Bacteria Classification by Gram Staining Essay

First, obtain a SpectroVis Plus device and connect with its corresponding LabQuest2 device. You need to calibrate by turning on the machine, allow the inner lamp to start heating up, and prepping a blank in the process. Obtain a dry cuvette, fill it with distilled water, and place into the SpectroVis plus device. Before doing so, be sure to wipe the outside of the cuvette with a Kimwipe to clean off any fingerprints that might be present. Fingerprints will skew with the calibration. Once the device notifies you that calibration is complete, click okay and prep for the next part of the lab.

The illuminating parts of a microscope enable us to see the detail of the subject placed under the microscope. The three main parts that enable us to do this are: the condenser which illuminates the object that is placed under the microscope, the objectives which forms the magnified image, and the eyepiece which enables us to see the magnified

In this experiment, an unknown bacterium was given to each individual student. The main purpose of this lab was to identify the given unknown bacteria going through a series of biochemical tests as one of the gram negative bacteria among six different Gram negative bacteria Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa and Salmonella typhimurium. At the very beginning, streaking method; T-streak technique was used to isolate the pure colonies. For the morphological identification of unknown bacteria, Gram Stain Method was done. Biochemical tests that were conducted for the experiment

1) Apply the stain to your first unknown slide and examine it under the microscope.

10 Use test print to determine best 2nd exposure (white light) time and process as usual.

c. The color from the candies dissolved into the water and disappeared from half of each of the candies.

The first result of importance was the result of the Gram stain. The observations of the unknown bacteria from the slant culture after Gram staining showed that the unknown bacteria were Gram negative bacilli (Image 1). After determining the unknown bacteria was Gram negative, an oxidase test was conducted on a sample from the slant culture. The cotton swap with the sample of bacteria did not change color when the oxidase reagent was applied, thus providing a negative result. With a negative oxidase test, further tests were conducted to determine various characteristics of the unknown bacteria. A MR-VP broth was inoculated with a sample from a slant culture of unknown bacteria. After incubation, the methyl red reagent was added to the broth, and the broth turned red, providing a positive result (Image 2). An EMB agar streak plate was inoculated with a sample from a slant culture of the unknown bacteria, and after incubation, growth was found on the plate, providing a positive result (Image 3). A Citrate agar slant was inoculated, and after incubation, growth was found on the media, providing a positive result (Image 4). A Urea agar slant was inoculated, and after incubation, the agar had changed from a peach color to a bright pink color, providing a positive result (Image 5). Using the flowchart (Figure 1) developed from the Table of Expected Results, the lab partners started at the oxidase test. Given the negative result of the oxidase test, the flowchart is

Today in medicine doctors are rapidly isolating and distinguishing the many pathogenic microbes encountered daily within the environment. Public health has been affected from the faster identification of microorganisms by delivering an accurate analysis to patients in order to receive treatment of the disease in a timely manner. Due to the growing understanding of these organisms more have been easier to indicate to improve water quality. Also more methods have been developed for better treatment options from fecal bacteria in public water systems. Scientist has developed such specific methods of identifying the unknown organism to tell if the contamination has come from either a human, bird, or mammal. (Achtman et al., 2008)

My lab partner and I were given the Unknown Bacteria number four. We preformed multiple tests on it to determine what bacteria it was and have been able to classify it as Proteus vulgaris. Some identifying characteristics of this bacteria are that it is rod-shaped, gram-negative, catalase positive, produces hydrogen sulfide, is nitrate reduction positive, indole positive, urea positive, and is motile. There are multiple reasons that my partner and I believe that unknown bacteria number four is Proteus vulgaris. The tests that we have conducted and the results we have collected have led us to believe or decision is correct.

Procedure: First, set up the microscope. Clean the ocular lenses and objectives with lens paper. Then pace the prepared e slide on the stage and make adjustments. Turn the rotating nosepiece until the 10x objective is above the ring of light coming through the slide. Move the slide using the X and Y stage knobs until the specimen is within the view. Adjust the focus by looking into the eyepiece and focusing the specimen with the coarse then fine focus knobs. Adjust diaphragm until there is sufficient light

Sample area vigorously on several planes, maintaining the negative pressure. Note: Sample may be only in barrel of needle not in syringe. If no specimen is seen in syringe it does not mean an adequate sample has not been obtained

In the world of microbiology it is vitally important to be able to discern the identities of microorganisms. Not only is it important in a lab setting but as well as in healthcare in general. Properly identify what strain of bacteria a person has will aid in the proper medicine and dose given. Throughout the semester we have learned about different types of bacteria and certain test that can clearly identify them. The purpose of this lab report is to identify a Gram-positive or Gram-negative bacterium. Using all the knowledge of procedures and lab techniques identify the unknown and discuss all the tests you performed.

Erik Wicks Mrs. Slattery Biology Lab Report #1: Using a Compound Microscope Section: 5 Objective: What is the proper way to use a compound microscope and prepare a wet-mount slide? Hypothesis: A compound microscope is being used properly when the light source, nosepiece lens, and eyepiece lens work together to bring a magnified image to one’s eye. A wet-mount is properly prepared when a drop of liquid containing the sample is placed between the slide and a thin glass coverslip.

An analyzer interacts with the light beam after the light beam interacts with the sample.

Introduction: Through the conduction of numerous experiments, the identity of two bacterial isolates was determined. The tested specimen was an unknown sample of a mixed culture of two different species of bacteria. The first step that was taken was obtaining a pure culture of each species of bacteria by isolating one species from the other. Once isolation was complete, the isolated cultures were tested using procedures that had been performed during previous lab sessions. A gram stain was performed on the two isolates. The isolate which had tested gram negative was then tested for the presence of cytochrome C and lactose fermentation. For the gram positive isolate, cell shape was determined and a catalase test was performed.