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Gram Positive/Negative
The kingdom Monera is split up into two different groups called archaebacteria and eubacteria. There is a way to stain Monera to distinguish whether it has one of the two types of cell walls, gram positive or gram negative, and see what groups of Monera it belongs in. Bacteria are stained in with a violet dye and iodine, rinsed in alcohol, and then stained again with a red dye. The structure of the cell wall reveals the response. Gram-positive bacteria have cell walls with a lot of peptidoglycans, which traps the violet dye. Gram-negative bacteria have less peptidoglycans, which is between the plasma membrane and the outer wall. The violet dye easily rinses off the cell, but the red color stays on.