You are performing a Gram stain on gram-negative bacteria and you stop after the decolorizer step.What is the appearance of the bacteria at this point?
A)purple
B)red
C)colorless
D)brown

Question

Quizplus · Accepted Answer

After the gram-negative bacteria are treated with the decolorizer, the crystal violet-iodine complex is washed out from the bacteria's thick peptidoglycan layer. As a result, gram-negative bacteria will appear colorless and the gram-positive bacteria will be purple at this stage.

You Are Performing a Gram Stain on Gram-Negative Bacteria and You