Question

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

Explanation:

Gram - staining is a common method in microbiology. Gram - positive bacteria retain the crystal violet - iodine complex (appearing purple) because of their thick peptidoglycan layer. Gram - negative bacteria lose the crystal violet - iodine complex during the decolorization step and take up the counter - stain (safranin, which is pink).

Answer:

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