Growth medium

An agar plate – an example of a bacterial growth medium. It is a 'streak plate': the orange lines and dots are bacterial colonies

A growth medium or culture medium is a solid or liquid containing nutrients. It is designed to support the growth of microorganisms or cells, or small plants like moss. There are different types of media for growing different types of cells.

There are a wide range of growth media used in biology. Some of the basic types are:

  1. Undefined versus defined media: with defined media we know exactly what chemicals are in them.
  2. Selective media: for example, a medium with an antibiotic added. The only things which grow are those resistant to the antibiotic.
  3. Differential media: these distinguish one microorganism type from another growing on the same plate.
  4. Transport media: these have just enough to let organisms survive.
  5. Enriched media: contain extra amino acids and other building blocks. Used to harvest a wide range of organisms from a particular source.

References

  1. ↑ Madigan M. & Martinko J. (eds) 2005 (2006). Brock Biology of Microorganisms (11th ed.). Prentice Hall. ISBN 0-13-144329-1.{{cite book}}: CS1 maint: numeric names: authors list (link)
  2. ↑ Hadeler, Birgit; Scholz, Sirkka & Reski, Ralf 1995. Gelrite and agar differently influence cytokinin-sensitivity of a moss. Journal of Plant Physiology 146, 369–371.
  3. ↑ Ryan K.J. & Ray C.G. (eds) 2004 (2004). Sherris Medical Microbiology. 4th ed, McGraw Hill. ISBN 0-8385-8529-9.{{cite book}}: CS1 maint: numeric names: authors list (link)