What Are Culture Media? Culture medium is a solution of nutrients that are necessary for bacteria growth. The medium needs to contain a source of carbon and nitrogen in order for the bacteria to grow. If agar is added to the solution, the medium will be semi-solid at room temperature and can be in the form of a culture plate or slant.

Image courtesy of Austin Community College
Agar is made from seaweed so that is the reason for the awful odor when heating media.

Image courtesy of Barry's Free Photos
If agar is not added then the culture medium will remain liquid and it is called a broth.

Image courtesy of University of Texas-Health Science Center at Houston
Types of Media
Purchase of Media
Preparation of Media
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Introduction to Bacteriology
Staining
Culturing
Classifying

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Last updated: 08/07/03