Bacterial Morphology Demonica Britt Microbiology DL1 March 23, 2013 Abstract This lab was performed to identify and familiarize with a microscope while precisely observing various bacterial shapes and their arrangements in different types of specimens of bacteria. The microscope parts and capabilities were clearly identified and used successfully and the bacteria were clearly illustrated showing the bacterial shapes and arrangements with all the appropriate magnification being utilized.
Through various magnifications using 10x, 40x and 100x oil immersion lenses, the bacteria specimens, along with fresh and prepared yogurt, demonstrated full visual optical views of their shapes and how the different types were displayed at different levels of magnification. Purpose The purpose of the experiment was to gain full knowledge and experience of operating a microscope while being able to successfully visualize different types of bacterial and yogurt specimen’s shapes and arrangements using several magnification techniques by way of 10x, 40x,100x oil immersion lenses and a light source.
The main purpose was to observe the shapes and arrangements of microbial bacteria and yogurt. Procedure The lab involved self-provided and labpaq materials to perform several exercises to obtain the purpose of the lab. The lab began with the proper identification of all components of the microscope and their functions. This allowed for preparation of the objective of being able to view specimens at various magnification levels and recognizing their different shapes and how they are arranged contingent upon those identified within the lab itself and the microbiology textbook.
Several different slides were observed under 10x and 40x lens magnification: Paramecium conjugation, Yeast, Amoeba Proteus, Ascaris eggs, Anabaena, and Penicillium. This allowed vivid illustrations of the specimens notating their shapes and how they are arranged. The bacteria were observed through the eyepiece at the appropriate focus, resolution, and contrast for maximum visibility. The next part of the lab exercise was observance under an 100x oil immersion lens for more prepared slides: Bacteria Coccus form, Bacteria spirillum, and Bacteria Bacillus form while still maintaining to observe the shapes and arrangements.
Additionally, the fresh yogurt slide that was sitting for 24 hours in a dark, warm location was obtained for the next part of the lab experiment. The fresh yogurt slide was prepared by using a toothpick to place a small amount onto a fresh, clean slide with a slide cover placed on top. This was observed for comparison to the prepared yogurt slide included in the lab for any variations in forms. Upon completion of performing the lab, the prepared slides were safely put away, fresh slide washed carefully, fresh yogurt specimen safely discarded, and the microscope cleaned and returned to be stored with the protective cover.
Data/Observations – (Data Tables & Photos of Labeled Pics & Observations) The bacteria slides clearly displayed the various types of bacteria shapes and showed how each follow a specified arrangement. Under the lowest magnification the object is relatively smaller and not as easy to see the full format. Whereas the higher the magnification, the bigger and more enhanced the view of the bacteria becomes making the shapes and arrangements relatively obvious. It appeared to become clearer the bigger the object projected to my eye.
It became life size in a sense where as it was an image that could be clearly defined, described and duplicated if necessary. The fresh yogurt slide that was set for 24 hours was a more enhanced feature for observing bacteria in yogurt. Its view was very detailed and its shape more recognizable. While the prepared yogurt slide was a more faint view and the color appearing duller. It was visible to me that bacteria in yogurt was more spherical in shape, cocci. Results A. What are the advantages of using bleach as a disinfectant? The disadvantages? The advantages of using 70% alcohol?
The disadvantages? Bleach is a common household disinfectant that kills 99. 9 percent of germs whereas others cannot approach this effectiveness. It can be used to sanitize. It can be a disadvantage as it can be inactivated by presence of an organic matter and it has a strong odor and it has a short life in the liquid form that can be sensitive to heat and sunlight. The advantages of using 70% bleach is that it can be capable of killing most bacteria which is safe for skin contact and it prevents dehydration and the alcohol part of it affect the cells in various ways.
Some disadvantages are that they are hazardous which contain compounds that are not safe and toxic to human form. B. List three reasons why you might choose to stain a particular slide rather than view it as a wet mount. C. Define the following terms: Chromophore: Acidic Dye: Basic Dye: D. What is the difference between direct and indirect staining? E. What is heat fixing? F. Why is it necessary to ensure that your specimens are completely air dried prior to heat fixing? G.
Describe what you observed in your plaque smear wet mount, direct stained slide, and indirectly stained slide. What were the similarities? What were the differences? H. Describe what you observed in your cheek smear wet mount, direct stained slide, and indirectly stained slide. What were the similarities? What were the differences? I. Describe what you observed in your yeast wet mount, direct stained slide, and indirectly stained slide. What were the similarities? What were the differences? J. Were the cell types the same in all three specimen sets: yeast, laque, and cheek? How were they similar? How were they different? Conclusion/Discussion Upon performing and completing the experiment I learned that the microscope is a very delicate tool that allows the capability of viewing specimens too small for the human eye. With adjusting the focus, contrast, and resolution, the bacteria become more visible to the eye. On top of that, viewing the specifications at different magnifications the bacteria shapes and arrangements become more present within the specimen.
Bacteria comes in different forms and shapes and just by arrangement alone, they can be classified morphologically. It was also visual that there are differences in a fresh slide containing bacteria compared with a slide already prepared. I did not expect to see the differences so vividly displayed, but after using the microscope it was determined that anything not visible to the naked eye still has the capability to be seen and the microscope is the perfect tool to use to be able to do so.