...Introduction Bacteria are microscopic unicellular prokaryotic organisms characterized by the lack of a membrane-bound nucleus and membrane-bound organelles. They are remarkably adaptable to diverse environmental conditions and are found in bodies of all living organisms and on all parts of the earth. The purpose of microbial biochemical tests is to identify the unique traits it yields and with that knowledge we can then categorize them in groups and specify them by scientific name. These experiments included the Triple-sugar iron agar (TSIA), Sulfur Indole Motility (SIM), Methyl Red (MR), Voges-Proskauer (VP), Citrate, Urease, Gelatin, and Oxidase Test. In order for these tests to produce reliable and credible results, the bacterium organism must be grown using strict and meticulous procedure to produce viable colonies of pure culture. Having pure culture is significant to ensure that a single type of bacteria is used for identification without contamination so tests can be run without complications or confusion. Once all these tests are performed, the unknown bacteria in this lab will be one of the following: Escherichia coli, Enterobacter aerogenes, Proteus mirabilis, Klebsiella pneumoniae, or Salmonella typhimurium. This report included the results and details to these experiments which are discussed further on. Abstract Gram negative bacteria Unknown #12 was run through an array of tests which produced positive and negative results. The results obtained from the various...
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...Unknown Bacteria Lab Report #21 In Microbiology Lab, we learn the scientific method of streaking, staining, microscopy, aseptic culture, and selective and differential tests. These tests will help me identify my Unknown Bacteria. The first procedure I did was the isolation streak of my unknown out on a Trypticase Soy Agar. The purpose of Trypticase Soy Agar is to provide enough nutrients of the microorganism to grow. After I finish my isolation streak, my plate were incubated and grown. Once I got my plate to look at my results and I realize I started my streaking pattern wrong. Because of the way I started my streaking pattern I wasn’t able to see my own results. However, I did my own research of how my plate should have look like if I had did my streaking right. With an educated guess of my unknown species, the results I found for the plate have colonies agar that are tan- pigment, convex, circular, and smooth. The cells are also motile rods. The colonies can be observed under Ultraviolet Light. The second procedure was to perform a Gram stain. The purpose of the Gram stained method is to differentiate between a Gram positive and Gram negative organisms and also learning about the cellular morphology and arrangements. I carefully prepare a slide smear on three slides and then started the Gram stain procedure. Once the procedure was done, all three of my slides had a pink stain which automatically figured that my unknown bacteria was Gram negative. Then I examine the finished...
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...Bio 15 – Microbiology Final Unknown Report Sheet Unknown # ___90___ Genus and species of unknown _______Escherichia coli_________ Gram reaction and morphology ____Gram Negative reaction/Translucent and Shiny___ Other stains performed and results: Results: Please list the test results for all tests that were performed on the unknown. For tests not performed, write ND. |Carbohydrates: |IMViC Tests: | |Glucose |AG |Indole |+ | |Lactose |+ |Methyl Red |+ | |Mannitol |AG |Voges Proskauer |_ | | | |Citrate |ND | | | |Additional Biochemical Tests: | |Oxidase |_ |Lysine decarboxylase |+ | |Catalase |ND |Ornithine decarboxylase |ND...
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...microorganisms. The proper identification of a microorganism is not only important in a microbiology lab but also in the medical, industrial, and pharmaceutical fields. In this lab report, lab techniques and procedures learned during this course were performed to assess each students’ practical knowledge in microbiology. 6In area of fields I mention earlier microbiology is very important to our vaccination and antibiotics we are using, understand that microorganism play a key role in maintaining life on earth, fixing gases and breaking down dead plant and animal matter into simpler substances that are used at the beginning of the food chain 6. Biotechnologists can also exploit the activities of microbes to benefit humans, such as in the production of medicines, enzymes and food. The goal of this lab report is 1) to demonstrate comprehension of the methods and lab techniques learned during the semester 2) to explain the tests performed on each isolated unknown that led to the identification of each unknown 3) and to give a background on the characteristics, pathogenicity and some uses of one of the identified unknowns. II. Introduction In this lab report I will discuss how I came to find my two unknown bacteria. Each bacteria have undergo many different test to eventually identifying both bacteria. We understand that bacteria6 the discussion on the role of microbes in human welfare may be divided under two headings - good and bad 6. Microbes as we know are capable of both...
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...Unknown Laboratory Report Sarah Mansfield Biology 203 Professor Lana November 19, 2014 INTRODUCTION Microorganisms are the earliest forms of life and most have thrived since the early birth of the planet. They have evolved into many different forms of life such as animals, humans, and plants. While some microorganisms impact life in a positive way by sustaining life, others cause disease and even death (Nester, et al. 2012). Prokaryotes are one of the earliest organisms to exist, and many of these organisms can thrive in conditions far worse than other living things. For example, they can tolerate extreme temperatures, acidic, or alkaline environments (Foster 1996). Prokaryotic cells do...
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...ear Dr. Su: After your explanation of the unknowns lab report instructions, I am still left with a few questions concerning what should be the result for the lab the report. Therefore, I was hoping that you could explain to me what must be written in the report to receive a passing grade. My confusion to the assignment is in part due to the fact that my lab is inconclusive. In order to be able to classify the unknown as a certain bacteria I should be able to match its characteristics with different examples according to the different tests, but my sample matches none. I understand that in order to receive a good grade on the lab report the unknown must be correctly identified, therefore, creating more of a complication. During class you...
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...causing products they produce. Overall, microorganisms play an important role in life. The purpose of this study was to identify the unknown bacterium using biochemical tests and various methods that had been learned from previous the microbiology laboratory class. Identifying the unknown bacterium was determined by separating and differentiating possible bacteria based on specific biochemical characteristics. The differential tests used to identify the unknown cultures were Gram staining, oxidase, indole test, urea test, and casein test. MATERIALS AND METHODS: The unknown bacteria were given out by the lab instructor. Each student chose their own unknown bacteria according to the number. All methods have been practiced to ensure proper procedure identifying bacteria have been applied to this unknown. Procedures were followed as stated in the course laboratory manual provided by the instructor, unless otherwise noted. Each test performed identified was used to determine the specifics and identify the unknown bacterium. All of the following tests were performed on this unknown on February 09, 2008. Some of the tests required a follow-up right after the next lab. The first procedure that needed to be accomplished was to streak the unknown out on a Trypticase Soy Agar plate, using the T streak method described in the lab manual. The unknown culture was inoculated in the Tryptic Soy Broth tube, a TSA plate agar, and a TSA slant. This procedure is needed to be done in order...
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...Madeline M. Westrick Unknown 2 Unknown Lab Report INTRODUCTION In this study, each student was assigned a different unknown bacterium, with the task of identifying it correctly. Unknown 2 was Streptococcus pyogenes. S. pyogenes is gram-positive cocci that can result in human ailments that are classified as Streptococcal A infections, such as impetigo, cellulitis, erysipelas, and scarlet fever. The allotted testing time given was a total of four laboratory periods, or two weeks total. MATERIALS AND METHODS The unknown bacterial pathogen was presented via a liquid broth suspension in a double-walled glass test tube and on two nutrient agar (NA) plates. Its appearance was creamy yellow in color with sparse growth of medium-sized colonies...
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...IDENTIFICATION OF UNKNOWN BACTERIA It is virtually impossible to identify bacteria based on physical characteristics alone. This is due to the fact that there are only a few basic shapes and physical features commonly seen in the prokaryotic world. Instead, biochemical testing has been used to make bacterial identification down to the “species” level. These schemes are based on creating and matching biochemical profiles of the production of enzymes, acids and gases by isolated pure cultures of a given microorganism. Identification schemes and flow charts can be found in reference texts such as “Bergey’s Manual of Determinative Bacteriology” or “The Prokaryotes”. Each group of students will receive a TSA slant or broth containing a pure culture of an unknown bacterium belonging to the Family Enterobacteriaceae. It is the responsibility of the group to maintain stock cultures of the organism provided. Working stock cultures will be used to inoculate the various biochemical test media over the next several weeks and should be fresh and free from contaminants. A reserve stock culture should be made and after incubation and comparison with the original slant, kept with the original slant in the refrigerator. It is critically important that aseptic techniques are used during transfers and inoculations to prevent contamination of your cultures. If contamination is suspected, you will be able to fall back to your reserve stock. If you fail to maintain a reserve stock...
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...have certain bacteria that are considered good bacteria and therefore treating an infection with a selectively toxic agent would preserve the healthy bacteria in our body. B. Broad spectrum antibiotics are effective in inhibiting growth in a wide variety of both gram-positive and gram-negative bacteria. Such antibiotics are very important when time is limited in determining what kind of bacteria is causing a life-threatening infection. They are also beneficial when the exact bacteria that is causing the infection is unknown. Also, some infections are not just caused by one type of microorganism. However, there are certain types of bacteria that have developed resistance to broad spectrum antibiotics. Narrow-spectrum antibiotics are effective against killing just gram-positive or just gram-negative bacteria. They target the bacteria that is causing the infection while not killing as many or any of the normal bacteria. These antibiotics also cause less resistance to the bacteria. A disadvantage of narrow-spectrum antibiotics is that they can only be used to treat an infection in which the bacteria that has caused it is known. C. Certain enzymes may cause inactivation of antibiotics which causes resistance to antimicrobial agents. The bacteria’s target site may change in some way which reduces the effectiveness of antimicrobials. Certain bacteria are able to neutralize the agent and even prevent the agent from getting into the bacteria. Some bacteria may become...
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...HOW TO WRITE AN UNKNOWN LAB REPORT IN MICROBIOLOGY GENERAL Unknown reports in microbiology are written in scientific format. Scientific writing is written differently from other types of writing. The results of the exercise or experiment are what are being showcased, not the writing. The purpose of scientific writing is not to entertain, but to inform. The writing should be simple and easy to understand. There is a specific style that must be followed when writing scientific reports. Scientific writing is typically written in the passive voice. The pronouns "I", "We" and "They" are not typically used.. For example, instead of writing "I used a TSA agar plate to isolate my unknown," it is customary to write, "A trypticase soy agar (TSA) plate was used to isolate the unknown." It is also customary to write in the past tense for most of the report. This includes the introduction, the summary, the description of the materials and methods and the results. The present tense is reserved for the conclusions about the results. See the examples given below. Some other general rules that should be followed are: Microbial nomenclature: The name of the bacterium should written and spelled correctly. The name should be italicized or underlined. Italicized is preferred. For example, Staphylococcus aureus. The genus is capitalized but the species is not. After the full genus name is given in the paper, it can be written as S. aureus, but still italicized. This is as long as there in no other...
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...infections and from those eight, four have died. According to the lectures from class, we learned that nosocomial infections are infections that are transmitted from hospitals to patients through septic technique. The development of this infection was from a medical device that was used during an open-heart surgery. We also learned about Surgical Site Infections (SSI). According Central Disease Control and Prevention, CDC, this infections is basically is an infection that occurs in the body after surgery has taken place The Food and Drug Administration, F.D.A., have received thirty-two reports on patients who have been infected by this infection and the contamination of bacteria on these devices used during the open-heart surgery. From the 32 reports, there were 25 reports that were reported this year. From the reports that happened this year, eight of them happened in the United States. The rest of the reports were reported to have been contracted from Europe. As stated in the Microbiology textbook, the hospital environment has a large variety of pathogens laying around that are not known to the human. From lecture, five to fifteen percent of the hospital patients are mostly likely to attain the nosocomial infection. It also states that most of the microbes that are causing the nosocomial infections are not really infecting patients who are healthy, in fact the patients who have a weak immune system or have been through therapy are most likely to be impacted by the microbe. Some of the...
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...after the addition of the coagulase plasma in the brain infusion broth. Since S. epidermidis didn’t coagulate, this is indicating a negative result. S. epidermidis doesn’t have the free coagulase enzyme; therefore, no coagulation was present. In conclusion, not only did I prove my assumption correctly, but I was also able to find out the exact name for my organism. After the gram stain procedure I was able to assume that my organism was gram positive bacteria. The next step for me was to use the agars and broth that was specifically used for gram positive species. Among all the agars and broths used for gram positive bacteria, I used mannitol salt agar, blood agar, DNA agar, and brain heart infusion broth. If you look back at tables 1.2-1.5 you’ll see how the unknown reacted to these agars. Going back to the previous lab reports I compared and observed the results. With the knowledge I’ve retained I was able to connect the dots with the results and figure out that my unknown is Staphylococcus epidermidis and is a gram positive bacteria. ...
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...A critique of “Into the unknown” published by the economist (November 13, 2004.) Fear of losing jobs to offshoring (rise in unemployment), but computers and technology may take these jobs anyway. “Has the machines in its last furious manifestation begun to eliminate workers faster than new task can be found for them?” Article says not to worry. The United States has experienced an increase in the offshore outsourcing (offshoring) of jobs in the service industry. Although offshoring is common in the manufacturing industry, it only recently began in the service industry. The recent increase in the service industry has occurred because of new technology and the ability to access information from anywhere. Those who oppose offshoring believe it takes away American jobs, lower wages, and causes declines in America’s standard of living and any benefits from offshoring are unevenly distributed. Offshoring in the industry has not negatively affected the United States. Currently, offshore outsourcing in the service industry has a net benefit to society and there is no reason for concern. Critics charge that the information revolution (especially the Internet) has accelerated the decimation of U.S. manufacturing and facilitated the outsourcing of service sector jobs once considered safe, from backroom call centers to high level software programming. (This concern feeds into the suspicion that U.S. corporations are exploiting globalization to fatten profits at the expense of workers.)...
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... engineering, chemistry, geology, computer science, business, law, defense and education. Five early expert systems are detailed below. 1. DENDRAL DENDRAL is an expert system that examines the spectroscopic analysis of an unknown chemical compound and predicts its molecular structure. It was developed by Bruce Buchanan in the late 1960’s and its domain field is chemistry. It was designed to use mass spectrometry and other chemical information to deduce the molecular structure of chemical compounds. Its primary aim was to help organic chemists in identifying unknown organic molecules, by analyzing their mass spectra and using knowledge of chemistry. 2. MYCIN MYCIN is an early expert system that used artificial intelligence to identify bacteria causing severe infections, such as bacteremia and meningitis and to recommend antibiotics, with the dosage adjusted for patient's body weight. Its expertise lies in the domain of bacterial Infections. It was developed in MYCIN operated using a fairly simple inference engine, and a knowledge base of about 600 rules. It would query the physician running the program via a long series of simple yes/no or textual questions. At the end, it provided a list of possible culprit bacteria ranked from high to low based on the probability of each diagnosis, its confidence in each diagnosis' probability, the reasoning behind each diagnosis, that is, MYCIN would also list the questions and rules which led it to rank a diagnosis...
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