8.  Interference mechanism of ciprofloxacin and norfloxacin is due to their action on
A.cell wall synthesis
B.cell membrane function
C.DNA function
D.protein synthesis

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9. By which of the following means antifungal chemotherapeutic agents may affect fungi?
A.Interfere with nuclear division by preventing the aggregation of microtubules needed for mitosis
B.Interfere with normal nucleic acid synthesis
C.Interfere with ergosterol biosynthesis and thus alter the structure of the cytoplasmic membrane as well as the function of several membrane-bound enzymes like those involved in nutrient transport and chitin synthesis
D.all of these

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10. Which of the following methods would be most appropriate for sterilizing an antibiotic solution?
A.Dry heat sterilization
B.Microfiltration
C.Autoclaving
D.Desiccation

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11. Which of the following drugs involves modification of the drug by enzymatic modification or degradation of its active element to alter its/their resistance?
A.Pencillins
B.Choloramphenicol
C.Aminoglyosides
D.All of these

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12. Who developed the concept of specific toxicity?
A.Pasteur
B.Fleming
C.Watson
D.Ehrlich

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13. When using alcohol as an antiseptic, which concentration is considered most effective?
A.95%
B.50%
C.70%
D.25%

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14. Fluoroquinolones are antibiotics which inhibit
A.DNA polymerase
B.RNA polymerase
C.DNA gyrase
D.Cross-linking of peptidoglycan

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