Aseptic Technique Flashcards
GO FOR UNO!!!
all organisms are descendants of one organisms
pure culture
In working with microorganisms, we must have:
sterile-nutrient-containing-medium
method of transferring organisms (inoculum)
method of transferring organisms from pure culture to sterile medium
inoculum
techniques to maintain aseptic condition
aseptic technique
performing lab work that greatly reduces the risk of contamination
aseptic technique
What is the proper flame?
small blue cone
What are the different techniques in transferring the inoculum into tubes?
Aseptic Pipetting
Slant to Slant
Slant to Broth
Broth to Slant
Deep Agar Stab
When do you use inoculating needle?
Deep Agar Stab
What arm would you use in holding the stock culture, agar and broth?
non-dominant hand
what hand will you use in holding the inoculating needle/loop?
dominant hand
How do you unscrew the test tubes?
use little finger and ring finger
Why must the loop be cooled?
to prevent from killing microorganisms that are not resistant to heat
In getting culture, what must the amount be?
small
If agar surface is wet, what must be done?
wipe with sterile swab
How deep will you stab agar?
1 cm
how long will you incubate culture?
48 hours
What are the techniques in transferring the inoculum to petri plate?
Streak Plating
Spread Plating
Pour Plating
Dilution
spreading source material over an agar surface until one microorganism at a time fall off the loop
streak plating
single type of microorganism that originated from a single cell
colony
how many bacteria/mL can you see in pond water?
10^5 to 10^6
how many bacteria/mL can you see in soil?
10^8
how many bacteria/mL can you see in turbid culture of Escherichia coli?
10^7
how many bacteria/mL can you yield from an agar plate?
10^3 to 10^5 colonies
method employed to plate a liquid sample for the purpose of isolating or counting the bacteria present in that sample
spread plate technique
A perfect spread plate technique will result to visible and isolated colonies of bacteria that are evenly distributed in the plate and are countable. (t or f)
True
most commonly applied for microbial testing of foods or isolating and identifying microbial flora present in environmental sample
spread plating
What are the glasswares required in spread plating?
screw capped tube
sterile pipettes
glass spreader
What is the medium required in spread plating
plate count agar
nutrient agar
How many test tubes must be prepared in dilution?
6 test tubes containing 9 ml of sterile distilled water
What is the rotation angle of petri dish in spread plating
45 degrees
The plate in spread plating must be incubated for:
37 degrees; 24 hours
method for counting the number of colony-forming bacteria present in a liquid specimen
pour plating
pour plate is more precise than streak plate (t or f)
true
pour plate gives a lower count since non-heat resistant microorganisms can die in pouring molten agar. (t or f)
true
optimum count of colonies in pour plating
30-300 colonies per plate
The plate in pour plating must be incubated for:
37 degrees; 24-48 hours
colonies on the surface will be smaller than embedded colonies in pour plating
false (embedded colonies will be smaller)
