MCB2010:MCB2010L FINAL
BROWARD COLLEGE QUESTIONS
AND ANSWERS.
urease test purpose - Answer rapid or slow urease production
urease test media - Answer phosphate buffer
phenol red
urea breaks down into - Answer ammonia and co2
urease test results - Answer positive: bright pink
weak positive: pale pink
negative: orange
The ammonia produced causes the broth in a urease media tube to become - Answer
alkaline and overcome a buffer added to the medium, resulting in a color change to bright pink
by the pH indicator phenol red.
nitrate test purpose - Answer to determine the ability of an organsim to breakdown Nitrate
(NO3) to Nitrite (NO2) and Nitrite (NO2) to ammonia (NH3), Nitric Oxide (NO) and Nitrous Oxide
(N2O).
nitrate test media - Answer nitrate reagent A & B only react with nitrite NO2 to turn red
(positive)
HCL AND ZINC
oxidize nitrate to nitrite
nitrate test results - Answer positive: red after reagents A & B nitrate reductase available
postive: clear with zinc both nitrate and nitrite reductase available
negative: red with zinc nitrate broken down by hcl and zinc
catalase test purpose - Answer presence of catalase
catalase test media - Answer hydrogen peroxide
, catalase test results - Answer positive: bubbles form hydrogen peroxide breaks down into
h2o and oxygen gas
negative: nothing happens
oxidase test purpose - Answer presence of Cytochrome C Oxidase to determine if the
organism is capable of aerobic cellular respiration.
oxidase test media - Answer filter paper
oxidase reagent
oxidase test results - Answer positive: bacteria is blue
negative: nothing
negative: blue ring
Dnase test purpose - Answer determine the ability of an organism to utilize nucleotides from
DNA or RNA as a nutrient source
Dnase test media - Answer dna media plate
HCL denatured DNA causing precipitation
Dnase test results - Answer positive: clearing
negative: no clearing
Dnase test clinically important for - Answer staph aureus
casease test - Answer used to detect the presence of the casease enzymes. breakdown milk
casein
casease media - Answer skim milk
nutrient broth
casease test results - Answer Positive: clearing
negative : nothing
starch test purpose - Answer determine starch hydrolysis
BROWARD COLLEGE QUESTIONS
AND ANSWERS.
urease test purpose - Answer rapid or slow urease production
urease test media - Answer phosphate buffer
phenol red
urea breaks down into - Answer ammonia and co2
urease test results - Answer positive: bright pink
weak positive: pale pink
negative: orange
The ammonia produced causes the broth in a urease media tube to become - Answer
alkaline and overcome a buffer added to the medium, resulting in a color change to bright pink
by the pH indicator phenol red.
nitrate test purpose - Answer to determine the ability of an organsim to breakdown Nitrate
(NO3) to Nitrite (NO2) and Nitrite (NO2) to ammonia (NH3), Nitric Oxide (NO) and Nitrous Oxide
(N2O).
nitrate test media - Answer nitrate reagent A & B only react with nitrite NO2 to turn red
(positive)
HCL AND ZINC
oxidize nitrate to nitrite
nitrate test results - Answer positive: red after reagents A & B nitrate reductase available
postive: clear with zinc both nitrate and nitrite reductase available
negative: red with zinc nitrate broken down by hcl and zinc
catalase test purpose - Answer presence of catalase
catalase test media - Answer hydrogen peroxide
, catalase test results - Answer positive: bubbles form hydrogen peroxide breaks down into
h2o and oxygen gas
negative: nothing happens
oxidase test purpose - Answer presence of Cytochrome C Oxidase to determine if the
organism is capable of aerobic cellular respiration.
oxidase test media - Answer filter paper
oxidase reagent
oxidase test results - Answer positive: bacteria is blue
negative: nothing
negative: blue ring
Dnase test purpose - Answer determine the ability of an organism to utilize nucleotides from
DNA or RNA as a nutrient source
Dnase test media - Answer dna media plate
HCL denatured DNA causing precipitation
Dnase test results - Answer positive: clearing
negative: no clearing
Dnase test clinically important for - Answer staph aureus
casease test - Answer used to detect the presence of the casease enzymes. breakdown milk
casein
casease media - Answer skim milk
nutrient broth
casease test results - Answer Positive: clearing
negative : nothing
starch test purpose - Answer determine starch hydrolysis
