Jelly Case
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5. The sterile disk was successful. The agar was clear and my disk dissolved.
6. As my hypothesis stated, I did not see any contamination in my sterile water.
7. The streak for isolation with S. marcescens on a TSA plate using the drag-lift technique was not very successful. My streak technique is not very good. I streaked near the middle of the agar, when I now know that I should stay near the sides as to not cross quadrants twice. I did see some isolation, but not as much as I had expected.
8. My streak with E. coli and Chromobacterium violaceum was not very successful. I saw colonies of purple and colonies of beige, meaning I correctly separated the two, but they were not very isolated. I did see a few isolated colonies, about 4 or 5. I did see a little contamination in one of the quadrants. It looked very fuzzy and umbonate.
9. My streak with E. coli and Serratia marcescens was successful. My streaking technique was good, because I saw very many isolated colonies and my aseptic technique improved because there was no contamination at all. The colonies were a red color with a little beige tint.
10. I did see very many isolated colonies for our table streak. This is because the table has all types of things on it. Our hands, our experiments, books, and even though it is disinfected after every class, we can see that that is still not enough to keep things sterile.
11. The cough plate surprisingly had no growth at all. I think its because maybe we did not properly cough into the agar. I expected this one to have the most growth, but I was wrong.
12. The finger plate had 14 colonies, and I expected more growth than that. I believed the finger would have the second most growth because our hands are exposed to so many organisms.
13. The head plate had the most colonies. Although the table had the biggest colonies, the head plate had lots of punctiform colonies all around the agar.
14. For the exposed plate, we did not see any growth at all. My hypothesis was correct, and the reason why I expected no growth was because I did not expect the air to have very many contaminants. I put it near the sink, and maybe if I had put the plate in a high traffic area, for example, in the middle of our lab table, I might have seen some growth.
15. E. coli is a facultative anaerobe, so growth was seen in both places. Facultative anaerobes can grow with or without oxygen, because they can make ATP by aerobic respiration and fermentation if oxygen is not present. I predicted it to grow in both places because I knew that it was a facultative anaerobe. It spiraled and created sediment when shaken, which is what E. coli should do.
16. Pseudomonas is an obligate aerobe, which means it needs oxygen to grow, so growth was not seen in the anaerobe jar or the bottom of any agar. Growth was always seen at the top. 17. Clostridium in anaerobic jar had lots of growth as I expected. Our stab was not successful, because we probably went too deep, but clostridium produced gas which is what caused our agar to crack.Clostridium