A microbial growth media tube for cultivation of betahemolytic Streptococci. A bacitracin tablet has been added on the media to recognize type A Streptococci. Since most of the type A Streptococci are sensitive to the antibiote bacitracin there will not be growth of type A Streptococci in the vicinity of the bacitracin tablet.
<a href="//commons.wikimedia.org/wiki/User:P%C3%B6ll%C3%B6" title="User:Pöllö">Pöllö</a>
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