PBS - 3.1.5 - Isolation

Streak Plate Methods of Isolation

• identification process of an unknown microbe relies on obtaining a pure culture of that organ-

  ism

• method produces individual colonies on an agar plate.

• density decreases, eventually leading to individual cells being deposited separately on the agar sur-

  face.

• A common streaking technique is the quadrant method

• all of the above

Studies microscopic organisms

• Ichthyologist

• Entomologist

• Mammalogist

• Microbiologist

• Mineralogist

Tags

NGSS.MS-LS1-2

The purpose of streaking a plate is to obtain 

• large quantities of bacteria
• bacteria in pure culture

Plates should be incubated

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

What is the first thing you should do?

• put on gloves
• wash your hands
• sterilize your workspace

What is the last thing you should do?

• take off your gloves
• wash your hands
• sterilize your workspace

Why is it important that the Petri plates are incubated upside down?

• To get dense colonies

• To get mat culture

• To get colonies with reduced growth

• To prevent moisture from condensing onto the agar surface

What is the inoculation loop used for?

• Nutrients for bacteria

• Sterilising equipment

• Collecting/spreading bacteria

• Stopping contamination

What is the agar used for?

• Nutrients for bacteria

• Sterilising equipment

• Collecting/spreading bacteria

• Stopping contamination

What is the petri dish lid used for?

• Nutrients for bacteria

• Sterilising equipment

• Collecting/spreading bacteria

• Stopping contamination