BSC 2011 LAB: Exam 2 | UPDATED Questions with 100%
Verified Answers
Q1: E. coli
A: in large intestines
Q2: microorganisms
A: can cause disease if they leave their normal habitat
Q3: rate of microbial spoilage
A: depends on chemical composition of affected substance(s) & types of organisms causing
infection
Q4: Agar
A: nutrient in patri dish
Q5: asceptic technique
A: prevents cross contamination
1) Flame inoculation loop & cool.
2) Transfer culture to slide with drop of H2O
3) Air dry slide.
4) Fix heat organism to slide. Pass slide through flame 3 times film side up. Let cool.
5) Crystal Violet. 1 minute. Rinse clear.
6) Lugol's Iodine (gram's iodine) MORDANT. 1 minute. Rinse clear.
7) Decolorize with ethanol. Rinse clear.
8) Safranin red. Counterstain. 1 minute. Rinse clear.
9) Blot dry.
Crystal Violet
Lugol's Iodine/ Mordant
Ethanol/Decolorize
Safranin red/ counterstain
Q6: mordant
A: substance makes cell more receptive to stain
Q7: flaming
A: sterilizes materials before & after use
Q8: Escherichia coli
A:
, Q9: Serratia marcescens
A:
Q10: Micrococcus luteus
A:
Q11: flagella
A: animal-like
Q12: Kingdom Prokaryotae
A: 2 domains
1) Archaebacteria
2) Eubacteria
Q13: peptidoglycan
A: Cell wall of prokaryotes, but NOT ARCHAEA. Made of a sugar polymer and polypeptide.
Verified Answers
Q1: E. coli
A: in large intestines
Q2: microorganisms
A: can cause disease if they leave their normal habitat
Q3: rate of microbial spoilage
A: depends on chemical composition of affected substance(s) & types of organisms causing
infection
Q4: Agar
A: nutrient in patri dish
Q5: asceptic technique
A: prevents cross contamination
1) Flame inoculation loop & cool.
2) Transfer culture to slide with drop of H2O
3) Air dry slide.
4) Fix heat organism to slide. Pass slide through flame 3 times film side up. Let cool.
5) Crystal Violet. 1 minute. Rinse clear.
6) Lugol's Iodine (gram's iodine) MORDANT. 1 minute. Rinse clear.
7) Decolorize with ethanol. Rinse clear.
8) Safranin red. Counterstain. 1 minute. Rinse clear.
9) Blot dry.
Crystal Violet
Lugol's Iodine/ Mordant
Ethanol/Decolorize
Safranin red/ counterstain
Q6: mordant
A: substance makes cell more receptive to stain
Q7: flaming
A: sterilizes materials before & after use
Q8: Escherichia coli
A:
, Q9: Serratia marcescens
A:
Q10: Micrococcus luteus
A:
Q11: flagella
A: animal-like
Q12: Kingdom Prokaryotae
A: 2 domains
1) Archaebacteria
2) Eubacteria
Q13: peptidoglycan
A: Cell wall of prokaryotes, but NOT ARCHAEA. Made of a sugar polymer and polypeptide.