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Microbiology | Questions & Answers
| Grade A | 100% Correct - Portage
Learning
Question:
Why is culturing anaerobic bacteria challenging?
Answer:
They cannot grow in oxygen-rich environments.
Question:
How is oxygen removed from media for culturing anaerobes?
Answer:
Using reducing agents like thioglycolate or anaerobic chambers.
,Question:
What is used inside an anaerobic chamber to remove oxygen?
Answer:
Oxygen-reactive chemical packets
Question:
What types of specimens may contain anaerobic bacteria?
Answer:
Wounds, blood, reproductive/GI tracts, cerebrospinal fluid, and lungs
Question:
What must be done if the dilution streak does not yield individual colonies?
Answer:
The experiment must be repeated
,Question:
On a Friday afternoon, you were hurrying to finish your microbiology lab. You
had been prepping and pouring nutrient broth agar plates. In your hurry, you
left one out on the lab bench uncovered and didn't discover it until Monday. It
had multiple colonies growing on it. What can you assume about the
microbes?
Answer:
Colonies are aerobic bacteria
Question:
A presentation was given on the discovery of a new bacterium detected on an
implantable device, called a pacemaker. A lab found the bacteria by doing
DNA analysis. However, no one has been able to grow a pure culture of the
bacteria even though they have optimized growing conditions to the human
body like pH, oxygen concentration, temperature, salinity.
What are possible explanations as to why the bacterium has yet to be
cultured?
Answer:
-It is a fastidious microbe
-The molecular techniques may be able to detect lower concentrations of the
microbe but cell number is still too low to culture
-It may take the microbe longer to grow to be detected
-The microbe may be an intracellular parasite and needs a host cell in which
to grow
, Question:
What is a "fastidious" microbe?
Answer:
A fastidious microbe has very specific and complex nutritional requirements
that standard lab media cannot provide.
Question:
What is the standard method of sterilization in microbiology labs, hospitals,
and research facilities?
Answer:
Autoclaving
Question:
How does autoclaving work?
Answer:
By using steam under pressure to denature proteins and disrupt cell
membranes, effectively killing microorganisms.