Ch 2: Studying Microbes Flashcards
What are the 5 “I’s” of the Microbiology lab?
- Inoculation - specimen placed in artificial growth environtment
- Incubation - growth
- Isolation - separate species of interest
- Inspection - Observe results
- Identification - determine species identity
What is inoculation?
Creating a culture from a specimen
- flame sterilize inoculating loop (aseptic)
- Collect specimen, transfer to agar dish
- also can transfer to broth tube
What is incubation?
For each microbe, culture, requires time and temp
What is a culture medium?
Artificial growth environment
-Liquid media (broth) or solid media (agar)
What is a selective medium?
contains growth inhibitor that inhibits growth of many bacteria
What is a differential medium?
contains biochemical indicator that changes color to show an acid is produced during fermentation of a sugar
What is isolation?
A dilution technique used to separate microscopic cells
-grow macroscopic colonies (pure cultures)
What are the different methods of isolation?
Loop dilution and Streak Plate
What is inspection (part of the 5 I’s)?
Looking at:
1) Microscopic appearance
2) Cellular metabolism and function
3) Genetic and Immunological characteristics
Which of the 5 I’s uses the loop-dilution technique?
Isolation
What are the components of a selective broth medium for the growth of staphylococci?
- Protein rich nutrient extract
- Salt
- Water
What is resolution?
measurement of the clarity of the image produced
-dependent on wavelength of light source
WHat is light microscopy?
Uses Glass lens that causes light refraction resulting in magnification
What are the parts of the light microscope?
Ocular Lens = what you look through
Objective lens = the different magnifications
Condenser lens = focuses light
Light source = bulb
How do you create contrast in cell structures?
Differential staining
- Gram Stain
- Acid-fast stain
- Spore Stain
