MICROANATOMY

Detailed explanation-1: -Gram’s decolorizer, a mixture of ethyl alcohol and acetone, is then added. This is the differential step. Gram-positive bacteria retain the crystal violet-iodine complex while Gram-negative are decolorized.

Detailed explanation-2: -A Gram stain is colored purple. When the stain combines with bacteria in a sample, the bacteria will either stay purple or turn pink or red. If the bacteria stays purple, they are Gram-positive. If the bacteria turns pink or red, they are Gram-negative.

Detailed explanation-3: -Gram’s Iodine is allowed to sit for 30 seconds then the decolorizor, 95% ethanol is added. Ethanol acts as a solvent which causes the crystal violet-iodine complex to dissolve away and rinse out of the cell wall if the cells are gram negative.

Detailed explanation-4: -The basic principle of gram staining involves the ability of the bacterial cell wall to retain the crystal violet dye during solvent treatment. Gram-positive microorganisms have higher peptidoglycan content, whereas gram-negative organisms have higher lipid content.