In the previous entry we explained the process of creating a simple stain. It is now time to uncover the mysteries of the bacteria found on both the bathroom door and the spout of the drinking fountain! Today will be the last time we test the sample from the drinking fountain because we were unable to obtain a pure culture with a single colony. Here are the exciting results of our simple stains!
To view the bacteria, we had to put the compound light microscope to the highest power. A HUGE 400x! To get enough light to clearly view the specimen, we had to use immersion oil. Immersion oil prevents light from refracting (or bending) so that the microscope has a higher resolving power. This resolving power is needed to see the bacteria clearly.
The bacteria found on the drinking fountain:
Proper identification of this specimen cannot be made because there were two errors in the execution of the procedure. First, we had too much sample, creating a slide with overlapping bacteria. Second, and most importantly, we heated the specimen too long, altering the bacteria. This is another reason we are dropping this sample from further exploration.
The bacteria on the bathroom door handle:
The same two mistakes were made when making this slide; however, the bacteria was identifiable to a greater extent. It appears to be of the cocci category, and more specifically, in the staphyl (or cluster) arrangement.
After viewing our slides, we removed "F" from the incubator, finding more bacteria!
To prevent overgrowth, we moved "F" into the refrigerator for next class. We had to create two slants because we have to use one tube for the experiments and retain one tube as a back-up.
The pure culture of the bacteria found on the door handle was also left in the refrigerator for next class for the same reason.
What fate do they await? Come back next week to see!
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