Question

if we conduct the procedure correctly, what is the outcome of a well - executed gram stain?
a) gram - positive appear purple, and gram - negative appear pink
b) gram - positive appear pink, and gram - negative appear purple
c) both gram - positive and gram - negative appear purple
d) both gram - positive and gram - negative appear pink

Explanation:

In Gram staining, crystal violet is used as the primary stain. Gram - positive bacteria retain the crystal violet - iodine complex (due to their thick peptidoglycan layer) and appear purple. After decolorization, Gram - negative bacteria lose the primary stain and take up the counter - stain (safranin or fuchsine), which is pink.

Answer:

A. Gram - positive appear purple, and Gram - negative appear pink