Prince George Community College » Biology » Bio 2010 - Microbiology » Summer 2021

Question #1

Which of the following is the Gram's primary stain?

A. Loeffler's methylene blue

B. Crystal violet

C. Safranin

D. Acetone- Alcohol

E. Carbolfuchsin

Question #2

What cellular structure cause the different results after Gram staining?

A. Mycolic acid

B. Cell wall

C. Flagella

D. Cell membrane

E. Cytoplasm

Question #3

Why is it important that you don’t put too much water to prepare the smear?

A. It will cause the cells to swim away

B. Water may carry contaminants

C. Water can dilute the stain

D. It will take too long to dry the smear

Question #4

Which of the following are the correct order of chemicals used in Gram staining?

A. Crystal violet, iodine, safranin, acetone-alcohol

B. Crystal violet, iodine, acetone-alcohol, safranin

C. Safranin, crystal violet, iodine, acetone-alcohol

D. Iodine, Acetone-alcohol, crystal violet, safranin