Preview

Gram staining lab report

Good Essays
Open Document
Open Document
487 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Gram staining lab report
Gram Staining Lab
Introduction
Gram staining is a very important technique used in biology labs all over the world. It is a technique used to differentiate types of bacteria using certain physical and chemical characteristics of their cell walls. Gram positive bacteria (which show up purple after the gram staining process) have a very thick layer of peptidoglycan where gram negative bacteria (which show up pink after the gram staining process) have a much thinner layer of peptidoglycan. One thing to note is that not all bacteria are gram positive or gram negative, some are non-reactive to this type of staining. Bacteria that are non-responsive to this technique are known as gram insensitive.
I hypothesize that in the cultures used in this lab for gram staining will contain many gram negative and gram positive bacteria.
Material and Methods
The following things are needed to run a gram staining experiment:
1. Bacterial cultures
2. Glass slides
3. Cover slips
4. Ammonium Oxalate-Crystal Violet stain
5. Gram’s Iodine Solution
6. Ethyl Alcohol
7. Safranin Solution
8. Paper towels
9. Water
10. Bunsen Burner (Lighter will suffice)
11. Microscope 1. Prepare and heat-fix smears. 2. Stain the slides as follows: a. Flood the crystal violet for one minute. b. Pour off excess dye and wash gently in tap water and drain the slide against a paper towel. c. Expose the smears to Gram's iodine for one minute by washing with iodine, then adding more iodine and leaving it on the smear until the minute is over. d. Wash with tap water and drain carefully. (Do not blot.) e. Wash with 95% alcohol for 30 seconds. f. Wash with tap water at the end of the 30 seconds to stop the decolorization. Drain. g. Counterstain with 0.25% safranin for 30 seconds. h. Wash, drain, blot, and examine under oil. i. Draw the cells showing morphology, grouping, and relative sizes. Color a few of the cells of each

You May Also Find These Documents Helpful

  • Satisfactory Essays

    Lab Report On Unknown 32

    • 591 Words
    • 3 Pages

    The first test conducted on unknown bacteria 32 was the Gram stain. From this stain, unknown 32 was found to be a Gram-positive cocci. This test eliminated all possible Gram-negative bacteria, Gram-positive rods and Gram-positive spirillium. Next, the endospore test determined whether or not the Gram-positive bacteria contained endospores. With the use of malachite green, steam, and safranin it was found that unknown bacteria 32 did not contain endospores.…

    • 591 Words
    • 3 Pages
    Satisfactory Essays
  • Good Essays

    post lab of cucl2

    • 732 Words
    • 3 Pages

    14. Open the wet filter paper and lay flat on paper towel to dry overnight.…

    • 732 Words
    • 3 Pages
    Good Essays
  • Powerful Essays

    Double Unknown Lab Report

    • 1229 Words
    • 5 Pages

    The following tables are each corresponding to either the Gram-positive sample or Gram-negative sample and include the tests utilized along with their results all in the order each test was performed. In section 10, Figures, there are some pictures corresponding to the stains performed. In Figure 1, the Gram-positive stain, you can clearly see the purple color and cocci morphology in grapelike clusters. Figure 2 is the Gram-negative stain with the safranin color and shows bacilli cellular morphology.…

    • 1229 Words
    • 5 Pages
    Powerful Essays
  • Good Essays

    Gram staining is a technique that was invented by Hans Christian Gram in 1882 (Cantey & Doern, 2015). First, a drop of water was placed on a microscope slide. Using a loop and aseptic techniques (working by an open flame to prevent contamination, and sterilizing the loop in the flame until red hot), a small amount of bacteria from the master plate was mixed with the water then streaked onto the slide. The slide was allowed to dry, then the bacteria was heat fixed onto the slide by running it through the flame twice. A clothespin was attached to the slide and the slide was placed on a staining tray. The smear was covered with crystal violet and allowed to stain the bacteria for two minutes. Then, the slide was rinsed with distilled water at an angle, not directly onto the smear. Grams iodine was added to the slide and allowed to sit for one minute and rinsed again with distilled water. Next, the differentiation step occurred (Bartholomew & Mittwer, 1952) using a small amount of alcohol (about 8 drops) rinsed over the slide, followed immediately by rinsing with distilled water. Safranin was then added to the slide and allowed to sit for 30 seconds then rinsed with distilled water. After blotting the slide with bibulous paper, the slide was viewed under the microscope at 1000X magnification. The counterstain Safranin can be substituted for another…

    • 1550 Words
    • 7 Pages
    Good Essays
  • Better Essays

    Micro lab quiz 2

    • 1967 Words
    • 8 Pages

    The Gram stain separates bacteria into two major groups: Gram positives that stain purple, and Gram negatives that stain pink or red.…

    • 1967 Words
    • 8 Pages
    Better Essays
  • Good Essays

    10. Rinse the precipitate on the filter paper with more distilled water from the wash bottle to be…

    • 612 Words
    • 3 Pages
    Good Essays
  • Better Essays

    Unknown Lab Report

    • 2145 Words
    • 9 Pages

    The tests performed on the unknown bacteria cultures were all used to determine the identity of the bacteria. Each of the tests performed provided some key information about the bacteria in question and how it functions. Not all of the tests were performed on every culture, however, as some of the tests were used only for gram (+) or gram (–) bacteria, while others were even more specific and used only for cocci bacteria. The tests performed and what constitutes a positive and negative test are as follows.…

    • 2145 Words
    • 9 Pages
    Better Essays
  • Good Essays

    Gram Staining Lab

    • 423 Words
    • 2 Pages

    Prokaryotes are a large group of organisms with no membrane bound organelles. They consist of two domains: Archaea and Bacteria. These organisms are only found in extreme environments such as volcanoes. Prokaryotes are still being researched and are a very diverse group. In this lab we focused on trying to identify if the bacteria found had a lot of peptidoglycan by gram staining. Testing this could be done by using a Petri dish full of agar and testing different bacteria on it to see if the bacteria obtained is gram positive or gram negative. My hypothesis is there will be a lot of bacterial growth on all of the plate.…

    • 423 Words
    • 2 Pages
    Good Essays
  • Good Essays

    Unknown Lab Report

    • 1149 Words
    • 5 Pages

    Prepare two slides for gram staining and viewing under a microscope. {Either my gram-stain slides were bad or the microscopes I chose for viewing were not good. No bacteria were found under the microscope.}…

    • 1149 Words
    • 5 Pages
    Good Essays
  • Good Essays

    Unknown Bacteria Report

    • 586 Words
    • 3 Pages

    Gram staining showed gram negative rods, a motility test was also conducted to see if the bacterium moved or not, it was found to be none motile. Three different types of agar plates were used, they had two known bacterium put on along with the unknown to be able to compare negative and positive results if the known with the results of the unknown, refer to Barbaro (2016) for how the test were done.…

    • 586 Words
    • 3 Pages
    Good Essays
  • Good Essays

    Moldy Bread Project Paper

    • 594 Words
    • 3 Pages

    5. Take a small piece of paper towel and run it under tap water just enough to make it damp. Squeeze out any excess…

    • 594 Words
    • 3 Pages
    Good Essays
  • Good Essays

    Unknown Bacteria Essay

    • 614 Words
    • 3 Pages

    Secondly both bacteria had to be gram stained, so that they could be identified as gram-positive or as gram-negative. The same gram staining method was used for both bacteria, which consisted of inoculating each bacteria into a…

    • 614 Words
    • 3 Pages
    Good Essays
  • Good Essays

    Demo Speech Tie Dye

    • 604 Words
    • 3 Pages

    B. You must prep the dye before you get started! Please , at this time put on your gloves!…

    • 604 Words
    • 3 Pages
    Good Essays
  • Better Essays

    Plasmolysis is the process in plant cells in which the cytoplasm is separated from the cell wall as a result of water loss through osmosis.…

    • 743 Words
    • 6 Pages
    Better Essays
  • Good Essays

    The Mung Bean Production

    • 873 Words
    • 4 Pages

    Set anywhere - in low light and at room temperature (70° is optimal) between Rinses.…

    • 873 Words
    • 4 Pages
    Good Essays