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MICROBIOLOGY LAB FINAL EXAM VERSION 1 ACTUAL
EXAM 2025/2026 NEWEST ACTUAL EXAM WITH COMPLETE
QUESTIONS AND VERIFIED ANSWERS |ALREADY GRADED
A+|
By convention, plate counts from liquid cultures are always
reported in scientific notation accurate to:
Question options:
A)
One decimal place.
B)
Two decimal places.
C)
As many decimal places as are shown on the calculator. -
ANSWER-One decimal place.
To get just the right amount of water on your slide to make a nice
smear for microscopy it is best to:
Question options:
A)
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Hold your loop under a dripping tap, and 'catch' a loopful of water
that can then be placed on the microscope slide.
B)
Pour a small amount of water from a water blank (the kind you
used for the serial dilution last lab) into the center of the
microscope slide.
C)
Hold the slide under the tap, and then very carefully turn the tap
on until a single drop lands on your slide. - ANSWER-Hold your
loop under a dripping tap, and 'catch' a loopful of water that can
then be placed on the microscope slide.
To make a smear for microscopy from a sample growing on a
Petri plate, I should:
Question options:
A)
Pick a single colony, by scooping the entire colony up with my
loop, and then mix the entire loopful into a drop of water on the
slide until the mixture is thick and cloudy. Heat the slide gently
over the flame of the burner to both dry the slide and heat fix it, at
the same time.
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B)
Touch several colonies with my needle and then smear them
across a dry microscope slide. Add a drop of water and then heat
fix over the pilot flame of the burner.
C)
Touch a single colony with my needle, and mix it into a small drop
of water on my microscope slide. Let it air dry and then heat fix it
over the pilot flame of the burner. - ANSWER-Touch a single
colony with my needle, and mix it into a small drop of water on my
microscope slide. Let it air dry and then heat fix it over the pilot
flame of the burner.
When Gram staining, you will be reaching across your workstation
to use the staining sink in the middle of the bench. When you're
reaching across your work station, it is best to:
Question options:
A)
Have the Bunsen burner turned on with the hot blue flame, and
close at hand, in case you need to sterilize something while you
are Gram staining.
B)
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Have the Bunsen burner turned off entirely. If you need it again
after your Gram stain is finished, you can always re-light it later.
C)
Have the Bunsen burner turned on with a pilot flame, and pushed
off to the side of your work station, so you can use it again as
soon as your Gram stain is finished. - ANSWER-Have the Bunsen
burner turned off entirely. If you need it again after your Gram
stain is finished, you can always re-light it later.
When rinsing the stain from a slide, I should:
Question options:
A)
Turn the tap on as strong as it will go, and rinse the smear with a
direct stream of water to remove every bit of stain.
B)
Turn the tap on so that it has a gentle stream of water, let the
stream hit the end of the slide and run over the surface to rinse
the smear.
C)
MICROBIOLOGY LAB FINAL EXAM VERSION 1 ACTUAL
EXAM 2025/2026 NEWEST ACTUAL EXAM WITH COMPLETE
QUESTIONS AND VERIFIED ANSWERS |ALREADY GRADED
A+|
By convention, plate counts from liquid cultures are always
reported in scientific notation accurate to:
Question options:
A)
One decimal place.
B)
Two decimal places.
C)
As many decimal places as are shown on the calculator. -
ANSWER-One decimal place.
To get just the right amount of water on your slide to make a nice
smear for microscopy it is best to:
Question options:
A)
, Page |2
Hold your loop under a dripping tap, and 'catch' a loopful of water
that can then be placed on the microscope slide.
B)
Pour a small amount of water from a water blank (the kind you
used for the serial dilution last lab) into the center of the
microscope slide.
C)
Hold the slide under the tap, and then very carefully turn the tap
on until a single drop lands on your slide. - ANSWER-Hold your
loop under a dripping tap, and 'catch' a loopful of water that can
then be placed on the microscope slide.
To make a smear for microscopy from a sample growing on a
Petri plate, I should:
Question options:
A)
Pick a single colony, by scooping the entire colony up with my
loop, and then mix the entire loopful into a drop of water on the
slide until the mixture is thick and cloudy. Heat the slide gently
over the flame of the burner to both dry the slide and heat fix it, at
the same time.
, Page |3
B)
Touch several colonies with my needle and then smear them
across a dry microscope slide. Add a drop of water and then heat
fix over the pilot flame of the burner.
C)
Touch a single colony with my needle, and mix it into a small drop
of water on my microscope slide. Let it air dry and then heat fix it
over the pilot flame of the burner. - ANSWER-Touch a single
colony with my needle, and mix it into a small drop of water on my
microscope slide. Let it air dry and then heat fix it over the pilot
flame of the burner.
When Gram staining, you will be reaching across your workstation
to use the staining sink in the middle of the bench. When you're
reaching across your work station, it is best to:
Question options:
A)
Have the Bunsen burner turned on with the hot blue flame, and
close at hand, in case you need to sterilize something while you
are Gram staining.
B)
, Page |4
Have the Bunsen burner turned off entirely. If you need it again
after your Gram stain is finished, you can always re-light it later.
C)
Have the Bunsen burner turned on with a pilot flame, and pushed
off to the side of your work station, so you can use it again as
soon as your Gram stain is finished. - ANSWER-Have the Bunsen
burner turned off entirely. If you need it again after your Gram
stain is finished, you can always re-light it later.
When rinsing the stain from a slide, I should:
Question options:
A)
Turn the tap on as strong as it will go, and rinse the smear with a
direct stream of water to remove every bit of stain.
B)
Turn the tap on so that it has a gentle stream of water, let the
stream hit the end of the slide and run over the surface to rinse
the smear.
C)
