Lab Final

Card Set Information

Author:
mmorrow911
ID:
2173
Filename:
Lab Final
Updated:
2009-12-08 17:36:42
Tags:
MJC Micro Lab Final
Folders:

Description:
Lab Final Micro 101
Show Answers:

Home > Flashcards > Print Preview

The flashcards below were created by user mmorrow911 on FreezingBlue Flashcards. What would you like to do?


  1. Catalase Test

    • -The catalase enzyme breaks down the
    • peroxides into non-toxic H20 and 02. Enzyme is needed in order for a cell to
    • exist in the presence of o2

    • Reagent-hydrogen
    • peroxide

    • Positive Result- bubble formation after placing a drop of hydrogen
    • peroxide on colony

    Negative Result-no bubble formation
  2. Oxidase Test

    • -Cytochrome oxidase
    • is involved in the reduction of oxygen at the end of the ETC


    Reagent-Kovac’s

    • Positive result-purple color
    • change after oxidase reagent is added

    • Negative result-no color change
    • after oidase reagent is added
  3. O/F Carbohudrate Test

    • -Used to determine whether an organism derives energy from
    • sugars by fermentation or oxidation. Two
    • tubes are used; one tube is covered while the other is not. If the bacteria has the ability to only grow in the presence of O2 it will grow only in the O tube. If the bacteria has the ability to only grow in the presence of no O2 it will only grow in the F tube with fermentation. If the bacteria grows in both tubes it is facultative and will grow with or with out O2

    Left is (+) Middle indicates (+) with gas Right (-) test
  4. Methel Red

    • -Used to
    • identify bacteria that produce stable acid end products by means of mixed acid
    • fermentation of glucose

    • Positive result-red color
    • change indicating acid production

    • Negative result-no color
    • change
  5. Nitrate Reduction Test

    • -Test for
    • the ability to reduce nitrate into nitrite. If the organism can reduce the
    • nitrate, it will react with the reagent

    Reagents-Paba, Zinc

    • Positive result-nitrate(no30_____nitrite(NO2)-red
    • color change after addition of reagent

    • Negative result- nitrate(no30_____nitrite(NO2)-no
    • color change after addition of reagent
  6. Citrate Test

    Left (-) no color change Right(+) color change to blue

    • -Citrate
    • agar tests for the ability of organisms to utilize citrate as a sole carbon
    • source

    • Positive Result-blue color
    • change

    • Negative Result- no color
    • change
  7. Indole Test

    • -Checks
    • for the presence of tryptophanase, which breaks down tryptophan into indole,
    • ammonia & pyruvid acid

    Reagent-Kovac’s

    • Positive result-purple ring
    • at the top of the media

    • Negative result-brown or
    • yellow ring at the top of the media
  8. Urea Test

    • Straw
    • colored-uninnoculated Pink (+)
    • test Yellow-orange (-) test

    • -Checks
    • for the presence of the enzyme Urease that breaks down urea to form two
    • molecules of ammonia

    • Positive result- bright
    • pink color change

    • Negative result-light
    • orange to yellow color change
  9. H2S Test

    (-) no black (+) slight black (+) complete black

    • -Tests
    • the ability of an organism to produce hydrogen sulphide from thiosulphate

    • Positive Result-production
    • of black precipitate

    • Negative Result-no
    • production of black precipitate
  10. MSA (Manatol Salt Agar)

    • -Used for the isolation of Gram+ organisms. The high salt concentration of medium
    • inhibits the growth of most other organisms(selective). Some organisms ferment
    • the Mannitol into acid, this acid production turns the agar from red to
    • yellow(differential)

    • Positive Result-Growth of
    • bacteria with media change to yellow

    • Negative Result-Growth or
    • no growth of bacteria without media color change

    • (Bacteria unable to tolerate high
    • salt or unable to ferment mannitol)
  11. EMB (Eosin Methalane Blue Agar)

    • -Medium
    • used for isolation of Gram - rods. EMB inhibits the growth of Gram +
    • organisms(selective). Differentiates bacteria between lactose fermenting and
    • non-lactose fermenting organisms(differential)

    • 1) Growth on plate indiacates
    • organism is not inhibited(Gram – bacteria), green metallic sheen indicates
    • organism is able to ferment lactose, producing strong acid end products

    • 2) Growth on plate indiacates
    • organism is not inhibited(Gram – bacteria), absence of color in growth
    • indicates the organism is unable to ferment lactose

    • 3) Growth on plate indiacates
    • organism is not inhibited(Gram – bacteria), pink color indicates bacteria is
    • able to ferment lactose to produce weak acid end products

    • 4)No growth on plate indicates
    • organism is(Gram+)

    • Positive Result-Growth of
    • bacteria, colonies have dark centers and clear borders or metallic green sheen

    • Negative Result-Growth or
    • no growth of bacteria without media color change
  12. MAC (MacConkey Agar)

    • -medium
    • used for the isolation of (Gram- )organisms, it inhibits the growth of (Gram+)
    • organisms(selective). Differentiates bacteria between lactose fermenting and
    • non-lactose fermenting organisms(differential)

    • Positive Result-Growth of
    • bacteria, colonies have a pink appearance

    • Negative Result-Growth or
    • no growth of bacteria without media color change
  13. Mueller-Hinton Agar

    Standard growth medium used for antibiotic susceptibility testing
  14. Sheeps Blood Agar (SBA)

    Some microbes contain enzymes that can break open red blood cells (lyse host cells)

    α -(alpha) - partial/greenish appearance

    β - (beta) - complete cell lysis

    ϒ - (gamma) - No cell lysis
  15. pGLO
    • an engineered plasmid used as a vector for creating genetically modified organism
    • contains reporter genes
    • -green fluorescent protein
    • -ampicillin resistance gene/codes for exoenzyme(ampicillinase)
    • Arabinose(sugar)-makes the organism fluoresce under UV light
  16. Coliforms
    commonly used bacteria indicator of sanitary quality of food and H20 of the coli family
  17. Indicator Organism
    Used to masure potential fecal contamination of environmental samples (present in human waste in high enough numbers to be readily detected)
  18. Virulence factors
    Responsible for causing disease in the host as they inhibit curtian host functions
  19. Plasmids
    Small extra-chromosomal elements that can exist in some bacteria. The bacterial genome is made of bacterial chomosome and any plasmids that the organism may contain.

    Usualy carry the genes for antibiotic resistance
  20. High copy number
    Plasmids may have up to 300 copies of itself in any one bacterial cell it can produce up to 300 copies of gene product that it caries in that bacterial cell.
  21. Zone of Inhibition
    Circle around the disk where the antibiotic noticeably affected cell viability
  22. Antibiotics
    Chemicals that have the ability to kill bacteria

    Produced by microorganisms (fungi), used as a defense mechanism

    Derived from microoganisms or Synthetically produced
  23. Antiseptics
    Chemicals used on living tissue to kill microbes

    Mouthwash
  24. Disinfectants
    Chemicals used on the surface of inanimate objects to kill microbes

    Bleach
  25. Disk-diffusion method
    Used to determine the effectiveness of antibiotics on certain bacteria
  26. Multiple tube technique
    Is a method, to detect coliforms in two stages

    Presumptive test- test for acid and gas production

    Confirmed test - uses EMB agar

    # of coliforms in sample detemined by MPN method
    • 1. Obligate aerobe
    • 2. Obligate Anarobe
    • 3. Facultative anaerobic organism
    • 4. Microaerophile
    • 5. Aerotolerant
  27. Parts of a Microscope

What would you like to do?

Home > Flashcards > Print Preview