Chemically defined medium

Definition

A chemically defined medium contains only known quantities of all its chemical components. This allows for precise control over the nutritional and environmental conditions for microbial growth.

5 Must Know Facts For Your Next Test

1. Chemically defined media are used to study the nutritional requirements of microorganisms.
2. All ingredients in a chemically defined medium are pure chemicals, usually salts and organic compounds.
3. These media are essential for experiments requiring reproducibility and consistency.
4. They do not contain any unknown or variable components like those found in complex media.
5. Chemically defined media can support the growth of specific microbes that have particular nutritional needs.

Review Questions

• What is the primary advantage of using a chemically defined medium over a complex medium?
• Why is it important that all ingredients in a chemically defined medium are known?
• How does a chemically defined medium aid in studying microbial nutrition?

Related terms

Complex Medium: A type of growth medium that contains some unknown composition, often made from extracts or digests.

Selective Medium: A type of culture medium designed to favor the growth of specific microorganisms while inhibiting others.

Differential Medium: A culture medium that allows differentiation between different types of microorganisms based on their biological characteristics.