzyme (Km) is:a) The substrate concentration which gives maximal velocity

b) The substrate concentration which gives 1/2 the maximal velocity

c) 1/2 the substrate concentration which gives maximal velocity

d) The enzyme concentration which gives maximal velocity

e) The enzyme concentration which gives 1/2 the maximal velocity

3. A competitive inhibitor:a) Increases the Km of the enzyme

b) Decreases the Vmax of the enzyme

c) Increases the Vmax of the enzyme

d) Decreases the Km of the enzymee) Increases both Km and Vmax of the enzyme

4. The non-protein part of an enzyme is called:a) Apoenzyme

b) Holoenzyme

c) Allosteric Enzyme

d) Isoenzyme

e) Coenzyme

5. The major 6 classes of enzymes include:a) Transferases and Oxygenases

b) Isomerases and Lyases

c) Hydrolases and Epimerases

d) Oxidoreductases and Catalases

e) Transaminases and Transferases

6. Enzymes:a) Increase the energy barrier for a reaction

b) Are recovered chemically altered after a complete reaction

c) Increase the equilibrium constant of the reaction

d) Activity is subject to regulatione) Are exclusively proteins


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7. Coenzymesa) The non-protein part of enzymes

b) Needed for enzyme activity

c) Usually vitamin derivatives

d) Termed prosthetic group if bonded tight to their enzymes

All of the above are correcte)

8. At Vmax of an enzyme catalyzed reaction:

a) Further increase in substrate concentration increases the rate of the reaction

b) All the enzyme molecules are combined with substrate

c) The substrate concentration that produces maximal velocity is termed Km

d) Half the enzymes are combined with substrate

e) Km is maximum

9. In case of non-competitive inhibition of enzymesa) Vmax can not be reachedb) There is no significant alteration of the active site

c) Inhibitor is structurally similar to the substrate

d) Inhibitor can be removed by increasing substrate concentration

e) Vmax is increased

10. Isoenzymes:a) Are factors required for enzyme activity

b) Are functional plasma enzymes

c) Show similar responses to inhibitor molecules

d) Are important tools in the diagnosis & prognosis of diseasee) Catalyze oxidation-reduction reactions

11. Hydrolases enzymes include:a) Racemases and oxygenases

b) Isomerases and lyases

c) Peptidases and lipases

d) Oxidoreductases and catalases

e) Transaminases and hydralases

12. Which of the following statements is true of enzyme catalysts?

a) To be effective they must be present at the same concentration as theirsubstrate

b) They can increase the equilibrium constant for a given

reaction by a thousand-fold or more

c) They lower the activation energy for conversion of substrate to product

d) Their catalytic activity is independent of pH

e) They are generally equally active on D and L isomers of a given substrate

13. Allosteric effector influences the enzyme activity by:a) Covalently modifying the enzyme

b) Binding to the substrate and altering its conformation

c) Competing for catalytic site with substrated) Changing the specificity of the enzyme for its substrate

e) Binding to a site on the enzyme distinct from catalytic site


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14. The following enzyme complex requires both thiamine and lipoic acid:a) Malate dehydrogenase

b) Alpha-ketoglutarate dehydrogenase

c) Fumarase

d) Isocitrate dehydrogenase

e) Succinate dehydrogenase

15. Sterioisomers:a) Diversify physical and chemical properties of molecules

b) Have the same spatial configuration

c) Exhibit enzyme specifity

d) Include epimers, anomers and enantiomers

e) All A, C and D are correct

16. In an enzyme catalyzed reaction:a) Enzymes increase the energy barrier for the reaction

b) Enzymes form a perminant complex with the substrate

c) After the reaction, enzymes are recovered unchanged

d) V-max is reached in the presence of a non-competitive inhibitore) The equilibrium constant is decreased

17. Isomerases:a) Racemases and mutases

b) Phosphatases and hydratases

c) Lyases and oxidases

d) Transaminases and kinases

e) Hydratases and glucosidases

18. Subclasses of oxidoreductases include:

a) Kinases and oxygenasesb) Reductases and dehydrogenases

c) Racemases and oxidases

d) Catalases and aminotransferases

e) Peroxidases and anomerase

19. The active site of an enzyme:a) Is rich with hydrophobic amino acid side chains

b) Binds allosteric effectors

c) Is similar in shape to the substrate

d) Occupies most of the enzyme molecule


20. Coenzymes:a) Are small organic molecules needed for enzyme activity

b) Are associated with apoproteins

c) Are vitamin derivatives

d) Are called prosthetic groups if they are tightly bound to the enzyme


21. In competitive inhibition of an enzyme:a) Km and Vmax are decreased

b) Inhibitor is structurally similar to the substratec) Inhibition cannot be reversed by increasing substrate concentration

d) Vmax is decreased


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e) The inhibitor binds to the regulatory site on the enzyme

22. In non-competitive inhibition of enzyme activity:a) Both Vmax and Km are increased

b) Inhibitor has no structural resemblance to the substrate

c) There is a significant alteration of the active site

d) Vmax is decreased

e) A is the only wrong answer

23. The following statements describe Allosteric enzymes:a) Effectors may enhance or inhibit substrate binding

b) Binding of the substrate to the Allosteric site displaces the effectors

c) They are always multimeric proteins

d) The regulatory site is identical to the active site

e) Binding of substrate to the active site releases allosteric effector

24. The following statements about regulation of enzyme activity are correct:

a) Phosphorylation/ dephosphorylation is the common covalent modificationb) Regulatory enzymes usually catalyze reversible reactions

c) Allosteric inhibitors are usually the end products

d) Increase in the enzyme level has no effect

e) Irreversible inhibition is physiological type of regulation

25. Phosphorylation/ dephosphorylation of enzymes:a) Occurs on specific serine and threonine residues

b) Is a covalent type of modification

c) Is a reversible type of regulation

d) Is achieved by the activities of protein kinases and phosphatases


26. The enzyme for starch digestion is:a) Salivary amylase

b) Pancreatic amylase

c) Lysosomal glucosidase

d) Both A and B


27. Hydrolases include:a) Catalases and mutases

b) Oxygenases and dehydrogenasesc) Esterases and glucosidases

d) Aminotransferases and racemases

e) Epimerases and oxidases

28. The following enzymes are absent in muscles but are present in the liver:a) Pyruvate carboxylase and citrate synthase

b) Glucose-6-phosphatase and glycerol kinase

c) Lactate dehydrogenase and isocitrate dehydrogenase

d) Pyruvate dehydrogenase and beta-ketothiolase

e) Glycogen synthase and 3-HMG CoA synthase

29. Which of the following statements is true of enzyme catalysts?


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a) To be effective, they must be present at the same concentration as their

substrate

b) They can increase the equilibrium constant for a given reaction by a

thousand-fold or more

c) They lower the activation energy for conversion of substrate to product

d) Their catalytic activity is independent of pH

e) They are generally equally active on D and L isomers of a given substrate

30. Isoenzymes:a) Are differentiated by dialysis

b) Show the same electrophoretic mobility

c) Include lactate dehydrogenase

d) Are used as diagnostic tools

e) Both C and D are correct

31. The pancreatic enzyme not involved in protein digestion is:a) Carboxypeptidase

b) Trypsin

c) Lipased) Elastase

e) Chymotrypsin

32. Restriction enzymes:a) Recognize specific nucleotide sequences in DNA

b) Cut both strands of DNA

c) Often produce single stranded tails

d) Do all of the above

e) Do none of the above

33. Enzymes involved in hydrolysis:a) Are called decarboxylases

b) Use folic acid as a coenzyme

c) Include dehydrogenases

d) Include peptidases

e) Always require coenzyme

34. Enzymes and pH:a) All enzymes have one optimum pH

b) Enzymes in the stomach require alkaline pH

c) All enzymes in eukaryotic cells require the same pH

d) The optimum pH is the one at which the enzyme has maximum activitye) The pH is the same in the lysosome and plasma

35. Isomerases:a) Catalyze oxidation-reduction reactions

b) Do not change the structural formula of the substrate

c) Include transaminases

d) Use water to break covalent bonds

e) Require ATP to form covalent bonds

36. The following vitamin work as coenzymes with the corresponding enzyme:a) Biotin and carboxylases

b) Cobalamin with isomerasesc) Retinol with lyases

d) Riboflavin with hydrolases


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e) Thiamin and isomerases

VITAMINS

1. Vitamin A:

a) Deficiency can give rise to xerophthalmiab) Is normally excreted in urine

c) Carnitine, Retinine and Retinone are known forms

d) Is required for collagen synthesis

e) Can be synthesized by intestinal flora

2. Vitamin D:a) Requires parathyroid hormones for activation

b) Is water-soluble

c) Lowers calcium level in the blood

d) Deficiency from overexposure to the sun

e) Is not required in the diet

3. Vitamin K:a) Is derived from cholesterol

b) Is synthesized by intestinal florac) Deficiency causes night blindness

d) Cannot be stored in the bodye) Is involved in transamination reactions

4. Beriberi:

a) Is due to deficiency of pyruvate dehydrogenase complexAffects the nervous system and the heartb)

c) Is due to deficiency in Vitamin C

d) Is associated with bone deformity

e) Can be treated by iron supplements

5. Vitamin B12:a) Is a potent anti-oxidant

b) Deficiency causes pellagra

c) Vegetable seeds are a major source

d) Is not stored in the body

Requires the intrinsic factor for absorptione)

6. Pyridoxal Phosphate:a) Is vitamin B5b) Deficiency causes rickets

c) Is coenzyme with pyruvate carboxylase

d) Can be synthesized in the human body

Is needed by the enzyme alanine transaminasee)

7. The following is formed in the liver:a) Cholicalciferol

b) 7- dehydrocholesterolc) 1, 25- dihydroxycholecalciferol

hydroxycholecalciferol-25d)


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e) 24, 25- dihydroxycalciferol

8. Pernicous anemia is caused by:a) A deficiency of dietery vitamin B12b) A deficiency of dietery folic acid

c) Excessive production of HCl by parietal cells of the stomach

A deficiency of the intrinsic factord)

e) A deficiency of vitamin C

9. Vitamin A:a) Is important for growth and reproduction

b) Is obtained from beta-carotene

c) Retinol and retinoic acid are known forms

d) Is required for keratin synthesis

All of the above is correcte)

10. Pellagra:a) Due to deficiency of pyruvate dehydrogenase complex

Due to deficiency of riboflavinb)

c) Associated diarrhea, dermatitis and dementiad) Treated by supplementation of tyrosine

e) Inherited as autosomal recessive character

11. Thiamin pyrophosphate is essential coenzyme for:a) Pyruvate dehydrogenase and transketolase

b) Transketolase and lactate dehydrogenase

c) Glycogen phosphorylase and glucose-6-phosphatase

d) Lactate dehydrogenase and alpha-ketoglutarate dehydrogenase

None of the abovee)

12. Ascorbic acid:a) Deficiency causes hypochromic microcytic anemia

b) Is required for synthesis of epinephrine and collagen

c) Is required for synthesis of bile acids

d) Promotes iron absorption in GIT

All of the above are correcte)

13. The following is not true about cobalamin:a) Active form is methylcobalamin

b) Absorption requires a glycoprotein factor

c) Is required for metabolism of propionate

Deficiency results in hemolytic anemiad)e) Is involved in folate metabolism

14. The effects of vitamin A include all of the following except:a) Prevention of infection

b) Serving as an antioxidant

c) Cell differentiation

d) The visual cycle

e) Induction of certain cancers

15. The vitamin component of coenzyme A is:a) Riboflavin

b) Biotin


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c) Panthothenic acid

d) Nicotinic acid

e) Pyridoxine

16. Vitamin A:a) Deficiency can give rise to rickets

b) Is normally excreted in urine

c) Carnitine, Retinine and Retinone are known forms

d) Is required for collagen synthesis

e) Is important for epithelial growth

17. Vitamin D:a) Requires thyroid hormones for activation

b) Active form is called calcitrol

c) Lowers calcium level in the blood

d) Deficiency from overexposure to the sun

e) Is not required in the diet

18. Vitamin K:a) Is derived from cholesterolb) Is needed for activation of prothrombin

c) Deficiency causes night blindness

d) Cannot be stored in the body

e) Is involved in transamination reactions

19. Beriberi:a) Is due to deficiency of pyruvate dehydrogenase complex

b) Is due to deficiency in Vitamin C

c) Is associated with bone deformity

d) Can be treated by iron supplementse) Is associated with high lactate in the blood

20. Vitamin B12:a) Is a potent anti-oxidant

b) Deficiency causes pellagra

c) Vegetable seeds are a major source

d) Binds transcobalamin I in the liver

e) Is absorbed in the stomach

21. Pyridoxal phosphate:

a) Is vitamin B2b) Deficiency is very common

c) Is coenzyme with pyruvate carboxylase

d) Can be synthesized in the human body

e) Is coenzyme with aminotransferases

22. Synthesis of vitamin B12 occurs in the:a) Stomach

b) Duodenum

c) Jejunum

d) Ileume) Colon


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23. The vitamins involved in energy producing reactions include:a) Folic acid, thiamin and niacin

b) Biotin, niacin and cobalamin

c) Thiamin, niacin and pantothenic acid

d) Cobalamin, ascorbic acid and riboflavin

e) Pyridoxine, folic acid and cobalamin

24. The following vitamins act as coenzymes with dehydrogenases:a) Thiamin and panthothenic acid

b) Biotin and pyridoxine

c) Cobalamin and folic acid

d) Ascorbic acid and biotin

e) Niacin and riboflavin

25. The following vitamins are involved in hemopoiesis:a) Ascorbic acid and thiamin

b) Folic acid and cobalamin

c) Riboflavin and biotin

d) Pyridoxine and thiamine) Niacin and panthothenic acid

26. The vitamins synthesized by intestinal bacteria include:a) Thiamin and riboflavin

b) Biotin and vitamin K

c) Folic acid and cobalamin

d) Niacin and vitamin C

e) Vitamin D and panthothenic acid

CARBOHYDRATES

1. The following is the main aldohexose in the blood:a) Fructose

b) Mannose

c) Glucosed) Galactose

e) Alcose

2. Glycogen is:a) A storage form of carbohydrate in plants

b) A polymer of glucose and fructose

c) A structural polysaccharide

d) Abundant in adipose tissue

e) A branched sugar

3. The following properties are common for both glucose and ribose:a) Both are aldoses

b) Both are found in DNA and RNA

c) Both are found in disaccharidesd) Both are obtained on hydrolysis of amylopectin

e) Both are ketoses


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4. The following is a disaccharide and non-reducing sugar:a) Lactose

b) Fructose

c) Maltose

d) Sucrose

e) Cellubiose

5. Proteoglycans:a) Are composed of cellulose and pectin

b) Are the major source of energy for ruminants

c) Act as lubricants in the joints

d) Give a blue color with iodine

e) Are degraded to free glucose in the lumen of the intestine

6. Carbohydrates:a) Are polyhydroxyaldehydes or ketones

b) Are polyhydroxyphenols

c) Include glucagond) Are components of phosphingolipids

e) Circulate in the blood as polymers

7. Glycogen is:a) A storage form of carbohydrate in plants

b) A branched sugarc) A polymer of glucose

d) A structural polysaccharide


8. Benedict's test:a) Does not differentiate between reducing substances

b) Is not specific for glucose

c) Is positive for ascorbic acid

d) Involves an oxidation-reduction reaction


9. The following is a structural polymer of glucose:a) Amylopectin

b) Inulin

c) Amylose

d) Cellulose

e) Mannitol

10. The following properties are common for both D- glucose and D- ribose:a) Both are reducing sugars

b) Form intramolecular hemiacetal bondsc) Both are aldoses

d) A, B and C are correcte) A is the only correct answer


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c) Sucrose

d) Cellulose

e) Both A and B are correct

19. Inulin:a) Is a glycoprotein

b) Is the chief constituent of the framework of plants

c) Is a fructosan

d) Solution gives the blue colour with iodine

e) Is used only for determination of the glomerular filtration rate

20. The following are aldohexoses:a) Fructose and galactose

b) Mannose and fructose

c) Glucose and galactose

d) Galactose and ribose

e) Maltose and glucose

21. Glycogen is:a) A storage form of carbohydrates in plants

b) Main branched polymer of glucosec) A structural homopolysaccharide

d) Abundant in adipose tissue

e) Stored in the liver

22. Benedict's test:a) Is positive for ascorbic acid

b) Involves an oxidation-reduction reaction

c) Does not differentiate between reducing substancesd) Is specific for glucose


23. The following are polymers of glucose:a) Pectin and collagen

b) Inulin and glycogen

c) Amylose and cellulose

d) Cellulose and chitine) Mannitol and starch

24. The following properties are common for both D-glucose and D-ribose:a) Are reducing sugars

b) Form intramolecular hemiacetal bonds

c) Have functional groups that can form glycosidic linkages

d) Are aldoses


25. The following is a non-reducing sugar from plantsa) Glucose

b) Fructose

c) Maltose

d) Sucrosee) Trehalose


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d) Cellulose and fructose

e) Fatty acid sucrose

5. Glucose-6-phosphate deficiency:a) Is known as Von Gierke's disease

b) Is associated with hypoglycemia in the fed state

c) Inhibits the last step of glycogenolysis and gluconeogenesis in the liver

d) Is associated with hyperuricemia

e) B is the only wrong statement

6. In glycogenesis:a) ATP is required

b) Phosphoglucomutase catalyses irreversible step

c) Glucose residues are added to the reducing end of glycogen

d) Glycogen synthase is the key enzyme

e) 2 ATP molecules are consumed

7. In galactosemia:

a) Treatment involves restriction of glucose in dietb) The liver function can be seriously affectedc) Galactose is deposited in tissues

d) Galactose is readily converted to glucose

e) Galactosuria is the most serious manifestation

8. Uncoupling of oxidative phosphorylation:a) Decreases the oxygen consumption

b) Releases heat onlyc) Occurs during hypoxia

d) Causes a buildup of NADH

e) Produces more ATP

9. The enzyme not involved in glycolyisis is:a) Aldolase

b) Endolase

c) Pyruvate kinase

d) Phosphoglycerate mutase

e) Alpha phosphoglycerate dehydrogenase

10. Which of the following is not a glycolytic intermediate?a) Glucose-6-phosphate

b) Fructose-6-phosphate

c) Dihydroxyacetone phosphate

d) Pyruvate

e) Glycerol-3-phosphate

11. Which site utilizes glucose as an energy source exclusively in all conditions:a) Brain

b) Muscle

c) Liver

d) Fat cell

e) Erythrocyte

12. The following agent interferes with oxidative phosphorylation:a) Cyanide inhibits NADH-dehydrogenase


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b) Carbon monoxide inhibits Coenzyme Q

c) Rotenone enhances electron transfer

d) Oligomyein inhibits electron transfer

e) Dintrophenol uncouples phosphorylation from electron transfer

13. The following compounds are part of the pyruvate dehydrogenase complex:a) Thiamin diphosphate

b) Lipoamide

c) CoA

d) NAD+

e) All of the above

14. UDP-G:a) Is derived from vitamin B1

b) Is a substrate for the enzyme glycogen phosphorylase

c) Is intermediate in glycerophospholipid synthesis

d) Is not required for normal galactose metabolism

e) Can be formed from UDP-Galactose

15. Glycogen phosphorylase:a) Is a mitochondrial enzyme

b) Is activated by dephosphorylation

c) Acts by the same mechanism as intestinal amylase

d) Produces uridine diphosphate from glycogen

e) Produces glucose-1-phosphate

16. Fructose 2,6 bisphosphate:a) Is a glycolytic intermediate

b) Activates phosphofructokinase 1

c) Is synthesized by phopshofuctokinase 1

d) Enhances fructose 1,6 bisphosphate

e) Level in the liver is increased by glucagon

17. Pyruvate carboxylase:a) Converts acetyl CoA to pyruvate

b) Requires carnitine

c) Converts pyruvate to oxaloacetated) Is activated by high fructose 1,6 bisphosphate

e) Requires pyridoxal phosphate

18. In glycogen storage diseases:a) Von Gierke's disease is type III

b) Hypoglycemia is the main feature of type V

c) Type II is associated with glucose 6 phosphatase deficiency

d) Type IV is called Andersen's disease

e) Hepatomegally is the main feature of all types

19. Which of the following statements about galactosemia is correct:a) Treatment involves restriction of glucose in the diet


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b) A deficiency of glucokinase is the major case

c) Is treated by elimination of galactose from the diet

d) Can be treated by restricting sucrose in the diet

e) Is inherited as autosomal dominant character

20. Glucose-6-phosphate dehydrogenase:a) Is the key enzyme in glycogenesis

b) Deficiency can cause hemolytic anemia

c) Catalyses conversion of G6P to fructose-6-phosphate

d) Is important in muscles during exercise

e) Is not found in RBC's

21. Synthesis of glucose from pyruvate by gluconeogenesis in the liver:a) Occurs exclusively in the cytosol

b) Is inhibited during prolonged fasting

c) Requires participation of biotind) Requires lactate as intermediate

e) Occurs exclusively in the mitochondrion

22. In the TCA cycle:a) Four NADH molecules are produced

b) Substrate-level phosphorylation occur by the action of sccinyl CoAthiokinase

c) The reactions can proceed in the absence of molecular oxygend) Fumarase reactions occur immediately after isocitrate dehydrogenases

reactions

e) Glutamate dehydrogenase is a key enzyme

23. In fructose metabolism:a) Deficiency of hexokinase results in fructosuria

b) Glucokinase is the major enzyme

c) Fructokinase phosphorylates fructose

d) Fructose 6 phosphate is produced by fructokinasee) Aldolase A is the key enzyme

24. Oxidation of glucose by red blood cells gives:a) Lactate + NADH+H

b) 36 ATP molecules per molecule of glucosec) Lactate and NAD+d) Carbon dioxide and water

e) 2 NADPH

25. The pentose phosphate pathway:a) Produces ATP

b) Is a mitochondrial pathway

c) Is important for reductive biosynthesisd) Is least active in the liver

e) Is inhibited by high glucose levels

26. The following agent interferes with oxidative phosphorylation:a) Carbon monoxide inhibits cytochrome reductase


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b) Cyanide inhibits NADH-dehydrogenase


d) Oligomyein inhibits electron transfer and phosphorylation

e) Dintrophenol enhances ATP synthesis

27. UDP-Glucose:a) Is indirectly involved in bilirubin conjugation

b) Is a substrate for the enzyme 4-epimerase in lactating mammary gland

c) Is intermediate in sphingolipid synthase

d) Is required for galactose metabolism

e) All of the above

28. Glycogen synthesis:a) Is a mitochondrial pathway

b) Is activated during the fasting state

c) Occurs in the liver and muscled) Produces uridine diphosphate from glycogen

e) All of the above

29. Pyruvate is:a) Converted to acetyl CoA by pyruvate carboxylase

b) Four-carbon compound

c) Converted to oxaloacetate by pyruvate dehydrogenase complex

d) Converted to alanine by transamination

e) Intermediate in the TCA cycle

30. In glycogen storage diseases:

a) Fatigability and muscle cramps are main features of Von Geirke's diseaseb) Hypoglycemia is the main feature of type V

c) Type II is associated with glucose 6 phosphatase deficiency

d) Type IV is called Andersen's diseasee) Hepatomegally is the main feature of all types

31. The following enzyme would be impaired in biotin deficiency:a) Fructose 1,6-bisphosphate

b) Pyruvate kinase

c) PEP carboxykinase

d) Pyruvate carboxylase

e) Malate dehydrogenase

32. The following statement about the pentose phosphate pathway is correct:a) Pentoses can be formed both oxidatively and non-oxidant

b) This pathway is important to fatty acid synthesis because it produces

equivalents

c) Fructose 6 phosphate can be used to make ribose-5-phosphate

d) Glyceraldehyde-3-phosphate can be used to make dinitrophenol


33. The following is caused by deficiency in aldolase B:

a) Hereditory fructose intolerenceb) Jaundice

c) Hypoglycemia


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d) Catarct

e) Ataxia

34. The rate of glycolysis in the liver is increased by:a) Insulin

b) ATP

c) Citrate

d) NADH

e) Glucose 6-phosphate

35. The preparative step of glycolysis involves the following:a) ATP synthesis at the substrate level

b) The incorporation of Pi into a triose phosphate

c) The reduction of NAD+ to NADHd) The formation of 1,3-bisphosphoglycerate

e) Formation of triose phosphates from a hexose diphosphorase

36. The following is present in the liver, but is absent in muscles:a) Pyruvate carboxylase

b) Glycogen synthase

c) Lactate dehydrogenase

d) Pyruvate dehydrogenase

e) Glucose-6-phosphatase

37. The following enzyme utilizes FAD as a coenzyme:a) Malate dehydrogenase

b) Aconitasec) Succinate dehydrogenased) Isocitrate dehydrogenase

e) Lactate dehydrogenase

38. A patient complaining of painful cramps in the legs during exercise and has easyfatigability, the most likely cause is:

a) Diabetes mellitus

b) Deficiency of glucose-5-phosphatase

c) Deficiency of the debranching enzyme or muscle phosphorylase

d) Defective glycogen synthesis

e) Over-storage of glycogen

39. Malonate inhibits succinate dehydrogenase because:a) Binds irreversibly to the active site

b) Covalently modifies the enzyme

c) Resembles succinate but cannot react

d) Displaces he FAD coenzyme

e) Chelates a metal ion required by the enzyme

40. In oxidative phosphorylation:a) An electrochemical potential is created across the inner mitochondrial

membraneb) ATP is synthesized from ADP and Pi

c) Protons are pumped into the interspace between the inner and outer


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mitochondrial membranes

d) The energy released from the electron flow is directly used for synthesis of

ATP

e) D is incorrect

41. Phosphofructokinase-1:a) Is activated by high level of ATP

b) Catalyzes the only irreversible reaction in glycolysis

c) Is activated by the high level of AMPd) Converts fructose 1-phosphate to fructose 1,6-bisphosphate

e) Is costimulated with fructose 1,6 bisphosphatase

42. In gluconeogenesis:a) Pyruvate is converted to acetyl CoA

b) Valine and Leucine are substrates

c) Energy consumption is highd) Insulin is needed to enhance the synthesis of glucose

e) Acetyl CoA is a substrate

43. Glycogen synthesis:a) Is typically the reverse of glycogenolysis

b) Is mitochondrial pathway

c) Is very active in adipose tissue

d) Requires uridine diphosphate-glucose as intermediate

e) Is activated by adrenaline

44. Galactosemia:a) Causes mental retardation

b) Can cause liver failure

c) Is caused by deficiency of galactose-1-phosphate uridyl transferased) Can be treated by restricting galactose from the diet


45. The following can be obtained from the TCA cycle intermediates:a) Fatty acids and glucose

b) Cholesterol and ketone bodies

c) Heme and glutamine

d) A, B and C are correcte) Only B is correct

46. The tissue which can metabolize normally glucose, fatty acids and ketone bodies forATP production is:

a) Liver

b) Skeletal musclec) Brain

d) Red blood cell

e) All of the above

47. All of the following compounds are part of the pyruvate dehydrogenase complexexcept:

a) Thiamine diphosphate

b) Lipoamidec) Biotind) FAD


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e) NAD+

48. Which of the following glycolytic intermediates is a close precursor to TAG:a) Glucose 6 phosphate

b) Fructose 6 phosphate

c) Dihydroxyacetone phosphate

d) Pyruvate

e) 3-phosphoglycerate

49. The carbon skeleton of glucose can participate in the synthesis of:a) Purine ring

b) Fatty acid

c) Glutamine

d) Pyrimidine ring


50. The following agent interferes with oxidative phosphorylation:a) Cyanide inhibits NADH-dehydrogenaseb) Carbon monoxide inhibits coenzyme Q


d) Oligomyein inhibits electron transfer

e) Dintrophenol uncouples phosphorylation from electron transfer

51. In oxidative phosphorylation:a) Ubiquinone transfers electrons from complex I to complex II

b) Dinitrophenol inhibits the flow of electrons

c) The electrons transported from one FADH2 to oxygen will produce 3 ATP's

d) Complex IV contains coppere) Complex III is called cytochrome oxidase

52. In galactosemia:a) Cataract results from accumulation of galactose in the lens

b) The liver function can be seriously affected as a result of phosphate

depletion

c) Galactose is deposited in tissues

d) Galactose is readily converted to glucose

e) Galactosuria is the most serious manifestation

53. The pyruvate dehydrogenase complex defect is mainly manifestd in the followingcondition:

a) Beriberi

b) Pellagra

c) Pernicious Anemia

d) Scurvy

e) Rickets

54. The committed step in glycolysis is catalyzed by:a) Hexokinase

b) Phosphofructokinase-1

c) Pyruvate kinased) Phosphoglycerate mutase

e) Glyceraldehyde 3 phosphate dehydrogenase


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55. The following agent interferes with oxidative phosphorylation:a) Cyanide inhibits NADH-dehydrogenase

b) Carbon monoxide inhibits Coenzyme Q


d) Cyanide inhibits cytochrome oxidase

e) Oligomycin inhibits electron transfer

56. The pyruvate dehydrogenase complex:a) Requires pyridoxal phosphate

b) Is inactive when thiamin is deficientc) Deficiency results in pernicious anemia

d) Catalyses a carboxylation reaction

e) Is a key enzyme in the red blood cell

57. Activation of phophofructokinase-1 in the liver:

a) Inhibits hexokinaseb) Enhances gluconeogenesis

c) Enhances the activity of pyruvate kinase

d) Occurs as a result of high glucagons/insulin ratio

e) Results in accumulation of fructose-6-phosphate

58. Which of the following cells utilize glucose, fatty acid and ketone bodies as fuels:a) Neuron

b) Myocytec) Hepatocyte

d) Adipocyte

e) Erythrocyte

59. Glycogen phosphorylase:a) Is activated by insulin

b) Is activated by dephosphorylation

c) Requires inorganic phosphate

d) Produces uridine diphosphate glucose from glycogen

e) Is a key enzyme in gluconeogenesis

60. In oxidative phosphorylation:a) Ubiquinone transfers electrons from complex I to complex II

b) Dinitrophenol inhibits the flow of electronsc) The electrons transported from one FADH2 to oxygen will produce 3 ATP

d) A decrease in oxygen supply increases the flow of the electrons through the

complexes

e) An increase in the rate of ATP synthesis will decrease electron transport

61. Glycogen:a) Is found in liver and muscle

b) Is a branched polysaccharide formed from glucose

c) Is responsible for maintenance of blood glucose level between meals

d) Excessively deposits in liver of von Geirk's disease patient


62. Fructose:


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d) 6-phophogluconate dehydrogenase

e) 3-HMG CoA synthase

70. Glycerol-3-Phosphate:a) Is produced by reduction of dihydroxyacetone phosphate

b) Is precursor of phosphatidic acid

c) Can be produced by glycerol kinase

d) Is intermediate in TAG synthesis


71. The following agent interferes with oxidative phosphorylation:a) Cyanide inhibits NADH dehydrogenase

b) Carbon monoxide inhibits coenzyme Q


d) Oligomycin inhibits complex Ie) Dinitrophenol uncouples phosphorylation from electron transfer

72. In the fed state:a) Glucose is converted to glycogen and stored in skeletal muscle

b) Adipose tissue converts triglycerides to glucose

c) Amino acids are transaminated to form ketone bodies

d) Glycogen stores in liver are depleted

e) Glycogen phosphorylase is in the active form

73. Twenty four hours after a meal, the primary source of glucose carbons for the brain

is:a) Skeletal muscle protein

b) Glycerol from adipose tissue

c) Dietary glucose

d) Muscle glycogen

e) Both A and B are correct

74. Activity of the following enzyme is expected to increase in the fed-state:a) Lactate dehydrogenase

b) Glucose 6-Phosphate dehydrogenase

c) Glucose 6-Phosphatase

d) Glycogen phosphorylasee) PEP carboxykinase

75. The following enzymes are absent in muscles but are present in the liver:a) Pyruvate carboxylase and citrate synthase

b) Glucose-6-phosphatase and glycerol kinase

c) Lactate dehydrogenase and isocitrate dehydrogenase

d) Pyruvate dehydrogenase and beta-ketothiolase

e) Glycogen synthase and 3HMG CoA synthase

76. Concerning inhibition of the electron transport chain:

a) Cyanide inhibits NADH dehydrogenaseb) Carbon monoxide inhibits coenzyme Q



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d) Oligomycin inhibits complex I

e) Dinitrophenol uncouples phosphorylation from electron transfer

77. Liver glycogen synthase and PFK-1:a) Are activated simultaneously in the fed state

b) PFK-1 is activated before glycogen synthase

c) Both are allosteric enzymes

d) Both are activated by insulin


78. Insulin activates PFK-1 in the liver by:a) Increasing the level of AMP

b) Phosphorylation

c) Increasing the level of fructose 2,6 bisphosphate

d) Inhibiting fructose 1,6 bisphosphatase


79. Metabolism of the major fuels mostly culminate in:a) Glucose 6 phosphate

b) Pyruvate

c) Oxaloacetate

d) Acetyl CoA

e) Fumerate

80. In the liver during the fed state:a) Glucokinase indirectly enhances uptake of glucose

b) Hexokinase is inhibitedc) Glucose 6 phosphate dehydrogenase is very active

d) Glycogen phosphorylase is dephosphorylated


81. Glycerol 3 phosphate dehydrogenase:a) Converts glycerol 3 phosphate to DHAP in the fed state

b) Converts DHAP to glycerol 3 phosphate in the fasting state

c) Catalyses a reversible reaction

d) Is an allosteric enzyme

e) Is a glycolytic enzyme

82. Liver enzymes which are active in the fed state include:a) Glycerol kinase

b) PEP carboxykinase

c) Pyruvate kinase

d) Glucose 6 phosphatase

e) Glycogen phosphorylase

83. Insulin:a) Activates acetyl CoA carboxylase

b) Causes the phosphorylation of acetyl CoA carboxylase

c) Stimulates lipolysisd) Inhibits the formation of malonyl CoA

e) Inhibits fatty acid synthesis in adipose cells


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84. Insulin exerts its effect on target tissue through:a) Enhancing tyrosine synthesis

b) Binding tyrosine kinase receptor

c) Increasing phosphorylation of all cellular proteins

d) Increasing intracellular cAMP

e) Inhibition of protein kinase C

85. Glucagon:a) Is a steroid hormone

b) Binds intracellular receptors

c) Mimic all actions of epinephrine

d) Enhances glycogenolysis in the liver

e) Is transcriptional enhancer

86. Hypoglycemia:a) Is caused by hyperinsulinemia

b) Is prominent feature of DKA

c) Enhances release of glucagon

d) Affects the brain seriously


88. In Diabetes Mellitus:a) Type II is more common than type one

b) Type I is more serious than type II

c) Type I is called insulin dependentd) DKA is usually associated with type I


89. Glucose alanine cycle:a) Serves to carry amino groups from the skeletal muscle to the liver

b) Requires participation of gluconeogenesis in the liver

c) Provides the working muscle with glucose made by the liver

d) Requires participation of transamination reactions in both the skeletal

muscle and the liver


90. Lactate is increased in the blood:a) During sleep

b) During exercise

c) In Von Gierke's disease

d) Thiamin deficiency

e) B, C and D are correct

91. Glucose, fatty acids and ketone bodies are normally oxidized for ATP production

by:a) Liver

b) Skeletal musclec) Brain

d) Red blood cell


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92. During prolonged starvation, all of the following tissues can use fuels other than

glucose except:a) Red blood cells

b) Muscle

c) Brain

d) Kidney

e) Adipose tissues

93. The enzyme which is not involved in glycolysis is:a) Aldolase

b) Enolase

c) Pyruvate kinase

d) Phosphoglycerate mutase

e) Alpha phosphoglycerate dehydrogenase

94. Activation of phosphofructokinase-1 in the liver:a) Inhibits hexokinaseb) Enhances gluconeogenesis

c) Enhances the activity of pyruvate kinase

d) Occurs as a result of high glucagons/insulin ratio

e) Results in accumulation of fructose 6 phosphate

95. Which of the following glycolytic intermediates is converted to a precursor of TAGsynthesis:

a) Glucose 6 phosphate

b) Fructose 6 phosphate

c) Dihydroxyacetone phosphated) Pyruvate

e) PEP

96. Human liver usually produces glucose during prolonged fasting from:a) Palmitic acid and alanine

b) Glycerol and lactatec) Leucine and Serine

d) Galactose and fructose

e) Lactate and acetyl CoA

97. The Electron Transport Chain:a) Produces ATP at substrate level

b) Produces 3 ATP's per FADH2c) Gets NADH and FADH2 from beta oxidation and TCA cycle

d) Occurs in the mitochondrial matrix

e) Is inhibited by carnitine

98. The Hexose Monophosphate Shunt:a) Is the same as PPP

b) Releases CO2c) Produces NADPH

d) Is active in the adrenal cortexe) All of the above is correct


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99. Phosphofructokinase-1:a) Allosteric enzyme

b) Activated by ATP

c) Catalyses a reversible step

d) Produces fructose 2,6 bisphosphate


100. Type 1 glycogen storage disease:a) Is known as Cori's disease

b) Is associated with cardiomegally

c) Causes hyperglycemia

d) Is known as McArdle's disease


101. In the TCA cycle:

a) Malate dehydrogenase catalyzes a reversible reactionb) Malonate is an intermediate

c) Two ATP molecules are produced

d) All reactions are reversible

e) All intermediates are phosphorylated

102. In gluconeogenesis:a) Lactate comes from the RBC's and the brain

b) Glycerol is produced from TAG in the adipose tissue

c) Linolenic acid is a substrate

d) The rate of glucose production increases during the fed state

e) B is the only correct answer

103. Glycogenolysis:a) Is synthesis of glucose from non carbohydrates

b) Produces fructose 1 phosphate

c) Is a cytosolic pathway

d) Is active in the fed state

e) Require glycogen synthase

104. In galactosemia:a) Galactosuria is the most serious maifestation

b) Cataract results from accumulation of galactose in the lensc) Galactose is converted to galactitol

d) The liver function can be seriously affected as a result of phosphate

depletion


105. Oxidative PPP:a) Needs F6P as Substrate

b) Is activated by high levels of NAP+

c) Catalyzes conversion of G6P to F6P

d) Is important in muscle during exercise

e) Is active in the fasting state

106. The TCA Cycle:


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a) Provides Acetyl CoA for Ketone Body Synthesis

b) Is inactive in the absence of Oxygen

c) Converts all amino acids to Glucose by Gluconeogenesis

d) Is blocked by excessive Beta-Oxidation

e) Can convert Oxaloacetate to Pyruvate

107. Glucose-6-Phosphatase Deficiency:a) Is known as Von Gierke's Disease

b) Is associated with Hypoglycemia

c) Inhibits Glycogenolysis & Gluconeogenesis in the liver

d) Is associated with Hyperuricemia


108. The following is required in both Glycogenesis and Glycogenolysis:a) CTP

b) Phosphoglucomutasec) Glucose residues are added to the reducing end of Glycogen

d) Glycogen Synthase

e) Insulin

109. The Liver:a) Has a high capacity for Fatty Acid Oxidation

b) Can produce Glucose from Glycerol

c) Is the only site for Ketogenesis

d) Activates acetoacetate to acetoacetyl CoA

e) D is the only wrong answer

110. In the fed state, glucose reaching the liver has the following fates:a) Is converted into Glycogen

b) May be converted into Triacylglycerols

c) Is oxidized to produce ATP

d) Is oxidized via PPP to generate ribose and NADPH


111. In the well-fed state:a) There is high glucose level in the portal blood

b) There is high chylomicrons in the portal blood

c) Hexokinase is very active in the liverd) Lipogenesis is active only in adipose tissue

e) The liver converts Lactate to Fatty Acids

112. The following liver enzymes have decreased concentration in the fasting state:a) G-6-Phosphatase

b) Phosphoenolpyruvate Carboxykinase

c) F1,6-Bisphosphate

d) G-6-P Dehydrogenase

e) Pyruvate Carboxylase

113. Metabolism of major fuels (glucose, fatty acids, amino acids) mostly culminate in:a) Glucose-6-Phosphate

b) Pyruvate


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c) Oxaloacetate

d) Acetyl CoA

e) Fumerate

114. In the fed state, glucose reaching the liver has the following fates:a) Is converted into Glycogen

b) May be converted into Triacylglycerols

c) Is oxidized to produce ATP

d) Is oxidized via PPP to generate ribose and NADPH


115. Glycogen synthesis:a) Is a reversible pathway

b) Is a mitochondrial pathway

c) Is activated during the fasting state

d) Occurs in the liver and muscle

e) Produces Uridine Diphosphate from Glycogen

116. Fructose 2,6 bisphosphate:a) Is not a glycolytic intermediate

b) Activates phosphofructokinase 1

c) Is synthesized by phopshofuctokinase 2

d) Inhibits fructose 1,6 bisphosphate


117. In glycogen storage diseases:a) Fatigability and muscle cramps are main features of Von Geirke's disease

b) Hypoglycemia is the main feature of type Vc) Type II is associated with glucose 6 phosphatase deficiency

d) Type IV is due to deficiency of the branching enzyme

e) Hepatomegally is the main feature of all types

118. The following enzyme requires biotin as a coenzyme:a) Fructose 1,6-bisphoshate

b) Pyruvate kinase

c) PEP carboxykinased) Pyruvate carboxylase

e) Malate dehydrogenase

119. All the following enzymes are present in the liver and muscle except:a) Pyruvate Carboxylase

b) Glycogen Synthase

c) Lactate Dehydrogenase

d) Pyruvate Dehydrogenase

e) Glucose-6-Phosphatase

120. The Pyruvate Dehydrogenase Complex:a) Requires pyridoxal phosphate

b) Deficiency results in pernicious anemia

c) Is inactive when Vitamin B1 is deficientd) Catalyzes a carboxylation reaction

e) Is a key enzyme in the Red Blood Cell


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LIPIDS

1. The following are essential amino acids:

a) Linoleic acid and Palmitic acidb) Palmitic acid and Archidonic acid

c) Linolenic acid and Linoleic acidd) Stearic acid and Linolenic acid

e) Linoleic acid and Arachidonic acid

2. Arachidonic Acid:a) Is a branched fatty acid

b) Contains 3 double bonds

c) Is a precursor for eicosanoidsd) Contains 5 double bonds

e) Is a 20-carbon saturated fatty acid

3. A membrane phospholipids that contains glycerol is:a) Phosphatidyl Choline

b) Sphingomyelin

c) Cerebroside

d) Ganglioside

e) Ceramide

4. Lipids are important in the human body because they act as:a) Enzymes

b) Immune molecules

c) Lubricants

d) Stored genetic information

e) Energy source

5. The following compound is a simple lipida) Methionine

b) Lecithin

c) Cholesterol

d) Triacylglycerol

e) Amylopectin

6. Fatty acids:a) Are always dicarboxylic


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b) Are only composed of an even number of C atoms

c) Are obtained from the hydrolysis of triacylglycerol

d) Contains glycerol

e) Are the only components of cell membrane lipids

7. The following are saturated fatty acids:a) Linoleic acid and archidic acid

b) Palmitic acid and stearic acid

c) Linolenic acid and myristic acid

d) Stearic acid and linolenic acid

e) Oleic acid and lauric acid

8. Arachidonic acid is:

a) The same as arachidic acidb) Essential fatty acid

c) The precursor of prostaglandins

d) Not found in membrane lipids

e) Is a 22-carbon compound

9. Membrane phospholipids which contain glycerol include:a) Lecithin and cardiolipin

b) Sphingomyelin and lecithin

c) Cerebroside and Phosphatidyl serine

d) Cardiolipin and gangliosides

e) Ceramide and phosphatidyl inosital

10. Lipids are important in the human body because they act as:a) Enzymes and hormones

b) Hormones and energy source

c) Coenzyme and enzymes

d) Stored genetic information

e) Energy source and lubricants

11. The following are derived lipids:a) Vitamin D and methionine

b) Lecithin and cholesterol

c) Cholesterol and palmitic acid

d) Dolicol and coenzyme Q

e) Amylopectin and prostaglandins

12. Structural lipids include:a) Gangliosides and aminoglycosides

b) Cerebrosides and cholesterolc) Phenylaline and phosphatidylserine

d) Phosphatidylserine and glucosamine

e) Glycosaminoglycans and proteoglycans

13. Lipids are stored in mammalian tissues:a) Starch


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b) Triacylglycerol

c) Cholesterol

d) Estrogen

e) Fatty acids

14. In mammals, cholesterol is:a) A normal membrane constituent

b) Converted to cholic acid by intestinal bacteria

c) Important source of energy

d) Parent molecule for sphingolipids

e) Synthesized in the liver mitochondria

15. In digestion and absorption of lipids:a) Bile pigments are important biological detergents

b) Hormone-sensitive lipase is secreted by the pancreas

c) Non-specific lipid esterase is the main digestive enzyme

d) Bile salts are important enhancers

e) TAG enters enterocytes directly

16. Unlike prostaglandins, thromboxanes:a) Are derived from arachidonic acid

b) Are synthesized cyclooxygenase pathway

c) Are released by platelets

d) Act as local hormones

e) Have 20 carbons

17. Complex lipids include:a) Gangliosides and peptidoglucans

b) Cerebrosides and cellulosec) Phenylalanine and phosphatidylcholine

d) Phosphatidylserine and cholesterol

e) Glycosaminoglycans and chitin

18. Triacylglycerol and Glycogen:a) Are storage form of energy in plants

b) Are polymers of glucose

c) Are storage form of energy in animals

d) Have the same energy yield on complete oxidation

e) Are mainly stored in the liver

19. A membrane phospholipids that does not contain glycerol is:a) Lecithin

b) Sphingomyelin

c) Cerebroside

d) Cardiolipin

e) Ceramide

20. Unsaturated fatty acids:a) Are obtained in the diet from animals

b) Are always in the cis configuration

c) Include linolenic acid and arachidonic acidd) Give important derivatives

e) Are water soluble


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21. Phosphatidylcholine:a) Is also known as lecithin

b) Is a major constituent of lung surfactant

c) Occurs in cell membranes

d) Can be obtained from phosphatidyl ethanolamine


22. Cholesterol is:a) Found in plants

b) Membrane lipid

c) Non-amphipathic lipid

d) Precursor of bilirubin

e) A source of energy

23. Cerebrosides:a) Include glucosylceramide

b) Are derived lipidsc) Contain sialic acid

d) Are glycerophospholipids

e) Are membrane glycoproteins

24. The following is an important function of cholesterol:a) Synthesis of acetylcholine

b) Synthesis of prostaglandins

c) Formation of bile salts

d) Formation of phosphatidylcholine

e) Increasing membrane rigidity

25. Sphingomyelins:a) Consist of phosphoric acid, choline and ceramide

b) Consist of ceramide, sphingosine and choline

c) Are glycosphingolipids

d) Are part of the skin pigment melanin

e) Are equally distributed in all tissues

26. The following is true about eicosanoids:a) Prostacyclines inhibit platelet aggregation

b) Thromboxanes cause platelet aggregation

c) Prostaglandins enhance smooth muscle contractiond) Leukotrienes are allergic mediators


27. The following are amphipathic membrane lipids:a) Triacylglycerol and cholesterylester

b) Cholesteryl esters and cerebrosides

c) Cholesterol and fatty acid

d) Glycerophospholipds and sphingomyelins

e) Galactosyl ceramide and glycerol

28. The following statement about simple lipids is true:a) TAG's always contain similar fatty acids


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11. Formation of ketone bodies:a) Occurs in the cytosol of the liver

b) Increases during fastingc) Starts from pyruvate

d) Requires lactate dehydrogenase

e) Is inhibited during fasting

12. Prostaglandins:a) Are neurotransmitters

b) Are derivatives of cholesterol

c) Are synthesized by cyclooxygenase from unsaturated fatty acidsd) Include propanol

e) Are found in adipose tissue

13. Concerning cholesterol biosynthesis:a) Two squalene units are required

b) The rate of synthesis is controlled by the rate of production HMG-CoA

c) The liver is the only site for synthesis

d) NADH is requirede) Mevalonate is an intermediate

14. For transport across the inner mitochondrial membrane, long chain fatty acids areattached to:

a) Coenzyme A

b) Acyl tansacylase

c) Phosphatidylethanolamine

d) Acyl transferase

e) Carnitine

15. The activity of lipoprotein lipase is stimulated by:a) Apo A

b) Apo B-48

c) Apo CIId) Apo E

e) Apo B-100

16. The rate-limiting step in the conversion of cholesterol to bile acids:a) Is side-chain oxidation

b) 12-alpha-hydroxylation

c) 7-alpha-hydroxylation

d) 7-beta-hydroxylatione) Conversion to coprostanol

17. Cholesterol is:a) A source of energy

b) A precursor of vitamin K

c) Not found in lipoproteins

d) Precursor of steroid hormones

e) The same as the steroid nucleus

18. Fatty acid oxidation is a significant source of energy in all of the following except:

a) Liverb) Skeletal muscle

c) Kidney


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b) Are synthesized from arachidic acid

c) Enhances smooth muscle contraction

d) Are involved in control of inflammation and blood pressure


27. Ketone bodies:a) Are synthesized in the mitochondria of the liver

b) Increase in the blood during starvation

c) Are good fuels for cardiac muscle

d) Increase in the blood in uncontrolled diabetes mellitus


28. During diabetic ketoacidosis there is a rise in:a) Plasma free fatty acidsb) Plasma insulin level

c) Blood pH

d) Plasma alkali reserve

e) Bicarbonate

29. Denovo synthesis of cholesterol occurs mainly in:a) Adipose tissue and muscles

b) Liver and intestine

c) Endothelial cells and hepatocytes

d) Pancreas and bone marrowe) All of the above

30. Lipoprotein lipase is:a) Activated by insulin

b) Active during the fed state

c) Hydrolyses TAG

d) Activated in presence of Apo CII


31. Examples of sphinglipodoses include:

a) Gaucher's disease and Tay-Sacch's diseaseb) Niemann-pick disease and von Gierke's disease

c) Andersen's disease and Krabbe's disease

d) Fabry's disease and rickets

e) Farber's disease and Refsum's disease

32. Acetyl CoA carboxylase:a) Is activated by citrate

b) Converts acetyl CoA to pyruvate

c) Converts acetyl CoA to malonyl CoA

d) Is a cytosolic enzyme


33. The following is correct:


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a) The liver uses ketone bodies and fatty acids as major fuels

b) Skeletal muscles use glucose, fatty acids and ketone bodies as fuels

c) Red blood cells oxidize acetylCoA to carbon dioxide

d) Heart muscles are totally dependent on glucose as fuel

e) The brain uses glucose and ketone bodies as normal fuels

34. Fatty acid synthesis:a) The committed step is catalyzed by fatty acid synthase

b) Steps shared between cytosol and mitochondria

c) Carnitine is needed for fatty acid transport to the mitochondriad) Pyruvate carboxylase is a key enzyme

e) The liver and muscles are major sites

35. Ketone bodies:a) Include acetoacetate and acetoacetyl CoA

b) Are produced in excess in the fed state

c) Are synthesized from pyruvate

d) Are produced by liver and kidneye) Are preferred fuels by cardiac muscles

36. The contents of HDL do not include:a) Apo A

b) Cholesterol

c) Apoprotein B-48d) Apo E

e) Apo C

37. Prostaglandins:

a) Are local hormonesb) Are derivatives of cholesterol

c) Are synthesized by lipooxygenase from unsaturated fatty acids

d) Include propanol

e) Are found in adipose tissue only

38. In cholesterol biosynthesis:a) Prostacyclin and squalene are intermediates

b) 3-HMG CoA is a precursorc) Rate is enhanced by epinephrine

d) Thiamin pyrophosphate is coenzyme with 3-HMG CoA reductase

e) All steps are reversible

39. Lipoprotein lipase:a) Is cystolic enzyme

b) Is the same as HSL

c) Is active during starvation

d) Requires biotin as coenzyme

e) Is activated by insulin

40. 3-HMG CoA is:a) Intermediate in cholesterol degradation

b) Intermediate in ketone body synthesisc) Precursor of fatty acids

d) Final product in ketogenesis


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e) Three carbon compound

41. Triacylglycerol and glycogen:a) Are storage form of energy in animals and plants

b) Are synthesized from glucose

c) Are transported between tissues as lipoprotein particles

d) Have the same energy yield on complete oxidation

e) Are mainly stored in the liver

42. The chylomicron:a) Carries cholesterol from the intestine

b) Contains mainly TAG

c) Has apoprotein B-48

d) Has lower density than HDL


43. Citric acid:

a) Is produced in the mitochondria as a member of the TCA cycleb) Is an allosteric activator of acetyl CoA carboxylase

c) Is a source of cytoplasmic acetyl CoA

d) Is cleaved in the cytosol by an ATP-dependent lyase

e) All of the above

44. Inherited disorders of B-oxidation:a) Include Refsum's disease which is due to absence of peroxisomes

b) Acyl CoA dehydrogenase deficiency causes hyperglycemia

c) Include dicarboxylic aciduria

d) Causes hemolytic anemia

e) Includes McArdle disease

45. Acetyl CoA Carboxylase:a) Catalyzes committed step in glycogen synthesis

b) Converts acetyl CoA to pyruvate

c) Converts acetyl CoA to malonyl CoA

d) Is a mitochondrial enzyme

e) Needs folate as co-enzyme

46. Malonyl CoA:a) Is activated form of acetyl CoA

b) Is increased during glucagons stimulationc) Inhibits carnitine palmitoyl transferase-1

d) Synthesis does not require biotin as cofactor

e) Can be converted to glucose in the liver

47. Lipolysis in adipose tissue:a) Is catalyzed by lipoprotein lipase

b) Is enhanced in the fed state

c) Produces fatty acid and glycerold) Is enhanced by insulin secretion

e) Produces ketone bodies

48. Ketone bodies:


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a) Formation occurs in the mitochondria of hepatocytes

b) Levels in blood increase with prolonged starvation

c) Are increased in blood patients with uncontrolled diabetes mellitus type-1

d) Are prefentially used by heart muscle


49. Prostaglandins:a) Primarily synthesized from eicosanoic acids

b) Closely related to thromboxanes

c) Potent smooth muscle contractor

d) Local hormone


50. In lipoproteins:a) VLDL is the major carrier of dietary triglycerides

b) LDL contains endogeneous cholesterolc) Chylomicrons are synthesized in the liver

d) Hormone-sensitive lipase is a component of HDL

e) The protein component increases the hydrophobicity

51. Gallstone blocking the common bile duct will result in the impaired intestinal

absorption of all the following except:a) Retinol

b) Cholecalciferol

c) Cholesterol

d) Diacylglycerol

e) Folic Acid

52. Beta-oxidation of a fatty acid:

a) Produces ATP at substrate levelb) Involves two steps of reduction of fatty acid

c) Has a preference for fatty acids shorter than 12 carbons

d) Requires NAD+e) Is a cystosolic pathway

53. Glycerol-3-phosphate in adipose tissue arises primarily from:a) Reduction of dihydroxyacetone phosphate

b) Hydrolysis of phosphatidic acid

c) Phosphorylation of glycerol by glycerol kinase

d) Selective uptake from blood

e) Reduction of glyceraldehydes-3-phosphate

54. Cholesterol is:a) A normal membrane constituent of plant cells

b) Converted to cholic acid by intestinal bacteria

c) Important source of energy

d) Parent molecule for cholecalciferole) Synthesized in the liver mitochondria

55. Derivatives of cholesterol include all of the following except:a) Cholecalciferol

b) Cortisolc) Retinold) Chenodeoxycholate


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e) Aldosterone

56. The activity of acetylCoA carboxylase is enhanced:a) Dephosphorylation

b) Insulin

c) Citrate

d) Esterification of fatty acylCoA


57. In lipogenesis and beta oxidation:a) Carnitine palmitoyl transferase I is enhanced by malonyl CoA

b) The two pathways are mitochondrial

c) High level of cytosolic fatty AcylCoA enhances lipogenesis

d) Insulin enhances malonyl CoA synthesis which indirectly inhibits beta

oxidation

e) NADPH is needed

58. Conversion of glucose to TAG in the liver requires all of the following except:

a) Acetyl CoA carboxylaseb) Fatty acid synthase

c) Pyruvate dehydrogenase

d) Glucose 6 phosphatase

e) Glycerol 3 phosphate dehydrogenase

59. All of the following are synthesized in the liver in the fed state except:a) VLDL

b) Glucosec) LDL

d) PRPP

e) Cholesterol

60. During fasting the following pathways are active in the liver except:a) Glycogenolysis

b) Glycolysis

c) Ketogenesis

d) Beta oxidation

e) Gluconeogenesis

61. Concerning cooperation between the liver and adipose tissue:a) TAG is synthesized in the adipose tissue and transported to the liver

b) Ketone bodies are synthesized by the liver and consumed in adipose tissuec) LDL is released from adipose tissue and oxidized in the liver

d) VLDL is synthesized in the liver and converted to HDL in adipose tissue

e) HDL is synthesized in the liver and degraded in adipose tissue

62. The main sources of energy in skeletal muscle during vigorous exercise are:a) Fatty acids and creatine phosphate

b) Anaerobic oxidation of glucose and creatine phosphate

c) Blood glucose and ketone bodies

d) Fatty acids and glycerol


63. In the cardiac muscle:a) Glycogen is the main energy reserve


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b) Ketone bodies are preferred over glucose for energy production

c) Anaerobic glycolysis is vital

d) Fatty acids are not used in the fed state

e) None of the above is correct

64. In the brain:a) Most of the energy is used for generation of nerve impulses

b) Glucose is a sole fuel under normal conditions

c) There is a high turnover of biomolecules

d) Ketone bodies can be utilized


65. Insulin promotes fat storage in adipose tissue cells by:a) Inhibition of HSL

b) Stimulation of lipoprotein lipase

c) Stimulation of glycolysis

d) Enhancing glucose uptake


66. Ketone bodies are present in high levels in the blood when:a) Hepatic glycogen levels are high

b) Fat is being actively synthesized

c) Protein synthesis in muscle is elevated

d) Blood glucose is high

e) Fatty acid oxidation is high in the liver

67. Malonyl-CoA:a) Is produced from citrate

b) Is increased during glucagons stimulation

c) Inhibits carnitine palmitoyl transferase-1d) Synthesis require folate as a coenzyme

e) Is converted to glucose in the liver

68. The following is correct about chylomicron:a) It is formed in the intestinal mucosal cells

b) It contains the apoprotein B48

c) It is carried from the intestinal mucosa to the circulation through lymphatic

vessels

d) The major load is dietary triacylglycerol


69. The major carrier of cholesterol from the liver to the tissues is:a) HDL

b) IDL

c) LDL

d) VLDL

e) HDL2

70. The HDL play a major role in:a) Transport of phospholipids to the tissues

b) Synthesis of triacylglycerol

c) Delivary of apoprotein B100 to VLDLd) Transport of cholesterol from the tissues to the liver

e) Storage of apoproteins


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a) Isoleucine and Serine

b) Histidine and Alanine

c) Cysteine and Valine

d) Aspartate and Glycine

e) Valine and Isoleucine

4. The following amino acids contain two carboxylic groups:a) D and E

b) Q and Y

c) A and K

d) C and M

e) H and R

5. Positively charged amino acids are:a) P and R

b) L and T

c) K and R

d) H and M

e) N and F

6. The primary structure of proteins:a) Refers to the sequence of amino acids in the polypeptide chainb) Refers to the helical structure of the protein

c) Describes the beta-pleated sheets

d) Is maintained by hydrogen bonds

e) Is maintained by hydrophobic interactions

7. Denaturation of a protein involves loss of its:a) Primary structure

b) Secondary & Tertiary structure

c) Primary & Tertiary structure

d) Primary & Quaternary structure

e) Amino acids

8. The alpha helix in a protein:

a) Refers to its tertiary structureb) Is not affected by amino acid sequence

c) Is stabilized by covalent bonds

d) Refers to its secondary structuree) Is the quaternary structure

9. Glycoproteins contain sugar residues covalently bonded to:a) Lysine

b) Methionine

c) Leucine

d) Asparagine

e) Cysteine

10. The following amino acids contain two carboxylic groups:


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a) Aspartate and Glutamate

b) Asparagines and Glutamine

c) Glutamine and Aspartate

d) Proline and Glutamate

e) Glycine and Methionine

11. Positively charged amino acids are:a) Valine and Arginine

b) Leucine and Lysine

c) Lysine and Arginine

d) Histidine and Cystine

e) Arginine and Glutamine

12. Sulphur containing amino acids:a) Are non-polar

b) Include cysteine and methioninec) Are involved in disulphide bridges

d) Are involved in methyl group donation

e) Are non essential amino acids

13. The alpha helix in a protein:a) Describes the secondary structureb) Is stabilized by peptide bonds

c) Stabalized by hydrogen bonds between NH and CO main chain groups

d) Is the basis for quaternary structure formation

e) Dictates its tertiary structure

14. The following are classified as acidic amino acids:

a) H and Rb) D and Ec) E and Y

d) A and K

e) C and D

15. Albumin is an important carrier of:a) Fatty acids and glucose

b) Hyroxine and glycerol

c) Bilirubin and calcium

d) Ammonia and urea

e) Lactate and bilirubin

16. Hemoglobin and myoglobin have the same:a) Oxygen affinity

b) Primary structure

c) Quaternary structure

d) Prosthetic groupe) Molecular weight

17. The branched chain amino acids:a) Are isoleucine and serine

b) Include histidine and valinec) Undergo transamination and oxidative decarboxylation by similar reactions

d) Are valine, aspartate and glycine


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b) Are non-essential amino acids

c) Can be synthesized from serine

d) Are always found at the carboxy terminal of the polypeptide chain


26. Albumin is:a) Synthesized in the liver

b) Water-soluble protein

c) A carrier of bilirubin and calcium

d) Decreased in blood and in protein calorie malnutrition

e) All of the above

27. Hemoglobin S:a) Results from insertion of a nucleotide

b) Results from substitution mutation

c) Is incompatible with life

d) The deficiency manifest in all children of carrier parents

e) Has the same affinity for oxygen as hemoglobin F

28. All of the following are considered "weak interactions" in proteins except:a) Van der Waals force

b) Hydrogen bonds

c) Ionic bonds

d) Peptide bondse) Hydrophobic interactions

29. Hemoglobin:a) Has a quaternary structure

b) Contains porphyrin ringc) Contribute to pH maintenance in blood

d) Affinity towards oxygen increases with cooperativity


30. Globular proteins:a) Are structural proteinsb) Include peptide hormones

c) Are always found in the plasma membrane

d) Are relatively water insoluble

e) Are always glycosylated

31. The following are peptides:a) Glutathione and vasopressin

b) Gramicidin and tyrosine

c) Vasopressin and epinephrine

d) Ceramide and endorfens

e) Guanosine and insulin

32. Glycoproteins contain sugar residues covalently boded to:a) Threonine and serine

b) Leucine and arginine

c) Asparagine and glycined) Cysteine and histidine

e) Lysine and methionine


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33. The following is true about amino acids:a) Cysteine and serine are polar unchargedb) Methionine can form a cross link between peptides

c) Histidine and glutamic acid are negatively charged

d) Glycine has D and L isomers

e) Tyrosine is a basic amino acid

34. Enzymes involved in protein digestion are mainly produced by:a) Stomach

b) Duodenum

c) Jejunum

d) Ileum

e) Pancreas

35. Glycoproteins contain sugar residues covalently boded to:a) Lysine

b) Threoninec) Leucine

d) Asparagine

e) Cysteine

36. The following amino acids have nonpolar side chains:a) Valine and serine

b) Methionine and leucine

c) Arginine and alanine

d) Glycine and asparagine

e) Isoleucine and valine

37. The following is true about amino acids:a) Ornithine is alpha amino acid

b) Gl

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