BIOL 2051 Lab Midterm Exam LSU
Questions And 100% Correct Answers.
If you want to grow large volumes of a microbe, what type of media would be best to use? -
Answer broth
True or false: Some culture media, like MSA (mannitol salt agar), can be both selective and
differential. - Answer TRUE
Which of the following events immediately follows heating to dissolve media powder in water
when making plate media?
Allow media to temper
Allow agar to solidify
Pour plates
Autoclave flask of media - Answer autoclave flask of media
Which of the options below are sterilization techniques?
Filtration
Gas sterilization
Dry heat sterilization
UV radiation - Answer ALL
Allergies have been bothering you lately. As you were inoculating your streak plate with E. coli
you sneeze. With a plate in one hand and an inoculating loop in the other you were unable to
quickly cover your mouth. You tried to sneeze into your arm but your unstifled sneeze was
greater than your arm could shield. Following incubation of your plate, what do you expect to
see on the plate next lab?
Nothing because the media in the plate was sterilized.
There will be E. coli along with bacteria from your mouth on the plate.
Microorganisms are in the air transiently so there could be growth from contaminates in the air.
Nothing because you did not inoculate the plate. - Answer There will be E. coli along with
bacteria from your mouth on the plate.
Microorganisms are in the air transiently so there could be growth from contaminates in the air.
,True or false: The colony morphology of a microorganism is dependent on the medium on which
it is growing. - Answer TRUE
Which of the following term describes the optical properties of a colony?
shiny
opaque
dull
flat - Answer opaque
True or false: The colony morphology of a microorganism may differ if grown on different
medium. - Answer TRUE
Which of the following terms describes the whole colony shape of a colony?
umbonate
filamentous
round
lobate - Answer round
A doctor going into surgery vigorously washes his hands well and then suits up with gloves. Why
might he still need gloves even if he washed his hands really well, even with antibiotic soap?
Normal flora may be harmful when introduced into tissues or the bloodstream.
Washing hands do not rid them entirely of bacteria.
The patient has their own transient flora.
More of doctor's normal flora has been exposed. - Answer ALL
Normal flora may be harmful when introduced into tissues or the bloodstream.
Washing hands do not rid them entirely of bacteria.
The patient has their own transient flora.
More of doctor's normal flora has been exposed.
, True or false: You see more than one type of cell morphology when you stain cells from a single
colony on your streak plate. It is safe for you to consider that colony for obtaining a pure
culture. - Answer FALSE
True or false: After performing a simple stain on your mixed broth culture, you will view with
the microscope under 10x, then 100x with oil. - Answer TRUE
Which of the following statements is true?
Complex media is used for routine culturing because it is easier to make.
If an extract from yeast, plant, or animal is used in the media then it is complex.
Every molecule is known in defined media. - Answer ALL
Complex media is used for routine culturing because it is easier to make.
If an extract from yeast, plant, or animal is used in the media then it is complex.
Every molecule is known in defined media.
Why is aseptic technique necessary for the successful cultivation of pure cultures in the
laboratory?
To prevent contamination of your cultures
To allow you to feel confident that if you use a pure culture for an experiment, the results
generated will be from only that microorganism
To prevent contamination of yourself and the bench area
Aseptic technique is not really necessary. - Answer To prevent contamination of your
cultures
To allow you to feel confident that if you use a pure culture for an experiment, the results
generated will be from only that microorganism
True or false: It is not necessary to sterilize the inoculation loop after it has been used to
transfer a bacterial culture. - Answer FALSE
Which of the following are reasons to perform a streak plate?
To obtain a mixed culture from a pure culture.
To obtain a pure culture from a mixed culture.
To directly look at cell morphology.
Questions And 100% Correct Answers.
If you want to grow large volumes of a microbe, what type of media would be best to use? -
Answer broth
True or false: Some culture media, like MSA (mannitol salt agar), can be both selective and
differential. - Answer TRUE
Which of the following events immediately follows heating to dissolve media powder in water
when making plate media?
Allow media to temper
Allow agar to solidify
Pour plates
Autoclave flask of media - Answer autoclave flask of media
Which of the options below are sterilization techniques?
Filtration
Gas sterilization
Dry heat sterilization
UV radiation - Answer ALL
Allergies have been bothering you lately. As you were inoculating your streak plate with E. coli
you sneeze. With a plate in one hand and an inoculating loop in the other you were unable to
quickly cover your mouth. You tried to sneeze into your arm but your unstifled sneeze was
greater than your arm could shield. Following incubation of your plate, what do you expect to
see on the plate next lab?
Nothing because the media in the plate was sterilized.
There will be E. coli along with bacteria from your mouth on the plate.
Microorganisms are in the air transiently so there could be growth from contaminates in the air.
Nothing because you did not inoculate the plate. - Answer There will be E. coli along with
bacteria from your mouth on the plate.
Microorganisms are in the air transiently so there could be growth from contaminates in the air.
,True or false: The colony morphology of a microorganism is dependent on the medium on which
it is growing. - Answer TRUE
Which of the following term describes the optical properties of a colony?
shiny
opaque
dull
flat - Answer opaque
True or false: The colony morphology of a microorganism may differ if grown on different
medium. - Answer TRUE
Which of the following terms describes the whole colony shape of a colony?
umbonate
filamentous
round
lobate - Answer round
A doctor going into surgery vigorously washes his hands well and then suits up with gloves. Why
might he still need gloves even if he washed his hands really well, even with antibiotic soap?
Normal flora may be harmful when introduced into tissues or the bloodstream.
Washing hands do not rid them entirely of bacteria.
The patient has their own transient flora.
More of doctor's normal flora has been exposed. - Answer ALL
Normal flora may be harmful when introduced into tissues or the bloodstream.
Washing hands do not rid them entirely of bacteria.
The patient has their own transient flora.
More of doctor's normal flora has been exposed.
, True or false: You see more than one type of cell morphology when you stain cells from a single
colony on your streak plate. It is safe for you to consider that colony for obtaining a pure
culture. - Answer FALSE
True or false: After performing a simple stain on your mixed broth culture, you will view with
the microscope under 10x, then 100x with oil. - Answer TRUE
Which of the following statements is true?
Complex media is used for routine culturing because it is easier to make.
If an extract from yeast, plant, or animal is used in the media then it is complex.
Every molecule is known in defined media. - Answer ALL
Complex media is used for routine culturing because it is easier to make.
If an extract from yeast, plant, or animal is used in the media then it is complex.
Every molecule is known in defined media.
Why is aseptic technique necessary for the successful cultivation of pure cultures in the
laboratory?
To prevent contamination of your cultures
To allow you to feel confident that if you use a pure culture for an experiment, the results
generated will be from only that microorganism
To prevent contamination of yourself and the bench area
Aseptic technique is not really necessary. - Answer To prevent contamination of your
cultures
To allow you to feel confident that if you use a pure culture for an experiment, the results
generated will be from only that microorganism
True or false: It is not necessary to sterilize the inoculation loop after it has been used to
transfer a bacterial culture. - Answer FALSE
Which of the following are reasons to perform a streak plate?
To obtain a mixed culture from a pure culture.
To obtain a pure culture from a mixed culture.
To directly look at cell morphology.
