BIOL 402 Exam 3 || A+ Guaranteed.
The tests that we use in this class for differentiation of species directly examine: correct answers
phenotype (expressed biochemical activities)
Which of the following could potentially cause a false species identification when using a
dichotomous key? correct answers - genetic changes previously occurred
- the test specimen/culture contained multiple species
- improper dichotomous key used
- a test result was misread
What type of material is agar? correct answers carbohydrates
Which type of test utilizes latex beads decorated with immunoglobin molecules that "recognize"
and bind a specific shape? correct answers Agglutination
What is the selective agent in Mannitol Salt Agar (MSA)? correct answers sodium chloride
If you were concerned that ;your hemolysis assay was not working properly, what could you
perform as a positive control? correct answers Add streptolysins (purified enzymes) to test media
What does the relatively heavy growth on the plates covered by the mask and lid during exposure
tell you about UV radiation? correct answers As lethal as UV is to the cells, it can't penetrate the
plastic or the cardboard
Would removal of sodium chloride from MSA alter the medium's sensitivity or specificity?
correct answers specificity
Would a false positive from the reaction between the inoculating loop and hydrogen peroxide be
caused by poor sensitivity or specificity of the test system? correct answers Poor specificity
Why can't your test substance [the potential mutagen] contain protein? correct answers Bacteria
could obtain histidine from the test substance
Which plate(s) do you need to examine to determine if your test substance is mutagenic? correct
answers The minimal media plate (MM)
A positive DNA hydrolysis test does not distinguish between Staphylococcus DNase and the
DNase produced by Serratia. If you had the expertise to correct this weakness in the system,
would you be improving the test's sensitivity or specificity? correct answers You would improve
its specificity - it would them be able to discriminate between the two types of DNase
Why does the LB/amp/ara/+DNA plate fluoresce when the LB/amp/+DNA plate does not?
correct answers The GFP is only expressed in the presence of arabinose
The tests that we use in this class for differentiation of species directly examine: correct answers
phenotype (expressed biochemical activities)
Which of the following could potentially cause a false species identification when using a
dichotomous key? correct answers - genetic changes previously occurred
- the test specimen/culture contained multiple species
- improper dichotomous key used
- a test result was misread
What type of material is agar? correct answers carbohydrates
Which type of test utilizes latex beads decorated with immunoglobin molecules that "recognize"
and bind a specific shape? correct answers Agglutination
What is the selective agent in Mannitol Salt Agar (MSA)? correct answers sodium chloride
If you were concerned that ;your hemolysis assay was not working properly, what could you
perform as a positive control? correct answers Add streptolysins (purified enzymes) to test media
What does the relatively heavy growth on the plates covered by the mask and lid during exposure
tell you about UV radiation? correct answers As lethal as UV is to the cells, it can't penetrate the
plastic or the cardboard
Would removal of sodium chloride from MSA alter the medium's sensitivity or specificity?
correct answers specificity
Would a false positive from the reaction between the inoculating loop and hydrogen peroxide be
caused by poor sensitivity or specificity of the test system? correct answers Poor specificity
Why can't your test substance [the potential mutagen] contain protein? correct answers Bacteria
could obtain histidine from the test substance
Which plate(s) do you need to examine to determine if your test substance is mutagenic? correct
answers The minimal media plate (MM)
A positive DNA hydrolysis test does not distinguish between Staphylococcus DNase and the
DNase produced by Serratia. If you had the expertise to correct this weakness in the system,
would you be improving the test's sensitivity or specificity? correct answers You would improve
its specificity - it would them be able to discriminate between the two types of DNase
Why does the LB/amp/ara/+DNA plate fluoresce when the LB/amp/+DNA plate does not?
correct answers The GFP is only expressed in the presence of arabinose
