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

Question

Quizplus · Accepted Answer

After the addition of the mordant (iodine), gram-negative bacteria will appear purple because the crystal violet-iodine complex is still present in the cells at this stage.

You Are Performing a Gram Stain on Gram- Negative Bacteria