In a Gram stain study, the bacteria that retains the blue coloration following staining, alcohol rinse, and restaining is:

Question

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Gram positive bacteria have a thick peptidoglycan layer in their cell wall which retains the blue coloration of the crystal violet stain used in the Gram staining process. This coloration persists even after the alcohol rinse and restaining with the counterstain safranin. Gram negative bacteria have a thinner peptidoglycan layer and an outer membrane that is dissolved by the alcohol rinse, causing the crystal violet stain to be lost and the bacteria to become red when restaining with safranin.

In a Gram Stain Study, the Bacteria That Retains the Blue