The Results section needs to be detailed and should explicitly refer back to your hypothesis and explain whether the experiment confirmed or disproved the hypothesis. It can be found in soil, water and fecal matter. To determine between the two, I did the methyl red test next. Under a microscope, if the gram stain is purple, the bacterium is gram positive, if the stain is red, it is gram negative. The Original color of simmons is green.
This activity includes the application of procedure , technique and skills related to what type of Agar to be use to grow culture, inoculating and sterilizing, reagents to apply, handling of samples away from contamination and the skills in gram staining , handling and use of microscope and the differentiate differential and selective test for gram-negative and gram-positive bacteria. Gram positive bacteria are those that are stained dark blue or violet by Gram staining. My sample number was 18. Organisms were then identified through the microscope using 50x and 100x magnification. If bacteria have the enzyme citrate-permease they can transport molecules that will be converted to pyruvate within the cell. It was first discovered in 1885 by pediatrician and bacteriologist, Theodor Escherich 2. And, a negative methyl red test removed B.
The result, which presented the color blue after 15 minutes. This was completed by taking an inoculating loop and spreading the unknown out on to a Nutrient Agar plate. Indication of gram + bacteria. A positive citrate test ruled out P. A positive result is a red color in the liquid, and a negative result would be a yellowish color. This article was co-authored by. Title: The Process of Determining the Unknown Bacteria 9 Rachel Judecki July 5, 2011 2.
So, never use sites like:. This narrowed down the unknown to 5 possible answers: Escherichia coli, Klebesiella pneumoniae, Enterobacter aerogenes, Proteus vulgaris, and Pseudomonas aeruginesa. Table 1 and Table 2 list all of the biochemical tests, purposes, reagents, observations and results. After being incubated, a reagent was added in order to test for indole production, as per procedures found in McDonald et al. The aim of this document is to provide a general guideline on writing a lab report.
Gram-staining was utilized as a first step to differentiate between gram-positive and gram-negative. The first step that should be taken very seriously is cook meat well, especially ground beef. In order to determine the morphology of the bacteria a gram-stain followed the T-streak. In performing the experiment, the measurements for Zinc Sulfate and Barium Iodide did not deviate from the standard to be measured by more than 0. Bacteria, Cellular respiration, Gram staining 1765 Words 7 Pages Introduction The purpose of this lab was to identify unknown bacteria cultures using various differential tests, and my unknown bacteria is 17.
Introduction The purpose to this lab was to isolate and identify two unknown bacteria from a mixed culture provided to us by our instructor. The Simmons citrate test was performed, no color change meaning negative result. The results are also displayed in a flowchart. Depending on the results of each test we could narrow down the different bacteria to determine what our unknown is. Any kind of air bubbles is an indication that there was gas production. Identify two of these four items. Gram-positive cocci shaped bacteria were identified using the microscope.
A streak plate method will be used to obtain a pure culture of a Gram positive coccus genus of bacteria. The vegetative cell gives rise to the endospore which is stimulated by the depletion of nutrients. Not only have that metals also had a distinct shiny look which is called metallic luster. McClure Fall Semester 2014 Unknown Report Introduction The definition of Microbiology is the branch of science that deals with microorganisms. Day 5 — November 5, 2013 Reviewed Gram Positive agar plates. This proves the inability of E.
Lab Manual for General Microbiology ed. Introduction My unknown organism 6 is Morganella morganii, which is a gram-negative bacillus rods commonly found in the environment and also in the intestinal tracts of humans, mammals, and reptiles as a normal flora. Since the unknown sample contains a Gram + and a Gram - , it is just proper to make a growth for the unknown in an agar plate. The first procedure that was done was the gram stain. After performing the Gram stain to determine that the unknown was a Gram negative rod, the organism was grown on slant for use in inoculating the rest of the biochemical tests. The streak plate that was originally done, showed a heavy green pigment, which is a main characteristic of Pseudomonas auruginosa.
The instructor asked that each student isolate the two unknown bacteria and then identify each. The mannitol test was used to show if a bacterium could ferment mannitol. After five drops of the methyl red reagent were added a red color began to form which was an immediate indication of a positive test. The unknown gram positive bacteria is. Hypothesis: I predict that at least one of the tubes will not change color because of the little concentration it has. After 48 hours, each plate was observed. Introduction- Asexual Propagation is the process of using plant materials such as the stems, leaves, and roots to multiply the number of plants.