The eighteenth exercise of the laboratory manual titled Unknown Identification and Bergey’s Manual is an experiment to identify an unknown bacterium. In this exercise, a student must randomly choose a numbered bacterium available to the class. The keys in Appendix H, located on the last pages of the book, are the major helpful tools in this exercise because it provides completed steps of tests that needs to be performed in order to distinguish certain bacteria. This means that in this exercise, various types of tests and techniques must be performed to identify the chosen unknown bacterium. The unknown bacterium that I selected was number thirty-nine in which I discovered as the Bacillus megaterium after conducting several tests. I began my test to classify my unknown bacteria by performing the Gram staining because according to the first period procedure of the laboratory manual and the Appending H, it was the first test that should be done to plan and proceed to the next tests. Washed bottle of distilled water, three slides, and Gram-staining reagents …show more content…
The bacterium’s colonies on trypticase soy agar had an irregular shape, yellow pigment, umbonate elevation, and entire margin. Through Gram staining, I microscopically examined that the bacterium was Gram positive, rod shaped, and arranged in chains. There was presence of bubbles after testing for catalase, therefore it was a catalase positive. The bacterium was an Endospore positive because after a close examination under a microscope, I observed that it had Subterminal endospore as the its position. The Acid from mannitol test resulted as positive because the phenol mannitol red broth became yellow orange. Finally, the V-P test was negative because the media turned yellow. Overall, these results means that the unknown bacteria were Bacillus
Each person has different characteristics about them that give them their own identity and that should not be changed. In the story “Harrison Bergeron” by Kurt Vonnegut, the main character, Harrison Bergeron is known as a threat to society. He is very intelligent, handsome, and athletic. In 2081, every person in the United States is equal. The government has taken over and has required everyone to wear handicaps to make them less smart, less pretty, less strong, and many other things. At the beginning of the story they mention a husband and wife, George and Hazel Bergeron, and they have a son, Harrison, who gets taken away because of his perfections. Later in the story, Hazel and George are watching ballerinas on television, when the program is interrupted by breaking news. They inform the viewers that Harrison has broken out of jail. The program then turns back on and Harrison appears on stage with the ballerinas. He proceeds to take off every
The isolate possesses some enzymes required for hydrolytic reactions. Hydrolytic enzymes found to be secreted from the bacterium, are -amylase, casein, and PYRase. In the starch hydrolysis and casein tests, there was a zone of clearing around the bacterium, which was indicative of the secreted enzymes necessary to break down starch and casein. In the PYR test, the presence of PYRase was detected by a color change to red on the PYR disc after the addition of the PYR reagent (p-dimethylaminocinnamaldehyde). Hydrolytic enzymes for which the EI tested negative were urease, gelatinase, and DNAse. In the Urea Hydrolysis test, it was observed that the urea broth did not have a color change, indicating that there was no urease secreted to break down urea in the broth. Similarly, there was no gelatinase present to break down gelatin in the Gelatin Hydrolysis test, so the nutrient gelatin remained solid. It was concluded that the EI does not possess DNase because there was no clearing zone around the bacteria, indicating that DNA had not been
After 5 days of growth each slant was tested using the gram staining technique to confirm the complete isolation of the bacteria. Both isolations were completely successful. Then each sample of bacteria was subjected to a series of tests for identification.
Streak plate technique was used to isolate pure culture for each bacteria (2). The Gram stain was used to determine Gram reaction and morphology of each bacteria (2) Selective and differential media such as, salt agar, MacConkey agar and blood agar were used for bacterial identification (2). Gelatin deeps were inoculated to detect production of gelatinase (2). Starch Agar plate were inoculated to detect amylase (2). Ocular reticle used to determine bacteria size (2). Motility deeps were inoculated to detect motility on bacteria (2). Thioglycollate broth used to determine oxygen requirements (2). Carbohydrate fermentation
The purpose of this study is to identify an unknown bacterium from a mixed culture, by conducting different biochemical tests. Bacteria are an integral part of our ecosystem. They can be found anywhere and identifying them becomes crucial to understanding their characteristics and their effects on other living things, especially humans. Biochemical testing helps us identify the microorganism present with great accuracy. The tests used in this experiment are rudimentary but are fundamental starting points for tests used in medical labs and helps students attain a better understanding of how tests are conducted in a real lab setting. The first step in this process is to use gram-staining technique to narrow down the unknown bacteria into one of the two big domains; gram-negative and gram-positive. Once the gram type is identified, biochemical tests are conducted to narrow down the specific bacterial species. These biochemical tests are process of elimination that relies on the bacteria’s ability to breakdown certain kinds of food sources, their respiratory abilities and other biochemical conditions found in nature.
Toni Marrison’s “Recitatif” describes his main characters, Twyla’s characteristic appearance on how Twyla seems to be happier on praising her mother’s beauty even she was abandoned. While in “Harrison” Bergeron by Kurt Vonnegut defines as his hero who desires to change an equal society in which everyone is equal to anyone including physical appearance, such as beauty. Thus, both authors argue differently on beauty. Making everything and everyone to appear gorgeous could help to build a better society.
Many people get sensible and feel miserable at the sight of cruel remarks on what they believe is sacred. Jon Krakauer wrote the book, Into the wild, to express his thoughts about his disapproval on what several people assume about Christopher McCandless, the main character. This people label McCandless stupid for leaving to Alaska without the vital equipment. To prove that he is not “stupid” for doing this he used appeal to pathos, appeal to logos and appeal to ethos.
The purpose of this laboratory is to learn about cultural, morphological, and biochemical characteristics that are used in identifying bacterial isolates. Besides identifying the unknown culture, students also gain an understanding of the process of identification and the techniques and theory behind the process. Experiments such as gram stain, negative stain, endospore and other important tests in identifying unknown bacteria are performed. Various chemical tests were done and the results were carefully determined to identify the unknown bacteria. First session of lab started of by the selection of an unknown bacterium then inoculations of 2 tryptic soy gar (TSA) slants, 1 nutrient broth (TSB), 1 nutrient gelatin deep, 1 motility
The Gram stain is a system used to characterize bacteria based on the structural characteristics of their cell walls. A Gram-positive cell will stain purple if cell walls are thick and a Gram-negative cell wall appears pink. Most bacteria can be classified as belonging to one of four groups (Gram-positive cocci, Gram-positive bacilli, Gram-negative cocci, and Gram-negative bacilli) (Phenotypic analysis. (n.d.).
Harrison Bergeron and 1984 were both based on a similar concept. This concept is creating peace by limiting and controlling the population. In George Orwell’s “1984';, it was done through brainwashing and doublethink. In Kurt Vonnegut’s “Harrison
The purpose of this project was to identify unknown bacteria species from a mixed culture. The two unknown species were initially plated onto Tryptic Soy Agar (TSA), Eosin Methylene Blue (EMB), Mannitol Salt Agar (MSA), and blood agar plates to distinguish between the two different bacteria using colony size, color, shape, and growth characteristics. By identifying and inoculating the differing types of colonies, the two unknown bacteria were purified and able to be tested
I identified the genus and species of an unknown bacterial culture, #16, and I applied the following knowledge of morphologic, cultural and metabolic characteristics of the unknown microorganism according to the laboratory manual as well as my class notes and power point print outs. I was given an incubated agar slant labeled #16 and a rack of different tests to either examine or perform myself; the tests are as follows: Gram Stain; Nutrient Gelatin Test; Carbohydrate Fermentation; Dextrose, Lactose and Sucrose; IMVIC tests; Citrate, Indole, Mythel-Red and Vogues Proskauer test; as well as a Urease and TSI Test. Materials and Methods/Results Upon receiving the Microorganism (M.O.) #16, I prepared a slide by cleaning and drying it. Then, using a bottle of water I placed a sterile drop of water on the slide and used an inoculating loop, flame sterilized, I took a small sample of the unknown growth in my agar slant and smeared it onto the slide in a dime sized circle and then heat fixed it for ten minutes.
In this method, living spores which are resistant to whichever sterilizing agent is being tested are prepared in either a self contained system, such as dry sp...
Leboffe, M. J., & Pierce, B. E. (2010). Microbiology: Laboratory Theory and Application, Third Edition 3rd Edition (3rd Ed.). Morton Publishing
The abnormal presence of bacterial growth can be inspected under a microscope. If the organism inspected is not the bacteria used in the experiment, it means that the growth of the bacterial culture investigated is absent. By using this method, contamination by foreign substances in the surrounding air can be ruled out and the results would be more accurate.