The bacteria that are stained by the Gram stain technique are referred to as gram positive

The bacteria that are stained by the Gram stain technique are referred to as gram positive

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Gram Positive vs. Gram negative The bacteria that are stained by the Gram stain technique are referred to as gram positive . Bacteria that that are not stained by crystal violet are referred to as gram negative . The technique is based on the ability of a bacterium to retain the crystal violet dye during solvent treatment. If the crystal violet stain is retained it shows the difference cell wall and cell membranes. Gram negative bacteria have a thick lipid bilayer in comparison to gram-positive cells. Initially both kinds of bacteria will be stained by the crystal violet dye. Iodine is added to make the dye adhere strongly to the bacteria. This is called fixing the dye. Alcohol is added as a solvent to remove the dye. It removes the lipid bilayer from the gram-negative cells. By removing that layer, it makes it easier to remove the dye. Gram positive bacteria on the other hand will close pores in the cell wall making it nearly impossible for the dye to diffuse out of the cell.
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10) Pass the mouth of the test tube thru flame once more and close it. 11) Gently mix the bacteria on the wire loop in the drop of water on the glass
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The bacteria that are stained by the Gram stain technique are referred to as gram positive

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