Gram Staining

Only available on StudyMode
  • Download(s) : 348
  • Published : November 17, 2010
Open Document
Text Preview
Gram Staining
Introduction
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. Materials and Methods

-Petri dish containing nutrient agar
-Cotton swabs
-Sharpie
A Petri plate containing nutrient agar was used in the experiment. A sharpie was used to section off four quadrants of the dish for the different bacteria. Cotton swabs were used to sample different areas of the building. Cotton swabs used by me and my lab partner were used to test areas from the hallway water fountain, vending machine, hallway floor, and the door handle to enter the classroom. Once done with this process, the cotton swabs were swiped on the four different quadrants of the Petri plate, covered and sealed, and set aside for a week to let the bacteria grow on the agar. Results

Once the week passed, the Petri dishes were full of growing bacteria. In quadrant A, the door handle, there was not much bacterial growth. In quadrant B, the water fountain, there was more bacterial growth than quadrant A and about one fourth of this quadrant had growth. In quadrant C, the vending machine, half of this quadrant was full of growth. In quadrant D, the hallway floor, almost the entire quadrant was full of bacterial growth with mold growing on the sides of the quadrant. Conclusion

The hypothesis I stated earlier was correct. Most of the quadrants obtained a lot of bacterial growth. Bacteria are found on places where people have...
tracking img