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37 votes
37 votes
You have a mixture of gram positive and gram negative cells in culture. You prepare a slide from the culture and gram stain it, but when observing the sample using oil immersion, all cells appear purple. What is the likely technical reason why only purple-colored cells

User Andrei Shikalev
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1 Answer

22 votes
22 votes

Answer:

due to imperfections in the staining

Step-by-step explanation:
if you skip the decolorization phase and therefore not resorb the violet stain from the wall of the gram-negative bacteria, which will not provide a base for the obtaining of safranin stain which should stain the gram-negative bacteria red or pinkish, the gram-negative bacteria will have the same color as the gram-positive, so all the cells will be purple

User Josh Wilson
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