Biochemistry

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Biochemistry Questions MOLECULAR 1.

Which histone is not part of the nucleosome core? (p. core? (p. 66) ________________________________ 66) ________________________________

2.

What is DNA called when it is condensed and transcriptionally inactive? (p. 66) _______________ 66) _______________

3.

What is the name for transcriptionally active DNA? (p. 66) _________________________________  _________________________________

4.

What physical property is displayed by nucleic acids that have increasing proportions of guaninecytosine bonds? (p. 67) ___________________________________________________________ 67) ___________________________________________________________

5.

Which molecule is yielded by deamination of cytosine? (p. 67) _____________________________  _____________________________

6.

Which enzyme is inhibited by hydroxyurea? (p. 68) ______________________________________ 68) ______________________________________

7.

5-Fluorouracil inhibits _______________, whereas both methotrexate and trimethoprim inhibit  _______________. (p. 68)

8.

A child has megaloblastic anemia not responsive to vitamin B12  or folate administration. She is small for her age. Serum studies show increased orotic acid and a normal ammonia level. What is the most likely diagnosis? (p. 68) ____________________________________________________ 68) ____________________________________________________

9.

A child has megaloblastic anemia not responsive to vitamin B12  or folate administration. She is small for her age. Serum studies show increased orotic acid and hyperammonemia. What is the most likely diagnosis? (pp. 68, 105) __________________________________________________ 105) __________________________________________________

10.

A 12-year-old boy with moderate mental retardation visits his physician physician because of painful swollen  joints. During th e examination, t he boy makes several uncontrolled spastic muscle movements. His medical history includes muscular hypotonia diagnosed when he was 5 months old. When he was 3 years old he was referred to a pediatric dentist for severe repetitive biting of his lip and tongue. What is the most likely diagnosis? (p. 69) _____________________________________________ 69) _____________________________________________

11.

Silent mutations often result from changes changes in which position of of a codon? (p. 69) _______________ 69) _______________

12.

What kind of mutation denotes a DNA change that results in the misreading of all nucleotides nucleotides downstream from it? (p. 69) ________________________________________________________ 69) ________________________________________________________

13.

What enzyme has exonuclease activity in prokaryotic DNA replication? (p. 70)  70)  ________________

14.

What enzyme degrades the RNA primer and replaces it with DNA during prokaryotic DNA replication? (p. 70) _______________________________________________________________ 70) _______________________________________________________________

15.

Which category of drugs inhibits DNA gyrase? (p. 70) ____________________________________ 70) ____________________________________

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16.

What specific DNA repair mechanism is defective in xeroderma pigmentosum? (p. 71) __________ 71) __________

17.

In single-stranded DNA repair, how are nucleotide-excision and base-excision repair different? (p. 71)  ___________________________________________________________________________  ______________________________________________________________________________

18.

Hereditary nonpolyposis colon cancer results from the loss of which which DNA repair mechanism? (p. 71) ___________________________________________________________________________ 71) ___________________________________________________________________________

19.

What type of RNA is the longest? The smallest? The most abundant? (p. 72) _________________ 72) _________________  ______________________________________________________________________________

20.

What commonly results from a mutation within a promoter? (p. 72) _________________________ 72) _________________________

21.

What poisonous poisonous protein that inhibits RNA polymerase II is found in death cap mushrooms? (p. 72)  ______________________________________________________________________________

22.

In eukaryotes, what enzyme makes mRNA? (p. 72) _____________________________________ 72) _____________________________________

23.

In eukaryotes, what enzyme makes tRNA? (p. 72) ______________________________________ 72) ______________________________________

24.

Patients with which disease make antibodies to spliceosomal small nuclear ribonucleoproteins? (p. 73) ___________________________________________________________________________ 73) ___________________________________________________________________________

25.

β-Thalassemia is due to a mutation causing splicing defects in a process that combines different exons within a single gene. What mechanism allows the same gene to encode for various different proteins? (p. proteins? (p. 73) _________________________________________________________________ 73) _________________________________________________________________

26.

How does tetracycline interfere with protein translation? (p. translation? (p. 74) ____________________________ 74) ____________________________

27.

How do aminoglycosides interfere with protein synthesis? (p. synthesis? (p. 75) ___________________________ 75) ___________________________

28.

Why are antibiotics such as chloramphenicol, clindamycin, and macrolides selective for bacteria and not toxic to human cells? (p. cells?  (p. 75) _________________________________________________ 75) _________________________________________________

29.

Explain the three steps of protein elongation. (p. elongation. (p. 75) _____________________________________ 75) _____________________________________  ______________________________________________________________________________  ______________________________________________________________________________

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CELLULAR 30.

Fill in the boxes boxes on the image below, noting the appropriate phases of the cell cycle. (p. 76)

31.

Which transition in the cell cycle is prevented by Rb by Rb and  and p53  p53 tumor  tumor suppressors? (p. 76) ________ 76) ________

32.

Match the cell type with its description. (p. 76)  _____ A.  _____ B.  _____ C.

Cells remain in G0 and regenerate from stem cells Enter G1 from G0 when stimulated Never go to G0 and divide rapidly with a short G 1

1. 2. 3.

Labile cells Permanent cells Stable cells

33.

Name two cells that are rich in rough endoplasmic reticulum. (p. 76) ________________________ 76) ________________________

34.

Name two cells that are rich in smooth endoplasmic reticulum. (p. 76) _______________________ 76) _______________________

35.

A child presents with coarse coarse facial features, clouded corneas, restricted joint movement, and high plasma levels of lysosomal enzymes. What is the most likely diagnosis? (p. 77) _______________ 77) _______________

36.

What syndrome syndrome results from a microtubule polymerization polymerization defect that leads leads to impaired lysosomal lysosomal emptying and poor phagocytosis? (p. 78) _____________________________________________ 78) _____________________________________________

37.

Which anticancer drug used to treat breast cancer can stabilize microtubules? (p. 78) __________ 78) __________

38.

Which antifungal agent targets microtubules? (p. 78) ____________________________________ 78) ____________________________________

39.

Which antihelminthic drugs target microtubules? (p. 78) __________________________________ 78) __________________________________

40.

A 22-year-old woman presents with a history of recurrent pneumonia. X-ray of the chest shows dextrocardia. What is the most likely diagnosis? (p. 78) __________________________________ 78) __________________________________

41.

Cilia, flagella, mitotic spindles, neurons, and centrioles are composed of of which cytoskeletal element? (p. 78) _________________________________________________________________ 78) _________________________________________________________________

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42.

Vimentin, desmin, cytokeratin, glial fibrillary acid proteins, and neurofilaments are examples of which type of cytoskeletal element? (p. 78) ____________________________________________ 78) ____________________________________________

43.

What effect does digoxin’s inhibition digoxin’s inhibition of Na -K  ATPase have on cardiac contractility? (p. 79) _____ 79) _____

+

+

 ______________________________________________________________________________ 44.

What type of collagen is found in each structure? (p. 79)  _____ A.  _____ B.  _____ C.  _____ D.

Basement membrane or basal lam ina 1. Bone, skin, tendon, dentin, fascia, c ornea, 2. late wound repair 3. Cartilage, vitreous body, nucleus pulposus 4. Skin, blood vessels, uterus, fet al tissue, granulation tissue

Type I collagen Type II collagen Type III collagen Type IV collagen

45.

British sailors in the 17th century were often unable to hydroxylate proline and lysine residues for collagen synthesis. What disease did they have, and why did the treatment work? (p. 79)  ______________________________________________________________________________

46.

What disease leads to an inability to form procollagen from pro α chains? (pp. 79, 80) __________ 80) __________

47.

A patient presents with hyperextensible skin, easy easy bruising, and hypermobile joints. What is the most likely diagnosis? (pp. 79, 80) ___________________________________________________  80) ___________________________________________________ 

48.

A baby is born with multiple fractures and hearing loss. What finding would most likely be seen during the ophthalmologic examination? (p. 80) ________________________________________ 80) ________________________________________

49.

What is the relationship between Alport's syndrome and Goodpasture's syndrome? (pp. 80, 467)  ______________________________________________________________________________

50.

Marfan's syndrome is caused by a defect in what protein? (p. 80) __________________________ 80) __________________________

51.

Which lung disorder can result from excess elastase activity? (p. 80) ________________________ 80) ________________________

LABORATORY TECHNIQUES 52.

A team of researchers is studying the mechanisms of genetic shift and genetic drift in HIV. To further the investigation, the scientists need to amplify the sequence of DNA shown. Which primer would be appropriate for use with PCR? (p. 81)

53.

Which would travel further on an agarose gel, a fragment of 10 kD or of 100 kD, and why? (p. 81)  ______________________________________________________________________________

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54.

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Describe each of the following blot techniques: Southern, Northern and Western. (p. 81) Southern blot: ___________________________________________________________________  ______________________________________________________________________________ Northern blot: __________________________________________________________________  ______________________________________________________________________________ Western blot: ___________________________________________________________________  ______________________________________________________________________________

55.

Which assay can detect single-nucleotide polymorphisms? (p. 81) __________________________ 81) __________________________

56.

What information can be obtained from an ELISA using using a test antibody   coupled to a colorgenerating enzyme? (p. 81) ________________________________________________________ 81) ________________________________________________________

57.

What is the advantage of FISH over karyotyping? (p. 82) _________________________________ 82) _________________________________  ______________________________________________________________________________

58.

A DNA fragment is added to four different different tubes along with DNA polymerase; a radiolabeled primer; and the adenine, thymine, cytosine, and guanine deoxynucleotides. Each tube also contains one of the four bases as dideoxynucleotides. The four tubes are then run on electrophoresis gel and visualized by autoradiography. Which laboratory technique does this describe? (pp. 81-82) ______ 81-82) ______  ______________________________________________________________________________

59.

Which three chromosome imbalances can be seen on a karyotype? (p. 82)  82)  __________________  ______________________________________________________________________________

GENETICS 60.

A patient has inherited a mutation in a tumor suppressor gene. Mutation of the remaining (previously normal) copy of the tumor suppressor gene represents a loss of _______________, which may lead to the development of cancer. (p. 83)

61.

A genetic genetic disease disease that shows _______________ _______________ will have mutations at different loci that produce the same phenotype. (p. 83)

62.

What is the heterozygote prevalence in a population that is in Hardy-Weinberg equilibrium? (p. 84)  ______________________________________________________________________________

63.

How is Prader-Willi syndrome inherited? What are the symptoms? (p. 84) ____________________ 84) ____________________  ______________________________________________________________________________

64.

How is Angelman’s Angelman’s syndrome  syndrome inherited? What are the symptoms? (p. 84) ____________________ 84) ____________________  ______________________________________________________________________________

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65.

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Which mode of inheritance is represented by each pedigree? (p. 85)

 _____ A.

_____ B.

 _____ D. 1. 2. 3. 4. 5.

_____ C.

_____ E.

Autosomal dominant Autosomal recessive Mitochondrial inheritance X-linked dominant X-linked recessive

66.

What percentage of sons sons of a carrier mother are expected to inherit an X-linked recessive disease? (p. 85) _________________________________________________________________________ 85) _________________________________________________________________________

67.

True or False: A mother with an X-linked dominant disease may pass the disease to her sons but not to her daughters. (p. 85) ________________________________________________________ 85) ________________________________________________________

68.

Achondroplasia is the result of a defect in which receptor? (p. 86) __________________________ 86) __________________________

69.

Adult polycystic polycystic kidney disease is inherited in an autosomal- _______________ (dominant/ recessive) pattern, whereas infantile polycystic kidney disease is associated with an autosomal _______________ (dominant/recessive) pattern. (p. 86)

70.

A patient has multiple telangiectasias and skin discolorations, and notes recurrent epistaxis. W hat other physical finding is most likely to be seen? (p. 86) _______________________________ 86) _______________________________

71.

Can refractory hereditary spherocytosis be cured? If so, how? (p. 86) _______________________ 86) _______________________

72.

A tall man comes to the emergency room with the combination of a dissecting ascending aorta and acute mitral valve prolapsed. What disorder best explains these findings? (p. 86) ______________ 86) ______________

73.

A patient has hemangioblastomas of the retina and cerebellum, as well as bilateral renal cell carcinoma. What is the most likely diagnosis? (p. 86) ____________________________________ 86) ____________________________________

74.

What renal findings might distinguish a patient with tuberous sclerosis from a patient with adult polycystic kidney disease? (p. 86) ___________________________________________________ 86) ___________________________________________________

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75.

Before his anticipated death, a 42-year-old man had received many years of treatment for depression, severe cognitive decline, and involuntary writhing movements. His father had similar symptoms shortly before his death. What is the cause of this patient’s most likely disease? likely disease? (p. 88)  ______________________________________________________________________________

76.

Cystic fibrosis results from a defect in which which gene? Which chromosome? Which ion channel? (p. 87) ___________________________________________________________________________ 87) ___________________________________________________________________________

77.

Which two pathogens are the most likely to cause recurrent pulmonary infections in a patient with cystic fibrosis? (p. 87) _____________________________________________________________ 87) _____________________________________________________________

78.

A patient patient with cystic fibrosis has an increased risk a deficiency of which four vitamins? (p. 87)  ______________________________________________________________________________

79.

A 4-year-old boy needs to use his upper upper extremities to push against his legs in order to stand up. What maneuver is he using? (p. 87) _________________________________________________ 87) _________________________________________________

80.

A male patient has a long face, a large jaw, large ears, autism, and macroorchidism. What is the most likely diagnosis? (p. 87) _______________________________________________________ 87) _______________________________________________________

81.

A newborn is diagnosed with Down syndrome. She is vomiting vomiting bilious material. What is the most likely cause? (p. 88) ______________________________________________________________ 88) ______________________________________________________________

NUTRITION 82.

Match each set of symptoms/conditions with the vitamin that is deficient. (pp. 90-94)  _____ A.  _____ B.  _____ C.

Bruising, anemia, swollen gums, and poor wound healing Cheilosis and corneal vascularization Convulsions, hyperirritability, peri pheral neuropathy, and sideroblastic anemia  _____ D. Dermatitis, enteritis, and alopecia  _____ E. Dermatitis, enteritis, alopecia, and adrenal insufficiency  _____ F. Diarrhea, dermatitis, and d ementia  _____ G. Hemolytic anemia, muscle weakness, and neuropath y  _____ H. Hemorrhagic disease of the newborn  _____ I. Hypocalecmic tetany  _____ J. Macrocytic, megaloblastic anemia with no neurologic problems  _____ K. Macrocytic, megaloblastic anemia, subacute com bined degeneration, paresthesia, and optic neuropathy  _____ L. Night blindness  _____ M. Wernicke-Korsakoff syndrome 83.

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13.

Biotin Folic acid Vitamin A Vitamin B1 Vitamin B2 Vitamin B3 Vitamin B5 Vitamin B6 Vitamin B12 Vitamin C Vitamin D Vitamin E Vitamin K

A 64-year-old 64-year-old woman is brought to her primary care physician by her son because of progressive vision loss. She had emigrated from Southeast Asia 1 week earlier. The son mentions that his mother’s poor vision worsens at night, causing her to frequently run into the bedroom wall. Physical examination shows dry conjunctivae and a small build-up of keratin debris. The patient is diagnosed with a vitamin deficiency. What other medical condition results from deficiency of a fatsoluble vitamin? (p. 93) ___________________________________________________________ 93) ___________________________________________________________

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METABOLISM 84.

Fill in the rectangles in the image below. Which steps of glycolysis are reversible (add arrows to squares)? (p. 96)

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85.

Match each of the following processes with its rate-determining enzyme. (pp. 95-96)  _____ A.  _____ B.  _____ C.  _____ D.  _____ E.  _____ F.  _____ G.  _____ H.  _____ I.  _____ J.  _____ K.  _____ L.  _____ M.

86.

page 21

Cholesterol synthesis De novo purine synthesis De novo pyrimidine synthesis Fatty acid oxidation Fatty acid synthesis Glycogen synthesis Glycolysis Gluconeogenesis Glycogenolysis HMP shunt Ketogenesis TCA cycle Urea cycle

1. Acetyl-CoA carboxylase 2. Carbamoyl phosphate synthetase I 3. Carbamoyl phosphate synthetase II 4. Carnitine acyltransferase I 5. Fructose-1,6-bisphosphatase 6. G6PD 7. Glutamine-PRPP amidotransf erase 8. Glycogen phosphorylase 9. Glycogen synthase 10. HMG-CoA reductase 11. HMG-CoA synthase 12. Isocitrate dehydrogenase 13. Phosphofructokinase-1

How many ATP molecules can be created by the metabolism of of glucose? (p. 97) ______________ 97) ______________  ______________________________________________________________________________

87.

Fill in the boxes boxes on the image below, noting the substrates of the urea cycle. (p. 105)

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88.

Fill in the boxes boxes on the image below, noting the enzymes enzymes that catalyze each each step of catecholamine synthesis. (p. 107)

89.

A 16-year-old boy presents for a routine visit. Physical examination shows shows symptoms consistent consistent with Fabry's diseases. Examination of his vascular endothelium would most likely show pathologic accumulation of which substance? (p. 111) ____________________________________________ 111) ____________________________________________

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90.

page 23

For each lysosomal storage disease in the chart below, name the enzyme and and accumulated accumulated substrate(s). (p. 111) Disease

Deficient Enzyme

Accumulated Substance(s)

Fabry’s disease Gaucher’s disease Hunter’s syndrome

Hurler’s syndrome Krabbe’s disease Metachromatic leukodystrophy Niemann-Pick disease Tay-Sachs disease

91.

Most mucopolysaccharidoses are inherited in a(n) _______________-_______________ pattern; the exception is _______________. (p. 111)

92.

Most sphingolipidoses are inherited in a(n) _______________-_______________ pattern; the exception is _______________. (p. 111)

93.

Match the lipoprotein with its function. (p. 115)  _____ A.  _____ B.  _____ C.  _____ D.  _____ E.

Delivers dietary TGs to periphera l tissues Delivers hepatic cholesterol to peripheral tissues Delivers hepatic TGs to peripheral t issues Delivers TGs and cholesterol to liver Mediates cholesterol transport fr om periphery to liver

1. 2. 3. 4. 5.

Chylomicron HDL IDL LDL VLDL

Answers MOLECULAR 1.

H1.

2.

Heterochromatin.

3.

Euchromatin. (It is less condensed and accessible to replication enzymes.)

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4.

Increasing melting temperatures due to the tighter binding of the strands.

5.

Uracil.

6.

Ribonucleotide reductase.

7.

Thymidylate synthase; dihydrofolate reductase.

8.

Orotic aciduria.

9.

Ornithine transcarbamylase deficiency. (Orotic aciduria does not have hyperammonemia.)

10.

This child has Lesch-Nyhan syndrome, syndrome, which is characterized by mental retardation, selfmutilation, aggression, hyperuricemia, gout, and choreoatheosis. It is caused by the absence of HGPRT, which leads to defective purine salvage.

11.

The third position (due to tRNA wobble).

12.

Frameshift.

13.

DNA polymerase III has 3' to 5' exonuclease activity for proofreading.

14.

DNA polymerase I.

15.

Fluoroquinolones. (They impair bacterial DNA synthesis.)

16.

Nucleotide excision repair.

17.

During nucleotide repair, the entire nucleotide nucleotide structure is removed and and replaced. During base excision repair, the base is clipped off of the sugar and repaired without the entire backbone of the DNA being taken apart.

18.

The mismatch repair system.

19.

mRNA is the longest type, type, tRNA is the smallest, and rRNA is the most abundant type of RNA.

20.

A significant decrease in gene transcription.

21.

α-Amanitin. (When consumed, it causes liver failure.)

22.

RNA polymerase II.

23.

RNA polymerase III.

24.

Lupus.

25.

Alternative splicing. (In this case, the alternative splicing yields a pathologic protein.)

26.

Tetracycline binds binds to the 30S subunit of the ribosome, blocking attachment of the aminoacyl tRNA.

27.

Aminoglycosides inhibit formation of the initiation complex, causing misreading of mRNA.

28.

They affect the 50S subunit of of the ribosome, which which is found in prokaryotic cells.

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(1) Aminoacyl-tRNA binds to the A site. (2) Peptidyltransferase adds a peptide peptide to the amino amino acid chain at site A. (3) The T he ribosome advances three nucleotides in the 3′ direction, thereby moving the peptidyl tRNA to the P site.

CELLULAR 30.

31.

Transition from G1 to S phase. (Defective cells are not allowed to undergo DNA synthesis.)

32.

A-2, B-3, C-1.

33.

Goblet cells (secrete mucus) and plasma cells (secrete antibodies).

34.

Liver hepatocytes and steroid-hormone –producing  –producing cells of the adrenal cortex.

35.

I-cell disease.

36.

Chédiak-Higashi syndrome.

37.

Paclitaxel.

38.

Griseofulvin.

39.

Mebendazole and thiabendazole.

40.

Kartagener's syndrome.

41.

Microtubule.

42.

Intermediate filaments.

43.

It increases cardiac contractility by increasing intracellular calcium concentration.

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44.

A-4, B-1, C-2, D-3.

45.

Scurvy; the limes supplied the sailors sailors with the vitamin C they needed during during their long voyage voyage (and earned them the nickname "limeys").

46.

Osteogenesis imperfecta.

47.

Ehlers-Danlos syndrome.

48.

Blue sclerae.

49.

Both are diseases of type IV collagen. (Alport's is genetic; Goodpasture's is autoimmune.)

50.

Fibrillin.

51.

Emphysema. (α1-Antitrypsin inhibits elastase, which degrades elastin; therefore, lack of α1antitrypsin can lead to loss of elastin in the lungs, thereby resulting in emphysema.)

LABORATORY TECHNIQUES 52.

ATAGTACCG; GTGCTAGTC.

53.

A fragment of 10 kD; smaller molecules travel further.

54.

Southern: DNA is run on an electrophoresis gel and transferred to a filter; the DNA on the filter is denatured and exposed to a labeled DNA probe; the double-stranded DNA is visualized when the filter is exposed to film. Northern: RNA is run on an electrophoresis gel and transferred to a filter; the RNA on the filter is exposed to a labeled DNA probe; the hybrid DNA-RNA molecule is visualized when the filter is exposed to film. Western: Sample protein is separated via gel electrophoresis and transferred to a filter; labeled antibody is used to bind the protein of interest.

55.

Microarrays.

56.

An ELISA using a test antibody can determine whether a particular antigen  antigen  is present in the patient's blood.

57.

FISH allows for identification of anomalies anomalies at a molecular level, including deletions that are too small to see on a karyotype.

58.

Sequencing.

59.

Autosomal trisomies, microdeletions, and sex chromosome disorders.

GENETICS 60.

Heterozygosity. (The patient had been a heterozygote for lost tumor suppressor suppressor gene; both genes must be lost for oncogenesis.)

61.

Locus heterogeneity.

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62.

2pq.

63.

Prader-Willi syndrome is inherited via deactivation of the paternal copies copies of genes genes on chromosome 15, or can occur via uniparental disomy. Symptoms include mental retardation, hyperphagia, obesity, hypogonadism, and hypotonia.

64.

 Angelman’s syndrome is inherited via deactivation of the maternal copies of genes on chromosome 15, or can occur via uniparental disomy. Symptoms include mental retardation, seizures, ataxia, and inappropriate laughter (“happy puppet”).

65.

A-5, B-1, C-2, D-3, E-4.

66.

50%.

67.

False. (Her sons and  daughters  daughters may be affected.)

68.

Fibroblast growth factor 3.

69.

Dominant; recessive.

70.

Arteriovenous malformations. (This constellation of symptoms is typical of hereditary hemorrhagic hemorrha gic telangiectasia.)

71.

Refractory hereditary spherocytosis can be cured by splenectomy.

72.

Marfan's syndrome. (It is associated with cystic medial necrosis of the aorta [which may lead to a dissection] as well as a floppy mitral valve prone to prolapse.)

73.

von Hippel-Lindau disease.

74.

Although both will have renal cysts, tuberous sclerosis is associated with renal angiomyolipomas.

75.

The patient has classic symptoms of Huntington’s disease, which is caused by an expansion of CAG trinucleotide repeats on chromosome 4.

76.

CF is due to a defect in the CFTR  gene  gene on chromosome 7 that affects the chloride channel.

77.

Pseudomonas species Pseudomonas species and Staphylococcus aureus.

78.

Vitamins A, A, D, E, and K (all of of which are fat soluble).

79.

Gowers’ Gowers’ maneuver. (This action (This action is necessary due to weakness of the proximal muscles.)

80.

Fragile X syndrome. (Remember: Fragile X = eX eXtra large testes, jaw, and ears.)

81.

Duodenal atresia.

NUTRITION 82.

A-10, B-5, C-8, D-1, E-7, E-7, F-6, G-12, H-13, I-11, J-2, K-9, L-3, M-4.

83.

Osteomalacia.

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METABOLISM 84.

85.

A-10, B-7, C-3, D-4, E-1, F-9, G-13, H-5, I-8, J-6, K-11, L-12, M-2.

86.

Aerobic glucose metabolism produces 32 ATP molecules per molecule of glucose in heart and liver and 30 in muscle. Anaerobic glucose metabolism products only 2 net ATP molecules per molecule of glucose.

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87.

88.

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Ceramide trihexoside.

90. Disease

Deficient Enzyme

Accumulated Substance(s)

Fabry’s disease

α-galactosidase A

Ceramide trihexoside

Gaucher’s disease

β-glucocerebrosiderase

Glucocereboside

Hunter’s syndrome

Iduronate sulfatase

Heparan sulfate, dermatan sulfate

Hurler’s syndrome

α-L-iduronidase

Heparan sulfate, dermatan sulfate

Krabbe’s disease

Galactocerebrosidase

Galactocerebroside

Metachromatic leukodystrophy

 Arylsulfatase A

Cerebroside sulfate

Niemann-Pick disease

Sphingomyelinase

Sphingomyelin

Tay-Sachs disease

Hexosaminidase A

GM2 ganglioside

91.

Autosomal-recessive; Hunter's disease.

92.

Autosomal-recessive; Fabry's disease.

93.

A-1, B-4, C-5, D-3, E-2.

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