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Name: Margie
Status: Other
Grade:  Other
Location: OH
Country: United States
Date: January 2007

How might the Gram stain technique be of value in establishing the purity of a culture of bacteria?

If all of the cells in a culture are Gram positive, this would tell you that there are no Gram negative cells in the culture. But you must do many additional test like cell morphology, colony morphology, sugar fermentation tests plus other tests in order to conclude that it is a pure culture.

Ron Baker, Ph.D.

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