Aseptic Technique and Performing Isolation Streaks

The purpose of streaking a plate is to obtain 

• large quantities of bacteria
• bacteria in pure culture

When streaking a plate, primarily

• flex and extend the fingers
• move from the wrist 
• move your whole arm

Plates should be incubated

• agar side up
• agar side down 
• it doesn't matter

When streaking a plate, you should go back over the last area

• never
• 1-2 times
• 3-4 times
• 8-10 times

When streaking a plate, the lid should be

• placed on the bench top, top side up 
• placed on the bench top, inside surface up
• should be held in the same hand as the plate 
• should be held in the opposite hand from the plate

When streaking a plate, the loop should be flamed

• At the beginning and end 
•  At the beginning and end and between the first 2 zones 
• At the beginning and end and between the second and third zone 
• At the beginning and end and between each zone 

George streaks a plate of medium from a broth culture.  After incubation, he sees confluent growth in all sectors.  Which of the following errors could NOT explain this result?

• He forgot to pick a colony from the plate
•  He forgot to flame the loop between sectors
• He picked additional culture from the plate after the first sector
• He crossed over the previous streak too many times at the beginning of a new sector.

Which finger should you use to remove the lid from a test tube when you are using an inoculating loop to make a transfer? 

• little finger of the dominant hand (hand holding the loop)
• little finger of the non-dominant hand (hand holding the sample)
• forefinger of the dominant hand (hand holding the loop)
• thumb and forefinger of the non-dominant hand (hand holding the sample)

The bacteriology loop should be sterilized in what part of the Bunsen burner flame? 

• in the bright blue cone
• just above the bright blue cone
• above the flame
• at the base of the flame

The loop should be held 

• straight up and down
• at a very slight angle
• at a fairly steep angle
• parallel to the work bench