Gram staining

LAB REPORT NUMBER TWO DATE: 3/25/2010 inal attachment Lab Experiment number 11  PURPOSE: To learn the Gram stain technique, the reason for the stain, and how to identify the results of the organisms stained.  MATERIALS: Bunsen burner, inoculating loop, staining tray, glass slides, bibulous paper, lens paper, oil, and microscope  METHODS: Apply Crystal Violet (Primary stain) for 1 minute. Rinse with D-water Apply Iodine (Mordant) for 1 minute. Rinse with D-water. Apply Alcohol (Decolorize) for

processed through Gram staining test to determine the Gram stain and morphology. After Gram staining, a carbohydrate test was performed on each unknown to determine if it had glucose, sucrose, or lactose fermentation. The results of the sugar test help determining which biochemical test should be performed next. The Gram positive organism was tested through a carbohydrate fermentation test, then further tested to confirm its identity through an indole and catalase test. The Gram negative organism

that makes the cell gram negative. On the other hand, the characteristic that makes the cell gram positive is the thick peptidoglycan layer. 2. The peptidoglycan layer differs between a gram negative and gram positive cell. A gram negative cell has a thinner peptidoglycan layer, while a gram positive cell has a thicker peptidoglycan layer that results in a more 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

Under the microscope a rod shape pink cell was shown representing gram negative. This gram stain helps to determine the next test that would take place for further identification of the unknown organisms. The grain stain technique determined that unknown four was gram negative so the catalase test was further used where a small sample of the bacterium was added to a slide and a small drop of hydrogen peroxide was added

Christian Gram. Gram stumbled upon this method while he was examining some lung tissue from patients that had died of pneumonia. While examining 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

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

Lab Report A differential staining procedure used in microbiology is called the Gram stain. The significance of the Gram staining procedure is that it differentiates the bacteria into two groups. The Gram reaction of a bacterium adds valuable information for the treatment of disease. The Endospore stain is a special stain that is used to determine the presence of endospores in bacteria. This stain is used to detect if certain bacterium cell contain highly opposing spores within their vegetative

There are two types of staining: simple staining and differential staining. Staining is used to identify unknown bacterium including the structures within it and aseptic techniques should always be used. Bacterium is a transparent cell. Due to this, bacteria has to be stained and identified to be categorized. During simple staining, a sample of bacteria is taken from a culture. First, water is placed on a slide with a loop then, the bacteria is scratched onto the slide. It must dry completely before

discovered one of my bacteria was dead and had to acquire it separately from Dr. Christmann. Once my bacteria were separated, I began Gram staining. To Gram stain, I took a slide and spread each bacterium with a droplet of water onto two different slides. After heat-fixing, I stained with Crystal Violet for 1 min, rinsed with distilled water, stained with Gram Iodine for 1 minute, rinsed with distilled water, gently rinsed with 95% ethanol, rinsed with distilled water again, stained with Safranin

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