A colleague performs a smear prep from a colony on an agar plate. Without staining it, he looks at it under oil immersion with a light microscope (1000x magnification). “Hm," he says, "it's not purple, so it must be gram negative." Briefly explain the error in his logic, and say what he would have to do to show whether the organism is gram negative or gram positive. Your Answer:

A colleague performs a smear prep from a colony on an agar plate. Without staining it, he looks at it under oil immersion with a light microscope (1000x magnification). “Hm," he says, "it's not purple, so it must be gram negative." Briefly explain the error in his logic, and say what he would have to do to show whether the organism is gram negative or gram positive. Your Answer:

Basic Clinical Laboratory Techniques 6E

6th Edition

ISBN:9781133893943

Author:ESTRIDGE

Publisher:ESTRIDGE

Chapter7: Basic Clinical Microbiology

Section7.7: Bacterial Identification And Antibiotic Susceptibility Testing

Problem 2CS

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