21. | Which of the modification in hemoglobin is the cause of sickle cell anemia? |
a. | A mutation in the beta chain |
b. | A deletion in the beta chain |
c. | Replacement of the B chain by D chain |
d. | None of the above |
View Answer Report Discuss 50-50! |
Answer: (a).A mutation in the beta chain
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22. | Klinefelter syndrome is a manifestation of which chromosome aneuploidy? |
a. | XXX |
b. | XYY |
c. | XXY |
d. | None of these |
View Answer Report Discuss 50-50! |
Answer: (c).XXY
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23. | During sickle cell anemia which of the following takes place? |
a. | Glutamine change to valine |
b. | Valine change to glutamine |
c. | Aspartic acid change to glutamic acid |
d. | Glutamic acid change to aspartic acid |
View Answer Report Discuss 50-50! |
Answer: (a).Glutamine change to valine
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24. | Methotrexate is toxic to human cells because it inhibits |
a. | formation of CTP from UTP |
b. | reduction of H2 folate to H4 folate |
c. | synthesis of PRPP |
d. | none of the above |
View Answer Report Discuss 50-50! |
Answer: (b).reduction of H2 folate to H4 folate
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25. | What is the defective enzyme in the glycogen storage Von Gierke's disease? |
a. | Phosphorylase |
b. | Phosphofructokinase |
c. | Glucose-6-phosphatase |
d. | None of the above |
View Answer Report Discuss 50-50! |
Answer: (c).Glucose-6-phosphatase
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