Student's Assignment:

1.  What can be the first step done to identify the organisms present in a sample of stool collected from a patient who is suffering from severe diarrhea?
2. What if the smear you prepare becomes too dense?
3. What is gram variability? How can it affect your results?
4. What is meant by Gram indeterminate organisms?
5. What is the advantage of the Gram stain over the simple stain?
6. What is the  theory about the mechanism of the Gram-stain reaction?
7.  Which step is the most crucial or most likely to cause poor results in the Gram stain? Why?
8. Why must young cultures be used when doing a Gram stain?
9. What part of the bacterial cell is most involved with Gram staining, and why?
10. What is the function of the iodine solution in the Gram stain? If it were omitted, how would staining results be affected?
11. What is the purpose of the alcohol solution in the Gram stain?
12. What counterstain is used? Why is it necessary? Could colors other than red be used?