Common Microorganisms Essay

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Microorganisms such as bacteria, fungus, mold, and yeast are present and common in almost every environment on earth. The normally microscopic organisms can easily be seen using differing types of agar, which creates an ideal environment for the organisms to form colonies, which are groups of hundreds of organisms that can be seen with the naked eye. In order to see individual microorganisms, it is necessary to use the magnification of a high-powered microscope.
These techniques of microbiology are used in the following five experiments. The first experiment used Trypticase Soy Nutrient Agar (TSA), which can grow a wide variety of organisms and contains casein and soybean meal and a minute NaCl, to study the effectiveness of
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Label them A, B, C, and D.
3) Press the pad of a dirty thumb onto quadrant A.
4) Swab the thumb with sterile water, allow to dry, and imprint it onto quadrant B. The sterile water acts as a control.
5) Press the other dirty thumb onto quadrant C.
6) Swab this thumb with the alcohol swab, allow to dry, and imprint on quadrant D.
Experiment 2. Effectiveness of mouthwash as an antiseptic
1) Divide a petri plate with Trypticase soy agar into 2 quadrants.
2) Swab the inside of your mouth with a sterile cotton swab, inoculate one half of the agar.
3) Rinse your mouth with Listerine brand mouthwash. Wait 5 minutes after rinsing.
4) Swab the inside of your mouth with a clean sterile swab, inoculate the second half of the agar.
Experiment 3. Normal human flora
1) Obtain two petri dishes containing one half Trypticase Soy Agar and one half Mannitol Salt Agar.
2) Moisten two sterile swabs in sterile water, remove excess water, and then use one of them to swab the inside of your nose, and the other to swab a patch of skin, like your neck.
3) Inoculate each dish of agar with either the nose or shin swab on both sections.

Note: For experiments one through three, each petri plate should be taped shut and stored upside-down for one week at room temperature to incubate the
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