What is meant by gram staining

Question

What is gram staining and what is difference between gram positive and gram negative bacteria

Answer 1

Gram staining is the process of dyeing a sample of cells, usually bacteria, with a violet dye. The significance of this is that it helps scientists determine the composition of the cell wall of a particular sample.

Gram-positive samples are purple because their cell walls have peptidoglycan which prevents the purple dye from washing out of the cell. Gram-negative cells are stained red because the purple dye is washed out of the cell, leaving only the counterstain inside the cell. This implies that Gram-negative cells do not have a cell wall or do not have a thick layer of peptidoglycan that can prevent the purple dye from washing away during the staining process.