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Microbiology Lab Final Exam Version 1 Actual Exam
Newest Complete All Questions And Correct Detailed
Answers (Verified Answers) |Already Graded
A+|Verified!!!|Newest Version!!!!
True or false: In the environment, microbes do not self-
segregate to form uniform colonies. - Answer-True
Why do you invert petri dishes? - Answer-Condensation
can form on the lid when in the incubator. By inverting, the
condensation does not drip down onto the agar and
potentially contaminate the bacterial culture
Define sterilization and disinfection. - Answer-Sterilization:
the removal and killing of all microbes from a surface
Disinfection: the removal and killing of some microbes
from a surface
What is the reason for doing a 3 way streak? - Answer-To
get a single, pure colony
After working with S. aureus, where do you dispose of
your gloves? - Answer-Biohazard bin
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List two things that aseptic technique accomplishes -
Answer-facilitate the creation of pure microbial cultures
keep the microbes only in certain/specific places
Keep people outside the lab safe
Prevent contamination
Describe how to properly do a 3 way streak - Answer-Step
1: obtain and label TSA plate
Step 2: Sterilize loop, cool, pick up bacteria, make first
streak (keep streaks tight, want to use as much surface
area as possible)
Step 3: Rotate plate 90°, sterilize loop, cool, and pull 1-2
pulls from end of S1 and make S2
Step 4: Rotate plate 90°, sterilize loop, cool, and pull 1-2
pulls from end of S2 and make S3
What is TSA? - Answer-Tryptic soy agar (TSA): artificial
growth medium that provides adequate nutrient and
growth conditions for microbes
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Name 2 of the 5 characteristics we use to describe
nutrient agar plates. - Answer-o Size
o Pigmentation
o Form
o Margin
o Elevation
(True/False): Microbes don't self-segregate into uniform
populations. - Answer-True
Macroorganisms carry with them a panoply of natural
______ - Answer-Microflora
Name the three types of symbiotic relationships and briefly
define each - Answer-o Mutualistic-both benefit neither are
harmed
o Commensal- one benefits and the other neither benefits
or is harmed
o Parasitic-one benefits and one is harmed
Microbiology Lab Final Exam Version 1 Actual Exam
Newest Complete All Questions And Correct Detailed
Answers (Verified Answers) |Already Graded
A+|Verified!!!|Newest Version!!!!
True or false: In the environment, microbes do not self-
segregate to form uniform colonies. - Answer-True
Why do you invert petri dishes? - Answer-Condensation
can form on the lid when in the incubator. By inverting, the
condensation does not drip down onto the agar and
potentially contaminate the bacterial culture
Define sterilization and disinfection. - Answer-Sterilization:
the removal and killing of all microbes from a surface
Disinfection: the removal and killing of some microbes
from a surface
What is the reason for doing a 3 way streak? - Answer-To
get a single, pure colony
After working with S. aureus, where do you dispose of
your gloves? - Answer-Biohazard bin
,2|Page
List two things that aseptic technique accomplishes -
Answer-facilitate the creation of pure microbial cultures
keep the microbes only in certain/specific places
Keep people outside the lab safe
Prevent contamination
Describe how to properly do a 3 way streak - Answer-Step
1: obtain and label TSA plate
Step 2: Sterilize loop, cool, pick up bacteria, make first
streak (keep streaks tight, want to use as much surface
area as possible)
Step 3: Rotate plate 90°, sterilize loop, cool, and pull 1-2
pulls from end of S1 and make S2
Step 4: Rotate plate 90°, sterilize loop, cool, and pull 1-2
pulls from end of S2 and make S3
What is TSA? - Answer-Tryptic soy agar (TSA): artificial
growth medium that provides adequate nutrient and
growth conditions for microbes
, 3|Page
Name 2 of the 5 characteristics we use to describe
nutrient agar plates. - Answer-o Size
o Pigmentation
o Form
o Margin
o Elevation
(True/False): Microbes don't self-segregate into uniform
populations. - Answer-True
Macroorganisms carry with them a panoply of natural
______ - Answer-Microflora
Name the three types of symbiotic relationships and briefly
define each - Answer-o Mutualistic-both benefit neither are
harmed
o Commensal- one benefits and the other neither benefits
or is harmed
o Parasitic-one benefits and one is harmed
