Quality Control on Media

Perform this lab in partners:

1. Turn to the portion of your laboratory manual that describes the individual media and find what quality control organisms are required for each medium and record on the provided Media Evaluation Form.

2. Check your sheets from last week and determine whether your media passed their quality control.

3. Did any of the media not pass the quality control and how should this be resolved? Top.

Streak Fresh Plates for Known Organisms

1. Divide the twenty culture organisms from last week between classmates.

2. Streak them on fresh blood or chocolate agar according to standard protocol. (Review the Streaking Evaluation Check List before streaking)

3. Place them in the appropriate environments for tomorrow's lab.  Top.

Direct Gram Stains and Comparison with Growth on Plates at 24 hours

1. Read each Direct Gram Stain to determine the types of organisms that may be present and record on Direct Gram Stain and Colony Growth Comparison Form

2. Look at the accompanying plates, determine the different colony types and describe them.

3. Compare your answers with your fellow classmates and then determine how many gram stains to perform

4. Gram stain each different colony.

5. Indicate how the Direct Gram Stain compared with the plate growth and colony types.  Top.

Rapid Tests

You may work in teams:

1. You have observed demo's for each of the rapid tests.

2. Collect culture plates streaked yesterday, reagents, and materials.

3. Perform catalase and oxidase on each of the cultures and record the results on your pink and blue Media Sheets from last week.

4. Catalase is not usually done on the Enterobacteriaceae family, but it may aid in a quick separation between organisms by distinguishing which are immediate and which are delayed. Top.

Enterobacteriaceae Catalase Reactions

Top.

Review Competency Evaluation and Discuss Preparation for Next Week's Lab

Next week we will performing Patient Unknowns on Urine Cultures.  Using material from your lecture notes, laboratory manual and last week's lab, answer the questions following the example Competency Evaluation:

Go to: Competency Evaluation