Quiz 3 Flashcards
Why do we use the streak plate technique
To obtain pure isolated colonies
Why is streaking done?
To create a diluted gradient
How many colonies should we have during the standard plate count method?
25-250 colonies
What are the 3 physical forms of media?
Liquid or broth
Semisolid contains agar
Solid contains agar
What is liquid or broth ?
To spread or propagate large numbers of microorganisms
What is semisolid contains agar?
To determine bacterial motility and anaerobic growth
What is solid contains agar?
To observe COLONY appearance, for pure culture isolation, storage of culture, observe specific biochemical observations
What is media ?
Nutrient preparations that are used for culturing microorganisms
What are the two medias?
Synthetic, or non synthetic or growth
What is autoclave ?
Use of pressure chamber at 121 Degree And 15 lb Of Pressure for 15 Min Or Longer Of Pressure
What is dry heat sterilization?
Pipettes and petri dishes in electric oven at 160-170 degrees for 2 hours.
What is ultraviolent radiation sterilization?
Use of radiation at 260 nm to sterilize air and exposed surfaces.
What is Ethylene oxide gas used for?
Heat sensitive material such as plastics (microbicidal and sporicidal)
What is filtration used for?
cannot undergo heat, this process removes bacteria and larger microorganisms
