Staining

For this particular assignment, I was given a slant with an unknown bacteria by my lab instructor. There were several procedures performed to identify the unknown bacteria. The first procedure was streaking tryptic soy agar plate (TSY). The purpose of streaking is to identify the bacteria in a sample presenting a pure culture of colony morphologies. After several hours of incubating the streaked plate, visual isolated colonies were present. The steps to streaking are as follows; Flaming an inoculation

this lung tissue Gram discovered that certain stains were more favorable and retained by the bacterial cells. It was only a few years later that Gram produced a staining procedure that he divided into two groups. The two groups divided almost all bacteria into what he called Gram positive (purple) and Gram negative (pink). The Gram’s staining procedure is still used today and is the method that forms the basis for identifying bacteria. In order to perform this procedure, you will need a Bunsen Burner

complex NAM and NAG cross-linking. 3. Escherichia coli cells would be pink following a gram stain. E. coli is a gram negative cell due to its thin peptidoglycan layer and its outer membrane structure. In the gram staining process, the outer membrane does not play a role in staining but the peptidoglycan

The results that I observed by Gram Staining was Gram Negative rod (bacillus). Then, I performed a Negative Stain in order to further more validate that I had bacillus, since Negative Staining would provide an accurate determination of the shape of the microbe by staining the background of the microbe. In observation of my unknown using Negative Staining; I knew that I had a microbe with bacillus. Day#2: 　　I did a Fermentation Test where I inoculated

Acids in drinks factors in staining teeth. Tooth enamel contains microscopic pits that have the ability to hold particles of food and drinks. The dark color in tea, coffee, soda, and grape juice gives the yellow color on the teeth. Tannins are an ingredient in coffee and tea and more beverages. Tannins cause color compounds more readily stick to teeth. I used eggshells to replace actual teeth because eggshells and teeth are similar. Egg shells are made up of compounds of calcium carbonate. Tooth

Lab Report 3 Microscopy: Cell Structure and Gram Staining Part 1: Care and use of a Compound Light Microscope 1. The largest area can be viewed at 4x magnification. 2. The smallest area can be viewed at 100x magnification. Part 2: Differentiating bacteria with the Gram stain 1. Thick smears can lead to trapping the Gram Stain and lead to it being positive when it should be negative. Smears cannot be removed during decolonization. 2. The name given to E.coli was Bacilli because it is a rod- shaped

the organisms of two unknown bacterial cultures. Students must identify the species of the unknown bacteria by utilizing the techniques and information learned in previous laboratory exercises. These techniques include streaking for isolation, Gram staining, and specific biochemical tests. Students are given a map known as a dichotomous key, a guide in determining the identity of their unknown sample. Identifying microbes using a series of biochemical tests, like those performed by students, is used

a MacConkey agar plate. The first part of the experiment involved the methods of manipulating, identifying and counting the bacteria and the second part was to find out whether the bacteria E.coli was the only type found in the given area by gram staining. E.coli was the chosen bacteria for this type of experiment. It is a gram negative bacterium that will grow rapidly given ‘any culture medium with the necessary energy source, nutrients, pH, and temperature’. Therefore, MacConkey Agar being the

removed and it would become colorless. The last counterstain safranin was added to the slide a gram+ would remain purple and the gram – would turn pink or reddish in color. Meanwhile, after the gram staining, one were able to identify under the microscope that unknown bacteria

Plate B incubated at 25oC produced a white, opaque, waxy, and spreading bacteria colonies while plate A incubated at 37oC produced a white, thin spreading bacteria colonies (Figure 1.). Gram staining revealed that plate B contained a rod-shaped bacterium having partial pink and purple coloration with endospores. This suggests that the bacteria is a gram positive bacteria. Gram positive bacteria typically have a thick cell wall which traps the crystal violet making them appear purple. Conversely,