Gram stains are a very basic technique that can be used in the lab to help identify a type of bacterial cell. The process is very easy. First you want to streak a little bit of your sample on to a microscope slide. If the sample is liquid this is fine but if the sample is solid you must first add a drop of water to the slide to make sure that you can spread your sample out on the slide. Once this smear dries you can then heat fix it by passing the slide through a flame very briefly two times. You then apply a few drops of crystal violet to the slide and let them sit there for one minute. After the minute is up wash off the crystal violet with water. Next you repeat this process with Iodine. Next you place a few drops of ethanol on the slide and let them sit for 10 seconds. This washes away any previous stain done. Next you add safranin which is a differential part of the stain. Any gram negative cells will appear as pink, the color of safranin and any gram positive cells will appear as purple because they retained the purple color from the first round of stains.
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