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module 5 exam - bio171 microbio Questions
and Answers (Expert Solutions)
Q: The concept of treating all samples, whether known or unknown, as potentially
hazardous (or pathogenic) materials is known as _____.
ANS 🗹🗹: universal precautions
Q: List at least 3 observations a researchers would be sure to note while assessing an
unknown microbial sample.
ANS 🗹🗹: size and shape, motility, gram status, color change, chemical reactions
Q: While observing an unknown sample of limited amounts, a researcher must determine
motility and Gram status using the same sample. What would you determine first and
why?
ANS 🗹🗹: Motility because Gram staining requires the sample be fixed which would
kill the organism and then you can't observe motility
Q: a Facultative anaerobe is a microorganism capable of growth under what conditions?
ANS 🗹🗹: A microorganism capable of growth under aerobic and anaerobic
conditions
Q: as streptococcus is catalase negative would it thrive or die in the presence of peroxides?
Why?
ANS 🗹🗹: strep would not survive in the presence of peroxides b/c it is unable to
breakdown peroxides
Q: strep is most often streaked onto:
1.) chocolate agar
2.) EMB agar
3.) Blood agar
4.) Spirit blue agar
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ANS 🗹🗹: blood agar
Q: True or false: the Lancefield groups are used to subdivide antigenic groups of alpha-
hemolytic Steptococcus
ANS 🗹🗹: false
Q: The distinctions for Lancefield groupings lie in its
ANS 🗹🗹: Carbohydrate composition of antigens
Q: left untreated, strep throat can progress to___, which displays ___ hemolytic activity.
ANS 🗹🗹: Rheumatic fever ; beta
Q: Rheumatic fever displays (blank) hemolytic activity and occurs when (blank) is left
untreated
ANS 🗹🗹: Beta, strep
Q: True or false: under most circumstances, staphylococcus can be found in ~80% of the
human population where it remains non-symptomatic
ANS 🗹🗹: false
Q: Define commensal bacteria
ANS 🗹🗹: It neither harms nor benefits from the host from which it obtains
nutrients
Q: pathogen suppresses host immune system so it can continue replicating
ANS 🗹🗹: evasion
Q: pathogen passes through or between cells to access deeper tissues and nutrients
ANS 🗹🗹: infection
Q: pathogen is passed to another host to restart lifecycle
ANS 🗹🗹: transmission
module 5 exam - bio171 microbio Questions
and Answers (Expert Solutions)
Q: The concept of treating all samples, whether known or unknown, as potentially
hazardous (or pathogenic) materials is known as _____.
ANS 🗹🗹: universal precautions
Q: List at least 3 observations a researchers would be sure to note while assessing an
unknown microbial sample.
ANS 🗹🗹: size and shape, motility, gram status, color change, chemical reactions
Q: While observing an unknown sample of limited amounts, a researcher must determine
motility and Gram status using the same sample. What would you determine first and
why?
ANS 🗹🗹: Motility because Gram staining requires the sample be fixed which would
kill the organism and then you can't observe motility
Q: a Facultative anaerobe is a microorganism capable of growth under what conditions?
ANS 🗹🗹: A microorganism capable of growth under aerobic and anaerobic
conditions
Q: as streptococcus is catalase negative would it thrive or die in the presence of peroxides?
Why?
ANS 🗹🗹: strep would not survive in the presence of peroxides b/c it is unable to
breakdown peroxides
Q: strep is most often streaked onto:
1.) chocolate agar
2.) EMB agar
3.) Blood agar
4.) Spirit blue agar
, Page | 2
ANS 🗹🗹: blood agar
Q: True or false: the Lancefield groups are used to subdivide antigenic groups of alpha-
hemolytic Steptococcus
ANS 🗹🗹: false
Q: The distinctions for Lancefield groupings lie in its
ANS 🗹🗹: Carbohydrate composition of antigens
Q: left untreated, strep throat can progress to___, which displays ___ hemolytic activity.
ANS 🗹🗹: Rheumatic fever ; beta
Q: Rheumatic fever displays (blank) hemolytic activity and occurs when (blank) is left
untreated
ANS 🗹🗹: Beta, strep
Q: True or false: under most circumstances, staphylococcus can be found in ~80% of the
human population where it remains non-symptomatic
ANS 🗹🗹: false
Q: Define commensal bacteria
ANS 🗹🗹: It neither harms nor benefits from the host from which it obtains
nutrients
Q: pathogen suppresses host immune system so it can continue replicating
ANS 🗹🗹: evasion
Q: pathogen passes through or between cells to access deeper tissues and nutrients
ANS 🗹🗹: infection
Q: pathogen is passed to another host to restart lifecycle
ANS 🗹🗹: transmission
