Quiz 2 Micro Lab Flashcards
Define culture media:
Culture media is defined as the nutrient material containing all of the necessary macronutrients and growth factors needed to grow microorganisms in the lab.
Define culture:
The microbes that grow that grow and multiple in or on the media is referred to as culture.
Differenciate between Chemically defined media and complex media
Chemically defined media is one in which exact chemically composition is KNOWN.
While
Complex media is one in which the exact chemical composition is not known.
Differentiate between a ‘selective’ ‘differential’ and an ‘enrichment’ media:
Selective media contains one key ingredient which inhibit the growth of 1 group of bacteria, but allow another group of bacteria to grow.
Differential media is culture media that contains one key ingredient that allows you to differentiate one bacteria from another based on if they metabolize that key ingredient or not.
Enrichment is usually a liquid media that contains additive to enhance the growth of a population of bacteria that is normally present in very small amounts.
The three types of solid medias are
The three types of solid medias used in a lab are:
1.Agar plates
2.Agar slants
3.Agar deep
Culture media that is used in microbiology can be prepared in various forms. These include broth media and solid (agar) media. What are these medias:
Agar Slant: Test tubes containing a solid medias. Media was solidified on an angel.
Agar Plates: Petri dishes that contain a shallow layer of solidified media.
Agar deep: Tubes that contain solid media that was allowed to solidify upright.
What is inoculation?
Inoculation is the introduction of bacteria into sterile media to keep them alive, to study their growth and to perform various test.
What are the two different instruments used for inoculation?
What are their differences?
- An inoculation loop
Consist of a wire or loop at the end. - An inoculation needle
Consist of a wire with a straight end.
All of the media used in microbiology is sterile. To sterilize culture media, what instrument is used?
The instrument used to sterilize culture media is called Autoclave. A close chamber that puts steam under pressure.
What is the standard conditions used to autoclave culture media?
The standard conditions used to autoclave media is
120 degrees Celsius, 15 psi, 15 to 30 minutes.
What are some disadvantages of Broth media?
1- It do not allow for the separation of organisms.
2- Differentiation of living and dead bacteria cannot be made.
What is the disadvantage of Agar plate culture media?
1- The media can dehydrate within several days.
What are the disadvantages of Agar slants?
1- They do not allow for the separation of different bacterial species
What are some disadvantages of Agar deep?
1- They do not allow for the separation of different bacterial species
