15. The archaebacterium Halobacterium, an extreme halophile, and Sulfolobus, a thermoacidophile, can be cultured in the presence of antibiotics such as streptomycin and chloramphenicol because
A.they contain ether-linked isoprenoids in their plasma membrane
B.they lack murein in their cell wall
C.they contain 80S, as opposed to 70S, ribosomes
D.all of the above

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16. The isolation of the gonorrhoea - causing organisms, Neisseria gonorrhoeae,from a clinical specimen is facilitated by the use of media containing
A.cellulose
B.certain antibiotics
C.succinate
D.none of these

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17. Anchorage -dependent cells require
A.wettable surface for growth
B.dry surface for growth
C.either (a) or (b)
D.nothing to do with the surface

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18. Stringent anaerobes can be grown in a media by taking special measure as
A.boiling the media for several minutes
B.addition of cysteine
C.passing through oxygen-free nitrogen
D.any of these

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19. Radical shifts in pH can be prevented by incorporating
A.a buffer
B.an oxidizing agent
C.a reducing agent
D.any of these

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