15. The "A" subunit of diphtheria toxin
A.binds host cell receptors found on heart cells
B.cause ADP ribosylation of a factor involved in protein synthesis
C.forms cAMP that leads to fluid accumulation
D.lysis macrophages with the release of cytokines

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16. Coxsackie virus B3, a subgroup of enteroviruses, commonly causes
A.acute hemorrhagic conjunctivitis
B.B. muscular dystrophy
C.myocarditis
D.gastroenteritis

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17. Prontosil is
A.an effective antibacterial when used in animals
B.an effective antibacterial when used in in-vitro cultures
C.an effective antibacterial both in animals as well as in in-vitro cultures
D.not used as an antibacterial agent

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18. All infections do not cause fever and all fevers are not due to infections which of the following is an example of non-infections cause of fever?
A.Typhoid
B.Chicken pox
C.Rheumatic disease
D.Malaria

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19. Immunization with which of the following toxoid induces high titer serum antibody, but does not protect from the corresponding disease?
A.Tetanus
B.Botulism
C.Diphtheria
D.Shigellosis

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20. Which of the following statements is not true regarding Mycobacterium tuberculosis and/or the disease it causes?
A.The pathogen contains mycolic acid in its cell wall
B.The pathogen can live inside macrophages
C.Antibodies to the pathogen are protective
D.None of these

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21. What is common in catheters and ventilators?
A.hey bypass important defenses of the body
B.Bacteria responsible for associated infections are usually susceptible to antibiotics
C.They predispose patients to viral rather than bacterial infections
D.They are used primarily in neonatal intensive care units

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