Microbiology 020 - General Microbiology » Winter 2022 » Lab Quiz 4-Selective & Differential Media

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Question #1
After inoculation, if MSA turns ______, the presumptive ID is ______.
A.   Red; Non-coliform
B.   Red; Staphyloccus aureus
C.   Yellow; Staphylococcus aureus
D.   Yellow; Coliform
E.   Red; Coliform
Question #2
On an MSA plate, if the bacterium ferments mannitol, _____ is produced, and the indicator dye turns _____.
A.   Base; yellow
B.   Water; orange
C.   Acid; yellow
D.   Base; red
E.   Acid; red
Question #3
Is MacConkey agar selective, differential, both, or neither.
A.   Neither
B.   Selective only
C.   Differential only
D.   Selective & Differential
Question #4
When bacteria grown on EMB and produce a black color with a metallic sheen, the presumptive ID is ______.
A.   Staphylococcus
B.   Gram +
C.   Probable coliform
D.   Possible coliform
E.   Non-coliform
Question #5
Is EMB selective, differential, both, or neither?
A.   Neither
B.   Differential only
C.   Selective & Differential
D.   Selective only
Question #6
A transparent halo surrounding bacterial growth on a starch hydrolysis plate indicates that the bacterial species is _____.
A.   Ferments lactose
B.   Is a strict aerobe
C.   Is a facultative halophile
D.   Amylase +
Question #7
Is the catalase test selective, differential, both, or neither?
A.   Selective only
B.   None
C.   Selective & Differential
D.   Differential only
Question #8
A positive oxidase test will appear _____.
A.   Bubbly upon adding the reagent
B.   Blue, 60 seconds after adding the reagent
C.   Clear, between 0 and 60 seconds after adding the reagent
D.   No bubbles upon adding the reagent
E.   Blue, between 0 & 60 seconds after adding the reagent
Question #9
On blood agar, streptolysin O expresses maximal activity under _____ conditions.
A.   Microaerophilic
B.   Facultative
C.   Anaerobic
D.   Aerobic
Question #10
Is blood agar selective, differential, both, or neither?
A.   Differential only
B.   Selective & Differential
C.   Neither
D.   Selective only

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