MCB 2010C Final Lab Exam
`What is leukocytosis? - ANS-A higher than normal white blood cell count
How are results reported from TSI media? - ANS-slant (pH)/butt (pH)/gas/H2S
How does leprosy survive once inside of the body? - ANS-Chemically suppresses the
immune system
How is leprosy diagnosed? - ANS-On characteristics of disease, gram and acid-fast
staining, and biopsies from lesions and nasal secretions.
How is Tuberculosis diagnosed? - ANS-The procedures include acid-fast staining,
tuberculin skin tests, lumbar puncture, sputum, biopsy, body fluid culture, or polymerase
chain reaction.
How many coliforms will be in potable water? - ANS-1/100 mL sample
If a bactercult turns orange, what does this mean? - ANS-The organism did nothing.
Includes Group II organisms- Klebsiella, Staphylococcus, amd Streptococcus.
If a bactercult turns pink, what does this mean? - ANS-The organism breaks down urea,
and created alkaline conditions. Includes Group III organisms- Proteus and
Pseudomonas.
If a bactercult turns yellow, what does this mean? - ANS-That the organism fermented
lactose and acidified the media. Includes group I organisms- E. coli and Enterococcus.
If a bacterium does alter the color of MAC media, what does this mean? - ANS-The
bacterium is gram negative, lactose fermenting, lowers the pH of the media (acidic) and
changes the media from pink to red.
If an indole is produced on SIM media, what happens to the media? - ANS-A red film
develops on the top of the media.
If an organism contains urease, what color does it change to in urea broth? What color if
it does not? - ANS-If it contains urease, broth changes to a magenta. If it does not
contain urease, broth changes orange/yellow indicating an acidic pH.
, If an organism grows beyond the stab line on SIM media, what does this mean? -
ANS-That the organism is motile.
If the bacterium changes to a purple color on EMB agar, what does that mean? -
ANS-The bacterium is gram negative, and ferments lactose.
If the bacterium changes to a yellow color, what does this mean? pink? - ANS-If the
media turns yellow, this indicates glucose fermentation, and an acidic pH. If the media
turns pink, this indicates peptone from NH3 production, raising the pH alkaline.
If there is a coliform in the water put on an m-Endo plate, what will it look like? -
ANS-Will produce a metallic green sheath from the production of acetylaldehyde and
lactose fermentation.
What antigen is used in the Weils-Felix test? - ANS-Proteus
What are Alcaligines faecalis IMViC results? - ANS-Indole -, MR+, VP-, citrate-
What are Alcaligines faecalis results on TSI media? - ANS-K/K/-/-
What are Enterobacter aerogenes IMViC results? - ANS-Indole -, MR+, VP+, citrate+
What are Enterobacter aerogenes results on TSI media? - ANS-A/A/+/-
What are Escherichia coli IMViC results? - ANS-Indole +, MR+, VP-, citrate -
What are Escherichia coli results on TSI media? - ANS-K/K/+/-
What are Proteus vulgaris IMViC results? - ANS-Indole +,MR+, VP-, citrate-
What are Proteus vulgaris results on TSI media? - ANS-A/A/-/+
What are some general characteristics of fungi? - ANS-Absorptive heterotrophs (secrete
exoenzymes and absorb digested nutrients), cell walls made of chitin, decompose
organic matter, some are parasites. Divided into unicellular and filamentous. Individual
filaments are hyphae, groups of hyphae are called mycelium.
What are some general characteristics of Mycobacteria? - ANS-acid-fast, weakly gram
negative, can be cultivated except for M. leprae (because it is an intracellular pathogen)