Understand the purpose of Gram staining: It is used to differentiate bacterial species into two groups based on the chemical and physical properties of their cell walls.
Recognize the key characteristic of a differential staining technique: It involves using more than one chemical stain to differentiate between different microorganisms or structures.
Identify the steps involved in Gram staining: The process includes applying a primary stain (crystal violet), a mordant (iodine), a decolorizer (alcohol or acetone), and a counterstain (safranin).
Analyze the outcome of Gram staining: Gram-positive bacteria retain the crystal violet stain and appear purple, while Gram-negative bacteria do not and appear pink after counterstaining.
Conclude that Gram staining is a differential staining technique because it distinguishes between Gram-positive and Gram-negative bacteria based on their cell wall properties.