a pure culture is needed when using liquid media as it cannot be used to differentiate a mixed culture.
selective media
Pure broth culture is a liquid media, used to propagate large numbers of microorganisms. Where as Slant cultures are semi solid media containing a solidifying agent (usually agar). Can be used in determining bacterial motility and in promoting anaerobic growth.
Agar
Culture media in microbiology is a media where microorganisms like bacteria from a sample is grown into colony for the identification of particular organism.eg-simple media like blood agar,choclate agar
Culture medium is a gel or liquid that aids in the growth of cells and microorganisms. The type of culture media that is used can vary.
There are various types of microbiological media used for culturing microorganisms, such as agar plates for solid media, broth for liquid media, selective media to encourage growth of specific organisms, differential media to distinguish different types of organisms based on their growth characteristics, and enrichment media to help grow fastidious microbes.
Some different characteristics of a goo culture media is the different personifications that are being depicted in the media .
The nutreint media which reamin in liquid form through out the culturing process is called liquid media. It is different to solid media in not having agar in it which is the solidifying agent used in medium prepration. Commonly prepare liquid media is nutrient broth which contain beef extract, partially digest protein (peptones) and sodium chloride.
there's an excellent explanation here http://forums.biotechinstitute.org/showthread.php?t=93
Enriched media are the selective media in which substances like blood,serum,egg etc are added to the basal medium. They are used to grow the bacteria which are more exacting in their nutritional needs. eg-blood agar- enriched with blood loeffers serum slope-enriched with serum lowenstein jensen media-enriched with egg
a pure culture is needed when using liquid media as it cannot be used to differentiate a mixed culture.
it is a type of media used for the growth of obligate anaerobes.
The three media of sound are solid liquid and gas.
THE PRESENCE OF A GREEN SLIME OR THE GROWTH OF ALGEA. Onother view: If talking about liquid broth medium in laboratory then it can be estimated by the increase in turbidity which is caused by increase in number of microbial cell and we can observe it by spectroscopy.
selective media
In this media non-complicated ingredients are used to support the growth of microbes