Mini 2 Smolanoff

5 Questions

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Mini 2 Smolanoff

These are SUPER high yield. make sure you know why each wrong choice is wrong


Questions and Answers
  • 1. 
    Dr. Smolanoff One of your patients was a mechanic who worked on automobile exhaust     systems exclusively. He came in to your clinic drowsy and with pink cheeks.     He claimed that he often fainted when he exerted himself. Laboratory data     show a remarkably increased carboxyhemoglobin level in the blood. The best     explanation for this finding is that carbon monoxide
    • A. 

      Increases the hydrogen ion concentration causing oxyhemoglobin to precipitate

    • B. 

      Changes the valence state of iron in hemoglobin

    • C. 

      Competitively displaces oxygen from oxyhemoglobin.

    • D. 

      Converts myoglobin to carboxyhemoglobin at a rapid rate

    • E. 

      Prevents transfer of oxygen across the alveolar membranes

  • 2. 
    Fetal hemoglobin binds oxygen with greater affinity than adult hemoglobin due primarily to which statement?
    • A. 

      The heme iron of fetal hemoglobin is Fe3+

    • B. 

      Fetal hemoglobin binds 2 hemes per subunit

    • C. 

      Fetal hemoglobin is monomeric

    • D. 

      Fetal hemoglobin forms more salt bridges

    • E. 

      Fetal hemoglobin has a lower affinity for 2,3-BPG

  • 3. 
    A solution of equal amount of hemoglobin and myoglobin is maintained at a very low partial pressure of oxygen, so that both proteins exist predominantly in the deoxygenated form. What happens when the solution is then bubbled with a small amount of oxygen?
    • A. 

      Myoglobin undergoes a conformational change that raises its oxygen affinity above that of hemoglobin

    • B. 

      2,3BPG dissociates from hemoglobin and binds to myoglobin.

    • C. 

      Much more of the dissolved oxygen binds to myoglobin than to hemoglobin.

    • D. 

      Hemoglobin dissociates into its subunits

    • E. 

      Most of the hemoglobin becomes oxygenated while most of the myoglobin rema ins deoxygenated

  • 4. 
    Hemoglobin reversibly binds oxygen, protons, 2,3-bis-phosphoglycerate, carbon monoxide and carbon dioxide. Which statement is CORRECT concerning the nature of these bindings?
    • A. 

      Oxygen binds to Fe+3 but not to Fe+2.

    • B. 

      Hydrophobic interactions are the primary forces associated with BPG bind ing to hemoglobin

    • C. 

      When oxyhemoglobin moves to a more acidic environment, it is more apt to release its oxygen

    • D. 

      Carbon dioxide binds to Fe+2 but not to Fe+3 hemoglobin

    • E. 

      Carbon monoxide binds to Fe+3 but not to Fe+2 hemoglobin.

  • 5. 
    Dr. Smolanoff A 35 year-old women arrived at her doctor’s office concerned about her bluish skin color and was found to have a methemoglobin level of 20%. Which of the following could explain this high erythrocyte level of methemoglobin?
    • A. 

      Higher than normal levels of methemoglobin reductase

    • B. 

      Nonspherocytic hemolytic anemia

    • C. 

      Carbon monoxide poisoning

    • D. 

      Exposure to an oxidizing drug

    • E. 

      Exposure to pentachlorophenol