One of your lab partners has followed the recommended procedure of running Gram-positive and Gram-negative control organisms on her Gram stain of an unknown species. Her choices of controls were Escherichia coli and Bacillus subtilis. She tries several times and each time concludes she is decolorizing too long because both controls have pink cells (one more than the other). What might you suggest she try and why?

One of your lab partners has followed the recommended procedure of running Gram-positive and Gram-negative control organisms on her Gram stain of an unknown species. Her choices of controls were Escherichia coli and Bacillus subtilis. She tries several times and each time concludes she is decolorizing too long because both controls have pink cells (one more than the other). What might you suggest she try and why?

Basic Clinical Laboratory Techniques 6E

6th Edition

ISBN:9781133893943

Author:ESTRIDGE

Publisher:ESTRIDGE

Chapter7: Basic Clinical Microbiology

Section7.4: The Gram Stain

Problem 2RQ

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