BIOSCI 221 EXAM QUESTIONS AND ANSWERS
LATEST UPDATE
Gelatin test
Measures/determines: Gelatinase
Medium: Nutrient gelatin
Results: (-) gels/solidifies, (+) liquefaction
Reference organism: Bacillus cereus
Citrate tests
Measures/determines: Organisms ability to use citrate as source of carbon
Medium: Simmon's citrate agar
Results: (-) remains green, (+) Prussian blue
Reference organism:
Sprorosarcina ureae (Q)
Gram + cocci, sarcina arrangement, spore former
Mycobacterium smegmatis (F)
Off-white, waxy appearance, gram +, pellicle with flocculent appearance in TSB
Bacillus cereus (S)
Gram +, thick spreading growth on TSA, brick-like morphology
Alcaligenes viscolactis (I)
Oxidase positive, spreading fuzzy growth pattern on TSA, growth in pH 10 both
Citrobacter Fruendii (K)
Slight metalic green sheen on EMB, positive Simmon's citrate, negative methyl red test
Lactococcos lactis (D)
Gram + cocci in short chains, aerobic, tiny colonies on TSA
Moroxella catarrhalis (N)
Gram -, diplococcus, white plastic appearance on TSA
Escherichia coli (W)
- Citrate test, + indole and methyl red tests, green sheen on EMB
Pseudomonas fluorescens (O)
Gram - rod, top growth on FTM, lime-yellow appearance on TSA
Staphylococcus epidermidis (R)
Grape-like clusters of small spheres, gram +, large halo present around Novobiocin disk
Clostridium sporogenes (B)
Gram + rod, spore former, bottom growth on FTM
Kinyoun staining procedure
Objective: Mycolic acid presence
Primary stain: Carbol-Fuchsin
Secondary stain: Methylene blue
Kligler's Iron slant medium (lactose fermentation, H2S+)
Yellow slant, yellow butt, black percipitate
Heat fixed slide of Corynebacterium pseudodiphtheriticum after Schaeffer-Fulton
stain
LATEST UPDATE
Gelatin test
Measures/determines: Gelatinase
Medium: Nutrient gelatin
Results: (-) gels/solidifies, (+) liquefaction
Reference organism: Bacillus cereus
Citrate tests
Measures/determines: Organisms ability to use citrate as source of carbon
Medium: Simmon's citrate agar
Results: (-) remains green, (+) Prussian blue
Reference organism:
Sprorosarcina ureae (Q)
Gram + cocci, sarcina arrangement, spore former
Mycobacterium smegmatis (F)
Off-white, waxy appearance, gram +, pellicle with flocculent appearance in TSB
Bacillus cereus (S)
Gram +, thick spreading growth on TSA, brick-like morphology
Alcaligenes viscolactis (I)
Oxidase positive, spreading fuzzy growth pattern on TSA, growth in pH 10 both
Citrobacter Fruendii (K)
Slight metalic green sheen on EMB, positive Simmon's citrate, negative methyl red test
Lactococcos lactis (D)
Gram + cocci in short chains, aerobic, tiny colonies on TSA
Moroxella catarrhalis (N)
Gram -, diplococcus, white plastic appearance on TSA
Escherichia coli (W)
- Citrate test, + indole and methyl red tests, green sheen on EMB
Pseudomonas fluorescens (O)
Gram - rod, top growth on FTM, lime-yellow appearance on TSA
Staphylococcus epidermidis (R)
Grape-like clusters of small spheres, gram +, large halo present around Novobiocin disk
Clostridium sporogenes (B)
Gram + rod, spore former, bottom growth on FTM
Kinyoun staining procedure
Objective: Mycolic acid presence
Primary stain: Carbol-Fuchsin
Secondary stain: Methylene blue
Kligler's Iron slant medium (lactose fermentation, H2S+)
Yellow slant, yellow butt, black percipitate
Heat fixed slide of Corynebacterium pseudodiphtheriticum after Schaeffer-Fulton
stain
