Microbiology 2420 :Lab Exam 2
Questions Answered Correctly.
Does the plastic petri plate lid provide any protection against UV radiation? - Answer yes
How was the effect of UV irradiation measured in the laboratory? - Answer decrease in
colony number
Which species of bacteria would be most resistant to UV irradiation as measured by colony
formation? - Answer Bacillus subtilis
Which of the following is not a characteristic of the 3+1 inoculation technique? - Answer
Enables the selection of individual colonies
How is the zone of inhibition measured? - Answer diameter
What method was used to test for antibiotic susceptibility? - Answer Kirby-Bauer test
If a microbiology lab student left safranin out of the Gram stain procedure, what would be the
result? - Answer Gram-positive cells would be purple and Gram-negative cells would be
colorless
All of the following are common to both the Gram stain and the acid-fast EXCEPT - Answer a
chemical mordant
Safranin dye is used as a counterstain in _________ stain(s). - Answer both the Gram and the
endospore
Heat is used to drive the stain into cells in the _____ staining procedure(s). - Answer both
acid-fast and endospores stains
Carbolfuchsin is the ______ in the acid-fast stain - Answer primary stain
Which of the following classification methods relies on the morphology of organisms? - Answer
physical charcteristics
The Gram stain works because of differences in the ______ of bacteria. - Answer cell walls
, In the Gram stain procedure, iodine serves as a - Answer mordant
What role does safranin play in the Gram stain procedure? - Answer counterstain
In Gram staining, ethanol-acetone is used as a - Answer decolorizing agent
Acidic dyes are commonly used for ______ stains. - Answer negative
The ______ stain makes use of malachite green - Answer endospore
Which one of these Gram positive organisms makes spores? - Answer Bacillus
Which of the following is the most difficult to inactivate? - Answer bacterial endospores
Alcohols are used for - Answer both antisepsis and disinfection
What is the name of the tube used to detect gas production in carbohydrate fermentation
tubes? - Answer Durham tube
Which term below describes a colony elevation? - Answer umbonate
Which term below describes a colony form or pattern? - Answer circular
Which term below does not describe surface growth characteristic in broth media? - Answer
flaky
A microbe that grows only at the bottom of a tube of thioglycollate medium is probably a(n) -
Answer obligate anaerobe
At temperatures higher than the maximum growth temperature for an organism - Answer
hydrogen bonds are broken, proteins are denatured, and membranes become too fluid
What Gram reaction would you expect for coliform bacteria, e.g. E.coli? - Answer negative
Which carbohydrate fermentation broth are coliforms known to ferment? - Answer sucrose
Questions Answered Correctly.
Does the plastic petri plate lid provide any protection against UV radiation? - Answer yes
How was the effect of UV irradiation measured in the laboratory? - Answer decrease in
colony number
Which species of bacteria would be most resistant to UV irradiation as measured by colony
formation? - Answer Bacillus subtilis
Which of the following is not a characteristic of the 3+1 inoculation technique? - Answer
Enables the selection of individual colonies
How is the zone of inhibition measured? - Answer diameter
What method was used to test for antibiotic susceptibility? - Answer Kirby-Bauer test
If a microbiology lab student left safranin out of the Gram stain procedure, what would be the
result? - Answer Gram-positive cells would be purple and Gram-negative cells would be
colorless
All of the following are common to both the Gram stain and the acid-fast EXCEPT - Answer a
chemical mordant
Safranin dye is used as a counterstain in _________ stain(s). - Answer both the Gram and the
endospore
Heat is used to drive the stain into cells in the _____ staining procedure(s). - Answer both
acid-fast and endospores stains
Carbolfuchsin is the ______ in the acid-fast stain - Answer primary stain
Which of the following classification methods relies on the morphology of organisms? - Answer
physical charcteristics
The Gram stain works because of differences in the ______ of bacteria. - Answer cell walls
, In the Gram stain procedure, iodine serves as a - Answer mordant
What role does safranin play in the Gram stain procedure? - Answer counterstain
In Gram staining, ethanol-acetone is used as a - Answer decolorizing agent
Acidic dyes are commonly used for ______ stains. - Answer negative
The ______ stain makes use of malachite green - Answer endospore
Which one of these Gram positive organisms makes spores? - Answer Bacillus
Which of the following is the most difficult to inactivate? - Answer bacterial endospores
Alcohols are used for - Answer both antisepsis and disinfection
What is the name of the tube used to detect gas production in carbohydrate fermentation
tubes? - Answer Durham tube
Which term below describes a colony elevation? - Answer umbonate
Which term below describes a colony form or pattern? - Answer circular
Which term below does not describe surface growth characteristic in broth media? - Answer
flaky
A microbe that grows only at the bottom of a tube of thioglycollate medium is probably a(n) -
Answer obligate anaerobe
At temperatures higher than the maximum growth temperature for an organism - Answer
hydrogen bonds are broken, proteins are denatured, and membranes become too fluid
What Gram reaction would you expect for coliform bacteria, e.g. E.coli? - Answer negative
Which carbohydrate fermentation broth are coliforms known to ferment? - Answer sucrose
