Why must young cultures be used when doing a Gram stain? What part of the bacterial cell is most involved with Gram staining, and why? What is the function of the iodine solution in the Gram stain? If it were omitted, how would staining results be affected? What is the purpose of the alcohol solution in the Gram stain? What counterstain is used? Why is it necessary? Could colors other than red be used?
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Young cultures must be used when doing a Gram stain because older cultures may have damaged cell walls, leading to inaccurate results. In older cultures, Gram-positive bacteria may appear as Gram-negative due to cell wall degradation. Show more…
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