Hi,
Differential media or indicator media distinguish one microorganism type from another growing on the same media . This type of media uses the biochemical characteristics of a microorganism growing in the presence of specific nutrients or indicators added to the medium to visibly indicate the definning characteristics of microorganism. Example - blood agar.
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Greetings!

Differential media contain compounds that allow groups of microorganisms to be visually distinguished by the appearance of the colony or the surrounding media, usually on the basis of some biochemical difference between the two groups. Examples of differential media include: Blood agar (used in strep tests), which contains bovine heart blood that becomes transparent in the presence of hemolytic.

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