Where's the Bacteria?

Problem:

Hypothesis:

Materials:

Procedure:

Streak Plate Instructions

1. Lay petri dish on a level surface with the lid side up.

2. Remove the cap of an Easygel bottle. Do not touch the rim or inside of the bottle, or petri dish.

3. Pour all the liquid Easygel into the dish bottom. Replace the lid.

Gently swirl to cover the bottom.

4. Wait at least 45 minutes until the Easy gel is solid.

 

Bacteria Collection

 

 

 

 

 

Bacteria Growth

1. Place the petri dish in the incubator set at 38-40 degrees Celcius for 48 hours.

2. Remove the dish from the incubator and observe the bacterial growth. If possible, count the colonies in each section of the plate and record.

 

 

Questions:

1. Why was it important to set aside one petri dish that was never opened after being prepared?

 

 

 

 

2. Why was it important to have one petri dish that was opened at the same times that another one was, but nothing was spread on it?

 

 

 

 

 

3. How did the appearance of each section compare to the others?

 

 

 

 

 

 

4. Where in this lab could error have occurred? Could the bacteria on the petri dishes have come from somewhere other than where you collected it?

 

 

 

 

 

 

 

 

To

Intro Page