Mycoplasma does not gram stain well due to which characteristic?

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Multiple Choice

Mycoplasma does not gram stain well due to which characteristic?

Gram staining relies on the cell wall’s peptidoglycan to trap the crystal violet-iodine complex and resist decolorization. Mycoplasma lack a cell wall entirely, having only a cytoplasmic membrane with sterols for stability. Without a peptidoglycan layer to retain the dye, the stain washes out during the decolorization step, so these organisms stain poorly or not at all. The other features listed—nuclei, mitochondria, and ribosomes—do not determine Gram reaction, and bacteria generally do not have nuclei or mitochondria. The absence of a cell wall is the reason Mycoplasma do not Gram stain well.

Gram staining relies on the cell wall’s peptidoglycan to trap the crystal violet-iodine complex and resist decolorization. Mycoplasma lack a cell wall entirely, having only a cytoplasmic membrane with sterols for stability. Without a peptidoglycan layer to retain the dye, the stain washes out during the decolorization step, so these organisms stain poorly or not at all. The other features listed—nuclei, mitochondria, and ribosomes—do not determine Gram reaction, and bacteria generally do not have nuclei or mitochondria. The absence of a cell wall is the reason Mycoplasma do not Gram stain well.

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