a population where there is a single strain or single organism of microbes
normal microbiota
the natural amount of microbes in our bodies
what are sterile/aseptic techniques
procedures used to avoid cross contamination
medium/media
types?
nutrients/food for your microbes to feed on and grow
broth-liquid media
solid media/agar- the solidifying agent is agar, once its mixed its called solid media
how do you know if a broth is sterile
when you gently shake it, look for any cloudiness. if it is clear, it means it is sterile.
how to dispose of a contaminated broth
take it to the kill area. if there is a screw cap on it, slightly loosen the cap before you incubate it or place it in the kill area so that it doesn't explode
what is an agar deep and when do you use it?
-liquid agars that are poured into test tubes and autoclaved
use:
1. you can use them to determine if a microbe is anaerobic by placing them deep in the agar (the butt) where there isn't oxygen
2. when you have to pour your own petri or agar plates, you start by melting agar deeps in a water bath (~mL)
what is an agar slant? use?
it is a tilted agar deep and is used to grow microbes
what are petri/agar plates? use?
invented in 1887 by Richard petri. They are used to hold solid media growth in isolated colonies.
how to keep from cross contaminating petri dishes
-carefully remove them from plastic sleeves
-do not separate the lids from the bottoms or put fingers near interiors (if this happens, mark it with a red X)
how can you tell the lid from the bottom of a petri dish
the lid has a wider diameter than the bottom
5 petri dish rules
-medium/agar is poured into the bottom of dish
-spread microbes on the agar
-place labels on the bottom of the dish
-tape plates together before incubating
-incubate dishes upside down
what do you use inoculating loop and needle for? how do you sterilize them?
to safely transfer microbes from one place to another, and stab microbes into deep agars and agar slants
flaming
place the wire into the Bunsen flame and let it burn bright red. don't forget to let it cool.
what are serological pipettes for?
they're used to measure and transfer specific volumes of liquids and to transfer liquid microbe cultures
Pasteur pipettes
used to transfer small liquid volumes and liquid microbe cultures
use for Bunsen burner
used to burn off contaminating microbes on heat resistant lab equipment
what are slide warmers. optimal conditions?
they are used for drying slides and speeding up evaporation of fluid from smears.
temps 40-50 degrees C.
what are incubators used for? optimal condition?
they are used to maintain stable conditions for cultures to grow.
they are 30 and 37 degrees C
the ones in our locker are ~20-22 degrees C
water are water baths for?
they are used to incubate test tubes are varying temperatures
what is the safety/fume hood used for?
it us used to remove potentially toxic fumes. this is where we put waste containers for toxic liquids. stain waste is in a labeled container under the hood