Unit 3--Lab Quizzes (7-9) Flashcards
Thermal Death Point
TDP: The lowest temperature that is required to kill a population of microbes when applied for a specific time
Where the first (-) is
Thermal Death Time
TDT: the amount of time that is necessary to kill a specific number of microbes at a specific temperature
Where the first (-) is
Why was Bacillus cereus resistant to heat killing?
Forms endospores
What percent of the original cells survive after 2 D-values of antimicrobial treatment?
1%
D-value: the number of minutes exposure to a defined temperature to reduce viable bacteria by 90%
100% viable
1 D value: 10% viable
2 D-value: 1% viable
What color did our fecal coliform colonies turn?
Blue
What compound makes mFC media differential?
Lactose
What color did our fecal streptococci colonies turn?
Red
What compound makes mEA media selective?
Azide
If you filter 10 mL of a 10-fold diluted water sample and find 20 colonies, how many cfu/100 mL were in the original sample?
2000 cfu/100 mL
(10 * 20 cfu)/10 mL
= 20 cfu/mL * 100
= 2000 cfu/100 mL
What term refers to cells that can take up naked DNA?
Competent
Virulent
Lysogenic
Diploid
Competent
Which of these scientists studied bacterial transformation?
Hershey and Chase
Watson and Crick
Griffith and Avery
Beadle and Tatum
Griffith and Avery
Why did we kill our resistant strain of bacteria?
To release endospores
To release DNA
To release proteins
To inactivate toxins
To release DNA
Which antibiotic resistance are we working with in our transformation demonstration?
Penicillin
Tetracycline
Polymyxin
Streptomycin
Streptomycin
Why do we add FeCl3 to wastewater in Big Rapids?
To remove excess oxygen
To remove excess phosphate
To remove excess nitrogen
To remove excess carbon
To remove excess phosphate
How is wastewater disinfected in Big Rapids?
Ozone
Chlorine
Heat
UV light
UV light
