OpenStax 2.4 Staining

What is the primary purpose of staining microscopic specimens?

• To change the shape of the specimen

• To make the specimen transparent

• To add color and contrast to the specimen

• To increase the size of the specimen

Which of the following is a basic dye commonly used in staining?

• Rose Bengal

• Eosin

• Acid Fuchsin

• Crystal Violet

What is the role of a mordant in the Gram stain procedure?

• To stabilize the stain or dye

• To counterstain the cells

• To act as a primary stain

• To decolorize the cells

Which staining technique is used to differentiate bacteria with waxy cell walls?

• Gram staining

• Acid-fast staining

• Endospore staining

• Flagella staining

What is the purpose of fixation in specimen preparation?

• To increase the size of the specimen

• To attach cells to a slide and preserve their structure

• To make the specimen transparent

• To change the shape of the specimen

Which of the following is a negative stain?

• Crystal Violet

• Methylene Blue

• Safranin

• India Ink

What color do gram-positive bacteria appear after Gram staining?

• Pink

• Green

• Blue

• Purple

Which of the following is NOT a differential staining technique?

• Simple staining

• Endospore staining

• Acid-fast staining

• Gram staining

What is the primary stain used in the Ziehl-Neelsen acid-fast staining method?

• Carbolfuchsin

• Methylene Blue

• Crystal Violet

• Safranin

Which of the following is a common fixative used in chemical fixation?

• Water

• Acetone

• Formalin

• Ethanol