Draft 4/1

In my intro to microbiology lab we have been working with many different gram positive and gram negative bacteria. The easiest way to tell the two kinds of bacteria apart is by doing a gram stain. This stains the outer layer of the bacterial cell. Gram positive bacteria will turn a purple color, and gram negative bacteria will turn a pink color. You have to look under a microscope to determine whether or not the bacteria you are testing is gram positive or gram negative. There are also many other tests that you can run to help see if the organism you are working with is gram positive or gram negative and what that specific organism may be. You can plate the organisms on different types of agar and see what the colonies look like. Also if you plate the organisms on a differential or a selective media you can look and see what kind of reaction happens within the media or if the media suppresses bacterial growth. All of these will be very important in determining what organism you are working with. Tests in a medical lab for these organisms are a lot more straightforward to run and more streamlined in order to get a faster result.