MS II Practice Exam

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Practice for MS II exam


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  • 1. 
    Which of the following nerves of the lumbar and lumbosacral plexus is formed by the most superior (rostral) segments:
    • A. 

      Tibial

    • B. 

      Femoral

    • C. 

      Sciatic

    • D. 

      Lumbrosacral Trunk

    • E. 

      Pudendal

  • 2. 
    Which of the following nerves of the lumbar and lumbosacral plexus is matched correctly:
    • A. 

      Obturator–lateral thigh –adduction –L3L4

    • B. 

      Femoral –anterior thigh –patellar reflex –leg extension

    • C. 

      Tibial –posterior leg (calf) –ankle reflex –plantar extension

    • D. 

      Lateral femoral cutaneous–lateral thigh –abduction –L4L5

    • E. 

      Deep peroneal –anterior leg –foot drop –L5

  • 3. 
    Which of the following nerves DOES NOT contain sensory fibers distal to the patella?
    • A. 

      Femoral Nerve

    • B. 

      Sciatic Nerve

    • C. 

      Deep Peroneal Nerve

    • D. 

      Obturator Nerve

    • E. 

      Tibial Nerve

  • 4. 
    Macrophages can have which of the following effects:
    • A. 

      Release histamine in response to inflammation

    • B. 

      Degrade extracellular matrix proteins

    • C. 

      Responds to cytokines by activating transcription growth factors

    • D. 

      Contains the largest ER of all connective tissue cells

    • E. 

      Contain antigen presenting proteins

  • 5. 
    Which of the following is NOT a major tissue type of connective tissue:
    • A. 

      Fibroblasts

    • B. 

      Mast Cells

    • C. 

      Macrophages

    • D. 

      Lymphocytes

    • E. 

      Collagen IV

  • 6. 
    Choose the one answer that correctly describes a feature of epithelia:
    • A. 

      Blood vessels and lymphatics are present within epithelia

    • B. 

      Type I collagen is deposited between epithelial cells

    • C. 

      The basal layer of epithelium adheres to the basement membrane

    • D. 

      Fibrosis occurs within the epithelium.

    • E. 

      Fibrosis occurs within the epithelium

  • 7. 
    Which function is NOT attributable to macrophages:
    • A. 

      Phagocytosis

    • B. 

      Type I collagen synthesis

    • C. 

      Antigen presentation

    • D. 

      Cytokine secretion

  • 8. 
    Which collagen is found within basement membranes but not connective tissues?
    • A. 

      Type I, a fibrillar collagen

    • B. 

      Type III

    • C. 

      Type IV, a network forming collagen

    • D. 

      Fibril associated collagens (e.g. Type IX)

  • 9. 
    Which of the following peptidases is the most important in protein digestion?
    • A. 

      Carboxypeptidase

    • B. 

      Trypsin

    • C. 

      Chymotrypsin

    • D. 

      Elastase

    • E. 

      Aminopeptidase

  • 10. 
    Which of the following transporters moves amino acids to the portal system?
    • A. 

      Facilitated Amino Acid Transporters

    • B. 

      γ-glutamyltranspeptidase

    • C. 

      Na+-dependent amino acid transporters

    • D. 

      Na+,K+-pump

  • 11. 
    In which of the following tissues protein turnover has the fastest rate?
    • A. 

      Liver

    • B. 

      Kidney

    • C. 

      Brain

    • D. 

      Small Intestine

    • E. 

      Skeletal Muscle

  • 12. 
    Which of the following is NOT an endopeptidase?
    • A. 

      Carboxypeptidase

    • B. 

      Chymotrypsin

    • C. 

      Trypsin

    • D. 

      Pepsin

  • 13. 
    Which of the following classifications would best describe the type of connective tissue in Curt Schillings injury?
    • A. 

      Loose connective tissue

    • B. 

      Dense Irregular Connective Tissue

    • C. 

      Dense Regular Connective tissue

  • 14. 
    Collagen processing is tightly regulated at multiple “levels”in cells. Review the following list of statements and choose the one that is incorrect:
    • A. 

      Collagen I expression is regulated in part by transcriptional controls.

    • B. 

      Proper assembly ofprocollagen requires hydroxylation ofprolines.

    • C. 

      Collagen fibers are assembled in the rough endoplasmic reticulum

    • D. 

      One variant of EhlersDanlos Syndrome has two known lesions: one is dominant negative and involves the peptide sequence that is normally cleaved and resides in the N-terminal propeptide. The other, autosomal recessive, results from a defect in the enzyme that cleaves this peptide.

    • E. 

      Fibrillar and fibril-associated collagens are two distinct groups of collagens

  • 15. 
    Marfan syndrome is an autosomal dominant disorder with defects in the ocular, skeletal and cardiovascular systems.  Cardiovascular abnormalities are life-threatening and include dilation of the ascending aorta.  What would you suspect is the cause of this disorder?
    • A. 

      Overproduction of type I collagen.

    • B. 

      Improper assembly of elastic fibers

    • C. 

      Decreased elastin production.

    • D. 

      Increased hyaluronan deposition

  • 16. 
    Which of the following plays the most critical role in the stability of the collagen triple helix?
    • A. 

      Hydroxylation

    • B. 

      Glycosylation

    • C. 

      Hydroxyproline

    • D. 

      Procollagen-N

  • 17. 
    Which of the following statements is correct?
    • A. 

      Protein turnover leads to hydrolysis and resynthesis of approximately 56 g of body protein each day.

    • B. 

      Amino acids in excess of biosynthetic needs are stored as proteins.

    • C. 

      An aminotransferase reaction using alanine and alpha-ketoglutarate yields glutamate and oxaloacetateas products.

    • D. 

      Urea is quantitatively the most important nitrogen-containing compound in urine.

    • E. 

      Glutamine is not found in tissue proteins

  • 18. 
     Which of the following statement concerning glutamine is INCORRECT?
    • A. 

      Glutamine is found in tissue proteins.

    • B. 

      The only fate of glutamine is hydrolysis to glutamate and ammonia.

    • C. 

      Glutamine is responsible for the transport of ammonia in non-toxic form.

    • D. 

      ATP is required for synthesis of glutamine from glutamate and ammonia

    • E. 

      In liver glutamine is hydrolyzed to glutamate and ammonia.

  • 19. 
    Mutation in the which of the following enzymes of the urea cycle causes arginemia?
    • A. 

      Carbomoyl phosphate synthetase

    • B. 

      Ornithine transcarbomoylase

    • C. 

      Arginase

    • D. 

      Arginosuccinate synthetase

    • E. 

      None of the above

  • 20. 
    In which of the following tissues glucose-alanine cycle is a major route for ammonia detoxification?
    • A. 

      Kidney

    • B. 

      Liver

    • C. 

      Gut

    • D. 

      Brain

    • E. 

      Skeletal Muscle

  • 21. 
    Which of the following chemical reactions is the rate-limiting in the urea cycle?
    • A. 

      NH++ CO+ 2 ATP --> carbomoyl phosphate

    • B. 

      Ornithine + carbomoyl phosphate --> citrulline.

    • C. 

      Citrulline+ aspartate --> arginocuccinate

    • D. 

      Arginosuccinate --> arginine + fumarate.

    • E. 

      Arginine --> urea + ornithine

  • 22. 
    Which of the following enzymes is responsible for brain metabolic deficits in hyperammonemia?
    • A. 

      Arginosuccinate lyase

    • B. 

      Aspartate Amino Transferase

    • C. 

      Glutamate dehydrogenase

    • D. 

      Alanine aminotransferase

    • E. 

      Glutaminase

  • 23. 
    Which of the following is synthesized from an essential amino acid?
    • A. 

      Alanine

    • B. 

      Glutamate

    • C. 

      Proline

    • D. 

      Tyrosine

    • E. 

      Aspartate

  • 24. 
    Select a correct answer.  Two exclusively ketogenic amino acids are:
    • A. 

      Glutamine and glutamate

    • B. 

      Leucine and lysine

    • C. 

      Tyrosine and isoleucine

    • D. 

      Leucine and isoleucine

    • E. 

      None of the above

  • 25. 
    Metabolism of which of the following amino acids is defective in maple syrup urine disease?
    • A. 

      Tryptophan

    • B. 

      Tyrosine

    • C. 

      Aromatic amino acids

    • D. 

      Branched chain amino acids

    • E. 

      Phenylalanine

  • 26. 
    Which of the following cofactors is important in reactions of transamination?
    • A. 

      Pyridoxal

    • B. 

      Pryidoxine

    • C. 

      Coblamine

    • D. 

      Pryidoxal phosphate

    • E. 

      Carbomoyl phosphate

  • 27. 
    Which of the following cofactors is important in the reactions involving one carbon transfer group
    • A. 

      Tetrahydrobiopterin

    • B. 

      Pyridoxal phosphate

    • C. 

      Tetrahydrofolate

    • D. 

      Acetyl-CoA

    • E. 

      None of the above

  • 28. 
    Excess Tryptophan in the diet will have all of the following effects EXCEPT:
    • A. 

      Induction of tryptophan oxygenase

    • B. 

      Stabilization of tryptophan oxygenase, tyrosine transaminase, and ornithine aminotransferase

    • C. 

      Allosteric effector on tryptophan oxygenase

    • D. 

      Allosteric effects on NAc-glutamate and urea formation.

    • E. 

      Increase in gluconeogenesis by stabilization of PEP-carboxykinase

  • 29. 
    Select the Tissue where glucose DOES NOT serve as a preferential energy substrate after the meal
    • A. 

      Brain

    • B. 

      Skeletal Muscle

    • C. 

      Gut

    • D. 

      Kidney

    • E. 

      Blood immune cells

  • 30. 
    Select the tissue where glutamine is used for pH regulation
    • A. 

      Brain

    • B. 

      Skeletal Muscle

    • C. 

      Gut

    • D. 

      Blood immune cells

    • E. 

      Kidney

  • 31. 
    Select the tissue where glutamine is used as a preferential substrate for the energy need and nucleotide synthesis in sepsis.
    • A. 

      Brain

    • B. 

      Skeletal Muscle

    • C. 

      Gut

    • D. 

      Kidney

    • E. 

      Blood Immune Cells

  • 32. 
    Select the tissue where branched chain amino acids serve as the major soure of energy substrates during fasting.
    • A. 

      Brain

    • B. 

      Skeletal Muscle

    • C. 

      Gut

    • D. 

      Kidney

    • E. 

      Blood Immune Cells

  • 33. 
    Which of the following would be an example of paracrine signaling?
    • A. 

      Growth factors produced by epidermis that stimulate keratinocytes

    • B. 

      A growth-promoting factor produced by fibroblasts that regulates epidermal cells.

    • C. 

      Mechanical signals affecting epidermal and connective tissue cells

    • D. 

      A factor produced only by macrophages

  • 34. 
    Which of the following blood vessel structures mediate plasma protein extravasation
    • A. 

      Arterioles

    • B. 

      Veins

    • C. 

      Capillary shunts

    • D. 

      Post-capillary venules

    • E. 

      The adventitial layer

  • 35. 
    From the following list, which one is the most important reason that the epithelium must be restored promptly following injury?
    • A. 

      It signals neutrophils to emigrate from vessels

    • B. 

      It protects the wound from UV damage

    • C. 

      The epidermis is solely responsible for regulating wound macrophage function

    • D. 

      It protects the wound from infection

  • 36. 
    What common chemical reaction is used in synthesis of GABA, histamine, and serotonin?
    • A. 

      Transamination

    • B. 

      Oxidative deamination

    • C. 

      Decarboxylation

    • D. 

      Methylation

    • E. 

      Hydroxylation

  • 37. 
    Which of the following amino acid derivatives are stress hormones
    • A. 

      Melatonin and histamine

    • B. 

      Dopamine and glutamate

    • C. 

      Histamine and norepinephrine

    • D. 

      Epinephrine and serotonin

    • E. 

      Norepinephrine and dopamine

  • 38. 
    Physiological functions of nitric oxide include:
    • A. 

      Vasodilation and stimulation of gastric acid release

    • B. 

      Neurotransmission and regulation of liver metabolism

    • C. 

      Stimulation of bile acid release and neuromodulation

    • D. 

      Neurotransmission and vasodilation

    • E. 

      None of the above

  • 39. 
    Which of the following is the precursor to developed bone tissue?
    • A. 

      Fibrous Cartilage

    • B. 

      Elastic Cartilage

    • C. 

      Hyaline Cartilage

    • D. 

      Articular Cartilage

    • E. 

      SOX9

  • 40. 
    A mutation in the gene that encodes the protein Sox9 will cause all of the following EXCEPT:
    • A. 

      Angulation of long bones

    • B. 

      Decrease in the number of ribs

    • C. 

      Craniofacial abnormalities

    • D. 

      Abnormalities in the vertebral column

    • E. 

      Missing limb(s)

  • 41. 
    Which of the following cells is NOT involved in modulation?
    • A. 

      Osteoclasts

    • B. 

      Osteocytes

    • C. 

      Osteoblasts

    • D. 

      Progenitor Cells

  • 42. 
    Which of the following collagen biosynthetic processes occur outside fibroblasts?
    • A. 

      MRNA translation on ribosomes

    • B. 

      Cross-linking by lysyl oxidase

    • C. 

      Cleavage of N- and C- terminal propeptides

    • D. 

      Hydroxylation of Pro- and Lys- residues

  • 43. 
    Which of the following enzymes would most likely be mutated in a patient suffering from Lesch-Nyhan Syndrome?
    • A. 

      Hypoxanthine-guanine phosphoribosyl transferase

    • B. 

      Purine nuceoside phosphorylase

    • C. 

      Orotate phosphoribosyltransferase

    • D. 

      Adenosine deaminase

  • 44. 
    Which enzyme catalyzes the committed step in de novo purine synthesis?
    • A. 

      GMP Synthase

    • B. 

      PRPP Synthase

    • C. 

      PRPP Glutamyl amidotransferase

    • D. 

      Adenylosuccinate synthetase

    • E. 

      IMP dehydrogenase

  • 45. 
    How many ATPs are consumed during the conversion of PRPP --> IMP?
    • A. 

      1

    • B. 

      2

    • C. 

      3

    • D. 

      4

    • E. 

      5

  • 46. 
    What additional biochemically relevant molecule is produced during the synthesis of AMP?
    • A. 

      Aspartate

    • B. 

      Glutamate

    • C. 

      Asparagine

    • D. 

      Fumarate

    • E. 

      Citrate

  • 47. 
    Uric acid levels increase in Lesch-nyhan patients because:
    • A. 

      PRPP activates PRPP amidotransferase

    • B. 

      Deficient salvage of purine bases

    • C. 

      PRPP concentrations increase

    • D. 

      All of the above

    • E. 

      None of the above

  • 48. 
    The cement layer of an osteon secretes which of the following proteins:
    • A. 

      Osteoprotegerin

    • B. 

      Osteopontin

    • C. 

      Osteocalcin

    • D. 

      Osteonectin

  • 49. 
    What region in the epiphyseal plate is most proximal to the epiphysis?
    • A. 

      Proliferative Zone

    • B. 

      Maturation Zone

    • C. 

      Secondary Spongiosa

    • D. 

      Degeneration Zone

    • E. 

      Reserve Zone

  • 50. 
    Which of the following enzymes are not heavily regulated during pyrimidine synthesis?
    • A. 

      PRPP Synthase

    • B. 

      CPS II

    • C. 

      Aspartate transcarbamoylase

    • D. 

      CTP synthase

  • 51. 
    Salvage of all of the following involve PRPP transferase EXCEPT:
    • A. 

      Thymine

    • B. 

      Uridine

    • C. 

      Adenine

    • D. 

      Guanine

    • E. 

      Cytosine

  • 52. 
    Excess dATP inhibits the de novo synthesis of dTMP by:
    • A. 

      Inhibiting the reduction of UDP to dUDP and of CDP to dCDP

    • B. 

      Inhibiting thymidylate synthase

    • C. 

      Inhibiting aspartate transcarbamoylase

    • D. 

      Inhibiting thymidine kinase

  • 53. 
    Inhibition of dihydrofolate reductase results in reducing the intracellular concentration of:
    • A. 

      10-formyltetrahydrofolate

    • B. 

      5, 10- methylenetetrahydrofolate

    • C. 

      5, 10- methenyltetrahydrofolate

    • D. 

      All of the above

    • E. 

      None of the above

  • 54. 
    Which of the following best describes uridine:
    • A. 

      It is a nucleotide that is used to treat orotic aciduria and can feedback inhibit carbamoyl phosphate synthetase II

    • B. 

      It is a nucleoside that is used to treat orotic aciduria and is converted by kinases into the nucleoside mono-, di-, and triphosphate forms.

    • C. 

      It is the direct precursor to thymidylate

    • D. 

      It is a base which is salvaged to make uridylate (UMP)

  • 55. 
    Which of the following IS NOT involved in the salvage and conversion pathway of thymine to dTTP
    • A. 

      PRPP phosphoribosyl transferase

    • B. 

      Nucleoside phosphorylase

    • C. 

      Thymidine kinase

    • D. 

      Thymidylate kinase

  • 56. 
    Which of the following best describes carbamoyl phosphate synthase II:
    • A. 

      It is the key enzyme for de novo pyrimidine biosynthesis that is regulated in prokaryotes

    • B. 

      It is found in the MT and participates in the urea cycle

    • C. 

      It is inhibited by CTP and orotate

    • D. 

      It is part of a multifunctional polypeptide and activated by PRPP

  • 57. 
    Which of the following correctly describes the differences between degradation pathways of AMP and dAMP
    • A. 

      AMP degradation pathway solely depends on adenosine deaminase

    • B. 

      AMP but not dAMP degradation eventually produces uric acid

    • C. 

      AMP degradation pathway solely depends on adenylate deaminase

    • D. 

      DAMP degradation pathway depends on adenosine deaminase not adenylate deaminase

  • 58. 
    Which of the following describes the biochemical role or fate of dUDP:
    • A. 

      It is converted to dUTP, which activates purine reduction by binding to a ligand binding site of ribonucleotide reductase

    • B. 

      It is converted to dUTP, which is one intermediate in the pathway for thymidylate synthesis

    • C. 

      It is converted to dUTP, which feedback inhibits the reduction of pyrimidines by binding to a ligand binding site of ribonucleotide reductase

    • D. 

      It is rapidly degraded to avoid the incorporation of dUTP into DNA

  • 59. 
    Lower levels of PRPP glutamyl amidotransferase activity would be expected to occur in:
    • A. 

      Lesch-nyhan patients defective in hypoxanthine guanine phosphoribosyl transferase compared to healthy individuals

    • B. 

      Gout patients after treatment with allopurinol

    • C. 

      Gout patients that over produce PRPP, compared to healthy individuals

    • D. 

      Gout patients after treatment with uricosuric drugs

  • 60. 
    What is the prevalent cause of gout?
    • A. 

      Over-production of uric acid

    • B. 

      Genetic defects in nucleotide metabolism

    • C. 

      Under-excretion of uric acid

    • D. 

      Treatment with chemotheraputic agents.

  • 61. 
    What is the definitive diagnosis for gout?
    • A. 

      Hyperuricemia

    • B. 

      Inflammation of the big toe

    • C. 

      Presence of uric acid crystals at the site of inflammation

    • D. 

      Precense of bone deformities at the site of inflammation

  • 62. 
     5-methyl tetrahydrofolate would be expected to accumulate in patients lacking or deficient in:
    • A. 

      Vitamin b12

    • B. 

      Methylene tetrahydrofolate reductase

    • C. 

      Dihydrofolate reductase

    • D. 

      Serine hydroxylmethyl transferase

  • 63. 
    Inhibition of dihrodrofolate reductase would lead to lower concentrations of all the following except:
    • A. 

      CTP

    • B. 

      Purine nucleotides

    • C. 

      THF

    • D. 

      DTMP

  • 64. 
    Which of the following is true concerning transfer of one carbon from tetrahydrofolate derivates:
    • A. 

      CO2 can be transferred by THF

    • B. 

      5-methyl tetrahydrofolate is used to transfer one carbon groups to dUMP to make thymidylate and tetrahydrofolate

    • C. 

      10-formyl tetrahydrofolate is used in the synthesis of methionine

    • D. 

      5, 10 methylene-THF is used to transfer a one carbon group to dUMP and results in the formation of dihydrofolate and thymidylate

  • 65. 
    What is the regulatory role of inosine monophosphate (IMP)
    • A. 

      Feedback inhibition of adenylosuccinate synthase

    • B. 

      Activation of inosine dehydrogenase

    • C. 

      Inhibition of PRPP glutamyl amidotransferase

    • D. 

      Activation of carbamoyl phosphate synthetase