Differential stains:​ Gram staining​

What happens when Gram positive comes into contact with dye crystal violet?

• Turns pink/red

• Turns purple/blue

• Turns Green/pink

• Turns brown/orange

In Gram-Positive bacteria, what is the cell wall primarily made of?

• Peptidoglycan

• Phospholipid

• Cellulose

• Chitin

Who developed Gram staining?

• John Smith

• Sylvester Graham

• David Johnson

• Christian Gram

How thick is the cell wall of Gram Positive Bacteria?

• 20nm

• 26nm

• 25nm

• 24nm

What is the primary purpose of Gram staining?

• To identify the size of bacteria

• To determine the shape of bacteria

• To differentiate between Gram-positive and Gram-negative bacteria

• To measure the growth rate of bacteria

What color do Gram-negative bacteria turn after Gram staining?

• Purple/blue

• Pink/red

• Green/pink

• Brown/orange