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MICROBIOLOGY LAB FINAL EXAM VERSION 2 EXAM LATEST 2026-
2027 ACTUAL EXAM WITH COMPLETE QUESTIONS AND CORRECT
DETAILED ANSWERS (100% VERIFIED ANSWERS) |ALREADY
GRADED A+| ||PROFESSOR VERIFIED|| ||BRANDNEW!!!||
(Phenol Red)
Fermentation of the carbohydrate (sugar) with acid end products;
gas end products. Then the organism ran out of sugar and began
degradation of the peptone; alkaline by products that bring the pH
up to produce the orange layer - ANSWER-A/G wk
(Citrate)
Color of medium before inoculation? - ANSWER-Green
(Citrate)
What pH indicator is in this medium? - ANSWER-Bromthymol
Blue
(Citrate)
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What color indicates a rise in pH from the production of alkaline or
basic products? - ANSWER-Blue
(Citrate)
What is the only source of carbon in this medium? - ANSWER-
Citrate (Sodium Citrate)
(Citrate)
What critical enzyme allows the organism to acquire carbon from
the medium? (The organism must have this molecule to utilize the
carbon source) citrate-________ - ANSWER-Permease
(Citrate)
true or false: Organisms that can't use the carbon source will not
die. - ANSWER-False
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(Citrate)
What does the organism produce when it uses the only nitrogen
source provided in the medium, and what does that do to the pH?
- ANSWER-Ammonia and ammonia hydroxide which causes an
increase in pH
(Citrate)
There is true growth not a heavy inoculum on the slant and the
slant is green. Is this a positive result for the citrate test? -
ANSWER-yes
(Mannitol Salt Agar (MSA))
For what group of organisms is the medium selecting? -
ANSWER-salt tolerant organims like Staphylococci
(Mannitol Salt Agar (MSA))
MICROBIOLOGY LAB FINAL EXAM VERSION 2 EXAM LATEST 2026-
2027 ACTUAL EXAM WITH COMPLETE QUESTIONS AND CORRECT
DETAILED ANSWERS (100% VERIFIED ANSWERS) |ALREADY
GRADED A+| ||PROFESSOR VERIFIED|| ||BRANDNEW!!!||
(Phenol Red)
Fermentation of the carbohydrate (sugar) with acid end products;
gas end products. Then the organism ran out of sugar and began
degradation of the peptone; alkaline by products that bring the pH
up to produce the orange layer - ANSWER-A/G wk
(Citrate)
Color of medium before inoculation? - ANSWER-Green
(Citrate)
What pH indicator is in this medium? - ANSWER-Bromthymol
Blue
(Citrate)
,2|Page
What color indicates a rise in pH from the production of alkaline or
basic products? - ANSWER-Blue
(Citrate)
What is the only source of carbon in this medium? - ANSWER-
Citrate (Sodium Citrate)
(Citrate)
What critical enzyme allows the organism to acquire carbon from
the medium? (The organism must have this molecule to utilize the
carbon source) citrate-________ - ANSWER-Permease
(Citrate)
true or false: Organisms that can't use the carbon source will not
die. - ANSWER-False
, 3|Page
(Citrate)
What does the organism produce when it uses the only nitrogen
source provided in the medium, and what does that do to the pH?
- ANSWER-Ammonia and ammonia hydroxide which causes an
increase in pH
(Citrate)
There is true growth not a heavy inoculum on the slant and the
slant is green. Is this a positive result for the citrate test? -
ANSWER-yes
(Mannitol Salt Agar (MSA))
For what group of organisms is the medium selecting? -
ANSWER-salt tolerant organims like Staphylococci
(Mannitol Salt Agar (MSA))
