Part 1. Write out each of the following Staining Procedures. 50 points.

1. Gram Stain.
2. Acid Fast Stain. Ziehl-Neelsen Method.
3. Endospore Stain.  Schaeffer-Fulton Method.

This must be done without using your lab book. Spell each stain correctly and include the proper time for each step.

Part 2. 50 points. Obtain culture of unknown organism. Write number of culture. Do each of the three staining procedures on your organism. Examine slides with your microscope. Answer these questions.

There are 10 questions to answer, each worth 5 points.

The possible organisms are:

Bacillus megaterium Gram positive rods with endospores, not acid fast

Escherichia coli Gram negative rods without endospores, not acid fast

Mycobacterium smegmatis Gram positive rods without endosores, acid fast

Staphylococcus epidermidis Gram positive cocci without endospores, not acid fast

Your unknown organism will be one of those four. You will be asked to identify the organism, but only 5 points off if incorrect. 

Most students who study do well on this test. Remember, you will not be allowed to use your lab books on any part of the test. If you have any further question, please contact Dr. Ewart.