User:Lauren Lit/Notebook/Biology 210 at AU
2/16/14 - Lab 3:Microbiology and Identifying Bacteria with DNA
Materials and Methods:
1.Using the swirled up Hay infusion from Lab 1 and 2, 100 ml of the hay infusion culture was added to 10mls of nutrient broth into a tube. This made a 1:100 dilution or 10^-2. Next 100microliters from that tube was placed into 10mls of nutrient broth to make a dilution of 1:10,000 or 10^-4. Next 100microliters from tube 4 was placed into 10mls of nutrient broth to make a dilution of 1:1,000,000 or 10^-6. Next 100microliters from tube 6 was placed into 10mls of nutrient broth to make a dilution of 1:10,000,000 or 10^-8.
2. Four nutrient agar plates were labeled. 10^-3, 10^-5,10^-7,10^-9. Another set of Agar plates with tetracycline were labeled with the same labels.
3. 100 microliters of the 10^-2 solution was placed on the surface of the 10^-3 agar plate and the 10^-3 agar plate with tetracycline. 100 microliters of the 10^-4 solution was placed on the surface of the 10^-5 agar plate and the 10^-5 agar plate with tetracycline. 100 microliters of the 10^-6 solution was placed on the surface of the 10^-7 agar plate and the 10^-7 agar plate with tetracycline. 100 microliters of the 10^-8 solution was placed on the surface of the 10^-9 agar plate and the 10^-9 agar plate with tetracycline.
4. The plates were inoculated at room temperature for 1 week.
5. The plates were observed
Observations and Data: Table 1: 100-Fold Serial Dilution Results
- 10^-3 --> 120 Colonies --> 1,200,000 colonies/ml - 10^-5 --> 30 Colonies --> 30,000,000 colonies/ml - 10^-7 --> 4 Colonies --> 400,000,000 colonies/ml - 10^-9 --> 21 Colonies --> 1.7*10^-10 Colonies/ml - 10^-3 + Tetracycline --> 23 Colonies -->230,000 Colonies/ml - 10^-5 + Tetracycline --> 1 Colonies -->1,000,000 Colonies/ml - 10^-3 + Tetracycline --> 1 Colonies -->100,000,000 Colonies/ml
Table 2: Colony Observations:
-10^-5 Nutrient Agar --> Dark Purple, Circular, Entire edge, Flat --> 1 colony --> Quick motility with cilia --> Gram negative -10^-5 Tetracycline --> Cream, circular edge -->1 colony --> brownian movement (drifting) -->Gram negative -10^-3 Tetracycline --> yellow, small, convex, entire edge --> 230,000 colonies --> no movement --> Gram positive
Results and Conclusions: There is some antibiotic resistance on the 10^-3 tetracyline plate. This is seen when comparing the number of colonies on the Nutrient agar plate and the tetracline plate. There are less colonies on the nutrient plus tetracycline plates compared to the just nutrient plates. This indicates the antibiotics are working to kill the bacteria. If the bacteria grew anyway, which is known as antibiotic resistance. There is clear evidence that the presence of the tetracycline is enough to really prevent and limit bacteria growth. there is roughly 25species of the bacteria which were unaffected by the tetracycline.
The gram stain performed showed us that the bacteria from plate 10^-3 with tetracycline is gram positive and is antibiotic resistant to tetracyline. while the other 2 samples from 10^-5 and 10^-5 with tet. were both gram negative. Both gram positive and gram negative are known to have species that are resistent to tetracyline. LL
2/9/14 - Lab 2: Identifying Algae and Protists
Introduction: Understanding and Identifying Unicellular Organisms, specifically Algae and Protists. Algae and Protists have very specialized characteristics. While they are different organisms they both come from a common ancestor and are both unicellular eukaryote.
Materials and Methods: - A wet mount was created using 8 different known organisms --> A drop of the specimen solution containing various organisms were placed on the slide and covered with a coverslip -The wet mount and specimens were viewed under tthe microscope -Once an organism was located it was characterized using a Dichotomous Key
Observations and Data:
1. Euglena - 20-25 micrometers - multicellular 2. Chlamydomonas - 10 micrometers - multicellular 3. Paramecium Caudatum - 180 micrometers
-Smalls musty -mold is growing on the sides -Leaves and plants are on the top layer -Algae is growing on the very bottom of the jar -algae coating on the top.
-Top of Jar: Brown Algae
-Immobile -10 micrometers in length
-Bottom of Jar:
-Spirostimum -brown algae -Colpidium - 62 micrometers
Conclusions: The hay infusion is expected to grow more mold agae and other organisms. The smell is expected to get progressively worse. The niches are expected to become more specialized and more organisms with more distinct roles will develop. LL
1/31/14 - Lab 1: Biological Life at AU
The objective of Lab 1 Proceedure 1 is to understand Natural Selection. To get an understanding of natural selection 3 members of the volvacine line were observed under the microscope. They included Chlamydomonas, gonium, and volvox.
Chlamydomonas Number of cells: 1 Colony Size: 23 Functional specialization Cells: Flagellum for movement and chloroplast
Gonium Number of cells: 75-100 Colony Size: 3 Functional specialization Cells: Flagellum
Vovox Number of cells: about 500 Colony Size: 1
Picture to be added here.
The objective of part 2 is to understand the biotic and abiotic aspects of a niche at American University outside the Katzen Arts Center.
Abiotic Factors Pebbles, large rocks, little rocks dead leaves wood chips bricks soil
Biotic Factors Cotton Tails Red Bushs Grass Weeds
Picture to be added here.
In the future I will be going back to the niche to observe any changes that may have occured to the factors, individually and how they interact together. LL.
Good start. Could be improved with more substance. Address red text from protocol include detailed descriptions, analysis and conclusions. For more instructions see TA notebook. SK
1/26/14 - Lauren Lit's Lab Notebook - Bio210. LL