Identification of Micro-Organisms Term Paper Example | Topics and Well Written Essays - 3000 words

Identification of Micro-Organisms - Term Paper Example As micro-organisms have a colorless natural state when viewed through a light microscope, the organisms must be stained in order to be visible. Staining imparts a color to the micro-organisms’ by the reaction of the dye with certain structures of the microorganism (Tortora, 2006, p69) A simple stain is alcohol or aqueous based solution of a singular basic dye and its main purpose is to highlight an entire micro-organism in order for its cellular shapes and basic structure to be observed under a microscope (Tortora, 2006, p69). In this experiment, methyl blue was used as the simple stain to view microbes obtained from cheek and tooth-scraping. The illustrations on page 3 under the heading ‘Scientific Drawing 2’ shows the images that were observed. Figures 1.5 at x400 magnification and 1.6 at x1000 are scientific drawings of the eukaryotic epithelium cells obtained from a human cheek. When viewed at x1000 magnification most of the internal structures of the cells got from the cheek could be seen under a light microscope. Figures 2.3 and 2.4 are scientific drawings of prokaryotic bacterial cells obtained from human teeth scrapings. The bacterial cells, which are approx 1Â µm in diameter, are much smaller in comparison to the human cheek cell and hence the internal structures could not be observed even at x1000 magnification. Unlike simple stains, differential stains react differently with each bacteria and therefore can be used to differentiate between each type of bacteria (Tortora, 2006, p69) The most commonly used differential stains are Gram stain and Acid fast stains and the staining procedures involve several steps. In this experiment, Gram stain was used to distinguish between gram positive and gram negative bacteria, taken from a vaginal and a urine specimen. Figures 3.1and 3.2 are scientific drawings of gram positive and gram negative bacteria respectively as viewed under a light microscope at x1000 magnification.