Chapter 3 - Tools Of The Laboratory Flashcards
What are the Five I’s
Inoculation, Incubation, Isolation, Inspection, Identification
What is a culture?
Cultivation of micoorganisms, appears in or on the medium after incubation
What is a nutrient-containing environment in which microbes can multiply?
Medium (plural: media)
What is inoculation?
Introduction of microbes into media for culture
What is it called when an instrument for sampling or inoculation is considered free of microbes?
Sterile
What is incubation?
The use of an incubator to create the proper growth temperature and other conditions.
What does microbial growth in liquid medium look like?
Cloudiness, sediment, scum, color
What does microbial growth on solid medium look like?
Colonies: visible masses of piled-up cells
What is the usual temperatures used in labs?
20 to 45°C
What is another word for sterile?
Aseptic meaning without contamination
What are the three categories of media classification?
Physical State, Chemical composition, and Functional Type(purpose)
What category is liquid, semisolid, and solid classified in?
Physical State
What is liquid media?
Water-based solutions that do not solidify at temperatures above freezing and flow freely in a tilted container
What physical state exhibits a clot-like consistency at room temperature?
Semisolid media
What is used to determine motility of bacteria
Semisolid media
What does semisolid media localize a reaction to?
Specific site
What provides a firm surface upon which cells can form discrete colonies?
Solid media?
What does solid media isolate?
Bacteria and fungi
What is a complex polysaccharide isolated form the red alga Gelidium?
Agar
What does it mean when a medium has agar in its name?
The medium contains 1 to 5% agar
What is the media called whose exact compositions are known?
Defined (synthetic) media
Defined media may contain what compounds that do not very from one source to another?
Pure and inorganic compounds
Complex media contains at least one components that is what?
Chemically definable
Which media contains extracts of animals, plants, or yeasts?
Complex media
Blood, serum, meat extracts or infusions, milky, yeast extract, soybeans digest, and peptone are considered examples of what?
Complex media
What is in a rich mixture of nutrients for microbes that have complex nutritional needs?
Nutrient broth, blood agar, and MacConkey agar
What media grows as a broad spectrum of microbes?
General purpose media (nonselective)
General purpose media is a complex media that contains a mixture of ingredients that support what?
A wide variety of microbial life
What is enriched media?
Contains complex organic substances that fastidious bacteria require for growth
Selective Media contains one or more agents that do what?
Inhibit the growth of certain microbes
What media is important in primary isolation of a certain type of microorganism from a mixed sample?
Selective Media
What does differential media do?
Allow multiple types of microorganism to grow, but display visible difference between colonies
What media shows differences in colony size or color, media color changes, or formation of gas bubbles or precipitates?
Differential media
Why are possible reasons for variations in differential media?
Variations may be due to metabolism of certain ingredients that cause color change