Question

Explain the function of each reagent used in Gram staining.

Answer 1

The function of each reagent used in Gram staining is crystal violet stains all cells purple, Gram's iodine stabilizes the stain in Gram-positive cells, alcohol selectively removes the stain from Gram-negative cells, and safranin counterstains the decolorized cells pink.

Step-by-step explanation:

The function of each reagent used in Gram staining is as follows:

1. Crystal violet: It is the primary stain used in the Gram staining procedure. It gives all cells a purple color.
2. Gram's iodine: It acts as a mordant or setting agent that helps in stabilizing the crystal violet stain in the cell walls of Gram-positive bacteria.
3. Alcohol: It is the decolorizing agent used to selectively remove the stain from Gram-negative cells while leaving the stain intact in Gram-positive cells.
4. Safranin: It is the secondary stain added after decolorization. It counterstains the decolorized cells pink, allowing the visualization of Gram-negative bacteria.