Lab Report: Microscope Bunsen Burner Beaker Test

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In this lab report a number of tests and results will be discussed. Unknown labs are performed for many reasons ranging from figuring out the causative agent in a diseased patient, to knowing the correct microorganism to use when making certain foods and antibiotics. Unknown labs are a key to testing the knowledge a student has gained throughout the course.
Materials:
Microscope Bunsen Burner Beaker Test Tube Holder Test Tube Clothes pin Striker Loops and Needles Distilled Water Crystal Violet Alcohol Safranin Iodine Methylene Blue Hydrogen Peroxide Reagent A (sulfanilic acid)
Reagent B (dimethyl-alpha-napthylamine) Kovacs Reagent EMb plate Blood plate MSA plate Starch plate Litmus milk tube Nutrient agar Slant
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The first procedure that needed to be done to identify the organism was a simple stain. Simple staining determines the micrograms morphology. The next procedure that had to be performed was a gram stain. Gram staining determines whether the microorganism is gram positive or gram negative. After doing these procedures it was determined that the organism was a gram positive cocci. The biochemical test performed were chosen based on this information.
Principles of biochemical test:
Test Reagents Purpose
Slant Shows Growth
Gelatin deep Shows Motility and production of
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After performing a gram stain to determine the organism was a gram positive cocci, a slant was inoculated for use in the rest of the biochemical test. The microorganisms being used in the class included only three gram positive cocci bacteria, Micrococcus luteus, Staphlococcus aureus, and Staphlococcus epidermidis. Upon realizing Micrococcus luteus tested negative for the voges-proskauer, lactose fermentation, and glucose fermentation tests it was automatically counted out. Staphlococcus epidermidis tested negative for both the voges-proskauer and lactose fermentation test. To further validate the conculsion of the unknown being Staphlococcus aureus, refer to the mannitol salt agar plate. The mannitol salt agar plate is selective for gram positive bacterium. Upon examining the plate it was realized that that the unknown organism grew a yellowish color and it produced acid, which resulted in a color change on the plate from red to yellow. In Bensons Microbiolobilogical Applications Labatory Manual, on page 362 it states that Staphlococcus aureus will appear yellow and it will produce acid to change the color of the plate, while the other two organisms will

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