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The Test And Lab Report

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Through out the semester we had conducted various tests and labs, we will use the knowledge we attained from previous exercises to trace out an unknown organism as the purpose for this lab report. Following the random selection of organism number 51, I started out using the “Gram- Positive Cocci in clusters” flow chart which comes from the class lab manual. After performing a hand full of tests, I came to a conclusion that organism 51 that I had chosen was St. mitis. I noticed that this organism was streptococcus but had both an individual and a chain like arrangement. The noted streak plate colony growth was round in shape, slightly elevated, smooth in texture and translucent or partially transparent.

The initial test that I had performed was the Gram staining test. I conducted this test a total of three times for final results. The Gram staining test is performed to differentiate between the two major categories of bacteria: Gram positive and Gram negative. In other words, the procedure enables bacteria to retain color of the stains which is based on the physical and chemical properties of the cells wall. The basic four step process of gram staining are: Application of the primary Crystal Violet stain onto a bacterial culture that had initially been heat fixed. The positive CV ions interact with the negatively charged bacterial components and happen to stain the bacterial cells purple. After rinsing the slide off with a gentle pressure of water, addition of Iodine on

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