Perfect Paragraph 10

Gram stains are a very basic yet useful technique in determining types of bacterial cells. Gram negative cells have a thin outer membrane that can be easily broken down and dissolved. Gram positive have have the opposite, they have a thick outer coating. Gram stains rely on these two defining traits. The procedure for Gram staining is straightforward. First bacterial cells are placed on a microscope slide. If the cells are being drawn from a liquid solution they can be easily spread on the slide, if the cells are being used from a solid colony water must first be applied to the slide. Once the slide dries it will get heated fixed by passing it through a flame two times. This process ensures that the cells stick to the slide during the stain. The first stain of the bacterial cells is with crystal violet, this will turn the cells a purple color. Once the crystal violet is washed away with water the crystal violet is adhered to the cell after Gram’s iodine is applied. The Gram’s iodine will also be washed away with water. Next, the cells will be treated with ethanol. The ethanol will wash away the outer lining of Gram negative cells but not Gram positive cells. The cells will then be stained with pink safranin. This will turn Gram negative cells pink but will not affect the purple color of Gram positive cells because purple is darker than pink.