In Gram Twort stain, which substance is used as the decolorizer?

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Multiple Choice

In Gram Twort stain, which substance is used as the decolorizer?

In Gram Twort stain, the decolorizer is acidified alcohol. Its job is to remove the crystal violet–iodine complex from cells that do not retain it after the preceding staining steps. The acid component helps disrupt the outer membrane and the dye–cell wall interactions, so cells with thinner peptidoglycan (the Gram-negative type) lose the dye and take up the counterstain, while cells with thick peptidoglycan (the Gram-positive type) retain the purple color. Water wouldn’t effectively remove the dye, plain alcohol lacks the acid strength to differentiate as needed, and ethanol alone isn’t the specific decolorizing agent used in this protocol.

In Gram Twort stain, the decolorizer is acidified alcohol. Its job is to remove the crystal violet–iodine complex from cells that do not retain it after the preceding staining steps. The acid component helps disrupt the outer membrane and the dye–cell wall interactions, so cells with thinner peptidoglycan (the Gram-negative type) lose the dye and take up the counterstain, while cells with thick peptidoglycan (the Gram-positive type) retain the purple color. Water wouldn’t effectively remove the dye, plain alcohol lacks the acid strength to differentiate as needed, and ethanol alone isn’t the specific decolorizing agent used in this protocol.

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