Antibiotics Effects On Bacteria

Effects of Different Antibiotics on Bacteria Because of their small size, rapid rate of reproduction, and relatively simple structure, bacteria are excellent subjects for laboratory studies. This investigation will introduce you to techniques of microbiology that will be of use to you throughout your biological work.
Procedure
1. Heat the test tubes of sterile agar medium in the water bath until the agar melts. 2. Remove the test tubes from the water bath. Let them cool enough to hold in your hand, but not so much that the agar becomes solid again. Perform the following transfer as quickly as possible. You must work rapidly so that the liquid agar will not cool and solidify before the transfer is completed. 3. Hold both a test tube
After a few minutes turn the dish upside down. Let it stand at room temperature, or in an incubator, to allow the bacteria to grow. Observe the dish the next day and on several following days. Describe the color and shape of any bacterial colonies and other features you observe.
Data and Observations While this picture that I have included on the back of this report may not be very clear, it shows the diameter of the lack of bacteria surrounding the different antibiotics.With the Erythromycin, there was 4.3 cm of a complete lack of bacteria around it. With the Streptomycin, there was 2.5 cm of a complete lack of bacteria around it. Finally, the Penicillin had 1.8 cm of a faint amount of bacteria, but still had traces unlike the Erythromycin and Streptomycin.
Discussion
The Erythromycin had the highest diameter of complete lack of bacteria around it, followed by Streptomycin, and lastly, the Penicillin. The Erythromycin obviously was able to fight against the bacteria the best, which could be because of a variety of different reasons. One of them is that possibly the bacteria had built up more of an immunity against the Streptomycin and Penicillin because it had already fought against it before. Also, quite simply, the Erythromycin may have worked the best against the bacteria because it had the best particular skill set to fight against
I do think that more than one species of bacteria is present in my petri dish, simply because if there wasn't more than one species, the Penicillin would have completely wiped out the bacteria surrounding it. Since there was slight traces of bacteria still around the Penicillin, I've come to the conclusion that there must be more than one species of bacteria. 2. The areas surrounding the Erythromycin and Streptomycin are completely free of bacterial colonies. The Erythromycin has a diameter of 4.3 cm that is free of bacterial colonies. The Streptomycin has a diameter of 2.5 that is free of bacterial colonies. This is because Erythromycin and Streptomycin are antibodies that are designed to completely wipe out the surrounding bacteria. In a sense, they were just doing their job. 3. The clear area around the Erythromycin is 2.5 cm larger than the clear area around the Penicillin, because the area around the Erythromycin is 4.3 cm, while the area around the Penicillin is 1.8 cm. It can even be argued that the Penicillin has no clear area at all, because there was still traces of bacterial colonies around the