Gram Staining Lab Report

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Introduction

In this lab report I use two different techniques to identify Unknown A and Unknown B bacteria’s. These techniques are gram staining and metabolic testing. I first used Gram staining to distinguished and identify the bacteria’s. Han Christian discovered gram staining in 1882, he had biopsy a patient lung that had pneumonia. The main purpose for Gram staining is to identify if is Gram positive or Gram negative by using differential staining. While Gram staining shows the difference between Gram Positive and Gram negative and its size, shape and morphology. This techniques as it limits. For example, I was doing Gram staining and I noticed that I had more then one gram- negative with rod shapes and gram -positive with coccus shapes. This make it very difficult to tell which ones were my unknown A and unknown B so, I needed to do further testing. This testing is called metabolic testing. Since bacteria’s have different genetic makeup and produce different types of enzyme that are unique in the way they help with biochemical reaction. Metabolic testing is testing how a particular
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Then I rinse with water over the staining dish. Secondly, I will add Gram iodine (Mordant) for another minute, which then the cells will the form a crystal a complex with crystal violet then rinse off the stain. The third step is to add 95% ethanol 5-10 second if the bacteria are Gram negative it would the cell would look colorless for the and if it is Gram positive the color would remain purple. I did then rinse the 95% ethanol off with out water not too much. Because the water stop bacteria from decolonization and you want to be able to see the bacteria under the microscope. The last agent you would add was safranin and this is too put back the color to the bacteria. I would then rinse and blot dry on bibulous paper. Then put oil on the slide then observed under the microscope-using eyepiece

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