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    Pandangan & Sardani - Activity-6-Isolation-Of-Microorganisms

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    Pandangan Matiyn
    The document compares the pour plate and streak plate methods of isolating bacteria. The streak plate reveals surface colonies while the pour plate reveals both surface and deep colonies. Surface colonies are aerobic whereas buried colonies are anaerobic. Agar is more rapid for proving purity of a culture through distinct colony morphology. Petri dishes are incubated inverted to prevent condensation and contamination from falling particles.

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    Pandangan & Sardani - Activity-6-Isolation-Of-Microorganisms

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    Pandangan Matiyn
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    The document compares the pour plate and streak plate methods of isolating bacteria. The streak plate reveals surface colonies while the pour plate reveals both surface and deep colonies. Surface colonies are aerobic whereas buried colonies are anaerobic. Agar is more rapid for proving purity of a culture through distinct colony morphology. Petri dishes are incubated inverted to prevent condensation and contamination from falling particles.

    Original Description:

    Microbiology Course_Isolation of Microbes

    Original Title

    PANDANGAN & SARDANI_ACTIVITY-6-ISOLATION-OF-MICROORGANISMS

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    The document compares the pour plate and streak plate methods of isolating bacteria. The streak plate reveals surface colonies while the pour plate reveals both surface and deep colonies. Surface colonies are aerobic whereas buried colonies are anaerobic. Agar is more rapid for proving purity of a culture through distinct colony morphology. Petri dishes are incubated inverted to prevent condensation and contamination from falling particles.

    Copyright:

    © All Rights Reserved
    Download as PDF, TXT or read online from Scribd
    Download as pdf or txt
    728 views2 pages

    Pandangan & Sardani - Activity-6-Isolation-Of-Microorganisms

    Uploaded by

    Pandangan Matiyn
    The document compares the pour plate and streak plate methods of isolating bacteria. The streak plate reveals surface colonies while the pour plate reveals both surface and deep colonies. Surface colonies are aerobic whereas buried colonies are anaerobic. Agar is more rapid for proving purity of a culture through distinct colony morphology. Petri dishes are incubated inverted to prevent condensation and contamination from falling particles.

    Copyright:

    © All Rights Reserved
    Download as PDF, TXT or read online from Scribd
    Download as pdf or txt
    of 2

    WORKSHEET

    Activity No. 6
    Name/s: PANDANGAN, Eissa Matiyn I. Date Performed: April 07, 2021
    SARDANI, Justine Lance B. Date Submitted: April 10, 2021

    Questions/Discussion:
    1. Compare the pour plate and streak plate methods of isolating bacteria?
    The key difference between a streak plate and a pour plate is that in a streak
    plate, the melted nutrient agar is added first, followed by a loop of bacteria from a
    slant, while in a pour plate, the bacterial broth is added first, followed by the nutrient
    agar.

    2. In which plate do you find the surface and the deep or buried colonies?
    The streak plate method reveals bacteria on the surface, while the pour plate
    method reveals bacteria deep within the nutrients. Streak plates are made from a
    loop of bacteria (from another plate or a liquid culture). To get isolated colonies,
    sterilize the loop in between streaks. Meanwhile, microaerobes, bacteria that can
    only withstand small quantities of oxygen, can be found in deep or buried colonies.
    Surface colonies would result from streak plating, while pour plating will result in
    both.

    3. How do surface colonies differ from deep or buried colonies?


    Surface colonies are aerobic, while buried colonies are mostly anaerobic bacteria.
    All of the bacterial colonies should be visible on the surface of your sample if you
    spread it out on an agar plate. The pollution you got when you poured the plates is
    what's deep in the agar. Just a few marine bacteria have been found to digest agar
    and create holes in it. Surface colonies would be exposed to air, while deep buried
    colonies would be in an anaerobic environment. Furthermore, surface colonies may
    lack sufficient nutrients, causing them to trigger the death process.

    4. Which is rapid in proving the purity of a culture – on an agar or in a broth?


    Since microbes have distinct colonies, agar is the medium rapid in proving the
    purity of a culture. To demonstrate purity, you must have a single type of colony and
    some single colonies on an agar plate. Colonial morphology (size, shape, color, and
    so on) must be consistent across all colonies. Broth rapidly grows bacteria, but a wet
    mount cannot be used to determine purity. Under a microscope, one rod may appear
    to be very identical to another.
    5. Why are petri dishes incubated in an inverted position?

    Agar plate is used in the laboratory for the development of microorganisms. The
    plates are frequently stored in the refrigerator, which can condense the lid. Where
    possible to prevent water falling on the agar surface, agar plates should be kept
    inverted. Additionally, petri dishes must be incubated upside-down to reduce
    contamination risks from airborne particles landing on them and to prevent water
    condensation from accumulating, which could disrupt or compromise a culture.

    VI. Conclusion:
    Most of the currently known bacteria species were identified using conventional
    methods such as gram stain reaction, morphology and metabolic reactions. The first
    step in identifying the bacteria that are likely to cause a disease process is to isolate
    one bacterium species. In this experiment, we successfully demonstrated the standard
    methods of obtaining a pure culture, even virtually. We were also able to appreciate the
    importance of pure cultures in the context of microbiology. Finally, we are able to
    determine the features of bacterial growth in our medium.

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