| what are microbiological media | Microbiologists use bacterial culture media for many purposes and application. They contain everything that bacteria needs for growing outside the body under laboratory conditions. |
| What are media used for | Isolate and identify bacteria,
Reveal their metabolic properties,
And allow long-term storage of pure cultures. |
| what do taxonomic description of bacteria include what kind of information | about their cultural requirements |
| what means some bacteria are classified as auxotroph's | even given a carbohydrate carbon source, they cannot synthesis one or more organic molecules required for their growth – these molecules must be also provided in growth media. |
| what does when a bacteria is fastidious | meaning that they have very specific and/or complex nutritional requirements. |
| can fastidious grow/not and why/why not | These species do not grow because they cannot use one or more nutrients in the form provided in the medium (e.g, they might require H2S rather than SO4 as a sulfur source), have requirements for very specific types of nutrients (such as certain complex organic molecules), and/or require unusual growth conditions (such as growth in living cells or at high temperature or pressure). |
| what is one of the factor that greatly influence bacterial growth | their oxygen requirements. |
| four principal types of culture media | complex media
defined media
selective media
differential media |
| complex media | Pasteur, Koch, and Tyndall typically prepared media by boiling animal or plant materials to extract nutritive molecules.
Modern complex media contain extracts of beef (peptone), milk (tryptone), soybean meal (soytone) or yeast.
the protein in these extracts are broken down into small peptides and amino acids.
the specific amount of these molecules is not precisely determined
their wide assortment allows complex media to support a wide range of bacterial types. |
| defined media | formulated from pure substances at predetermined concentrations.
the exact chemical composition of defined media is known precisely.
often used to determine the nutritional requirements of bacterial species. |
| selective media | complex or defined media will also be classified as selective if they support the growth of only certain types of bacteria
this media can be made selective through the addition of substances that enhance or inhibit the growth of particular types of bacteria. |
| differential media | reveals specific metabolic or metabolic characteristics of bacteria grown on it.
the most powerful tools available to a microbiologist because it reveals a wide range of information about an organism very quickly. |
| what is MacConkey Agar | medium that is selective for gram-negative bacteria and will indicate whether the bacteria ferment lactose |
| how do microbiologists mix media | Microbiologists traditionally mixed media by combining the individual components listed for a recipe. |
| how do media is prepared | 1. simply dissolving the powder in water
2. sterilizing the solution
3. dispensing it into culture vessels, |
| Two of the largest suppliers are | BBL and Difco laboratories |
| what is TSB | Tryptic Soy Broth, which is designed to support the growth of a wide range of bacterial types.
is a complex type of medium |
| differences between anaerobic and aerobic bacteria | Aerobic bacteria's needs oxygen to survive, while anaerobic does not. |
