Portage Microbiology BIOD171 Exam 5
Questions with 100% Verified Correct
Answers
Define the concept of universal precautions. - ✔✔Universal precautions
means any and all samples, whether known or unknown, are to be treated
as potentially hazardous (or pathogenic) materials.
List at least 3 observations a researcher would be sure to note while
assessing an unknown microbial sample. - ✔✔A lab researcher would be
certain to note:
Size and shape
Any observable motility
Gram status (positive or negative)
The presence of any chemical reactions
Changes in color localized to the organism or the surrounding media
Capture (or draw) images of any of the characteristics described above
, While observing an unknown sample of limited amounts, a researcher must
determine the following observations: (1) the presence of any motility and
(2) its Gram status using the same sample—the liquid sample cannot be
divided. Which would you determine first and why? - ✔✔You must
determine motility before determining the Gram status. Motility requires a
wet mount, while Gram staining requires heat fixing the sample. If one were
to begin with the Gram stain the heat fixation process would kill the
organism, making any observations regarding motility impossible. The
correct approach would be to place the liquid culture on a glass slide and
determine its motility status. Next, the same liquid culture can be heat fixed
and Gram stained.
A facultative anaerobe is a microorganism capable of growth under what
conditions? - ✔✔A facultative anaerobe is capable of growth under aerobic
(with oxygen) and anaerobic (without oxygen) conditions.
As Streptococcus is catalase negative would it thrive or die in the presence
of peroxides? Why? - ✔✔Streptococcus is catalse negative which means it
cannot break down peroxides and if any peroxides are present it would die.
Streptococcus is most often streaked onto: - ✔✔Blood agar
Questions with 100% Verified Correct
Answers
Define the concept of universal precautions. - ✔✔Universal precautions
means any and all samples, whether known or unknown, are to be treated
as potentially hazardous (or pathogenic) materials.
List at least 3 observations a researcher would be sure to note while
assessing an unknown microbial sample. - ✔✔A lab researcher would be
certain to note:
Size and shape
Any observable motility
Gram status (positive or negative)
The presence of any chemical reactions
Changes in color localized to the organism or the surrounding media
Capture (or draw) images of any of the characteristics described above
, While observing an unknown sample of limited amounts, a researcher must
determine the following observations: (1) the presence of any motility and
(2) its Gram status using the same sample—the liquid sample cannot be
divided. Which would you determine first and why? - ✔✔You must
determine motility before determining the Gram status. Motility requires a
wet mount, while Gram staining requires heat fixing the sample. If one were
to begin with the Gram stain the heat fixation process would kill the
organism, making any observations regarding motility impossible. The
correct approach would be to place the liquid culture on a glass slide and
determine its motility status. Next, the same liquid culture can be heat fixed
and Gram stained.
A facultative anaerobe is a microorganism capable of growth under what
conditions? - ✔✔A facultative anaerobe is capable of growth under aerobic
(with oxygen) and anaerobic (without oxygen) conditions.
As Streptococcus is catalase negative would it thrive or die in the presence
of peroxides? Why? - ✔✔Streptococcus is catalse negative which means it
cannot break down peroxides and if any peroxides are present it would die.
Streptococcus is most often streaked onto: - ✔✔Blood agar
