User:Amie S. Krupnick/Notebook/Biology 210 at AU

Identifying Algae and Protists January 28, 2015

Purpose The purpose of this experiment was to observe the transect sample in the hay infusion culture after one week. A week in the hay infusion culture allowed time for algae and protists to appear, reproduce and thrive. This experiment made use of a dichotomous key, which allowed accurate identification of different organisms. If a hay infusion culture is created and then observed after one week, multiple different life forms (algae and protists) will appear and be viewable under a microscope for analysis and observation. This experiment also called for the preparation and plating of serial dilutions, which will be used in the coming week.

Materials and Methods In this observational experiment, the hay infusion culture was brought to the work station. Using transfer pipettes, two different wet mounts were made with samples from different parts of the culture (top and bottom). Each sample was observed under a microscope to identify different living organisms. A paper and pen was used to draw picture of the observed organisms (Images 1-6). After sample collection was complete, the hay infusion culture was returned to the back table. Part II of the experiment dealt with preparing and plating serial dilutions. To do this, three tubes of 10 mls sterile broth were labeled 10^-2, 10^-4 and 10^-6. Three nutrient agar plates and three nutrient agar plates with tetracycline were obtained and labeled accordingly. One plate from each of the two groups was labeled 10^-3, 10^-5 and 10^-7 with initials, date and group number. Using a micropippetor set at 100 ul and a box of tops, 100 ul of broth from tube 10^-2 was added to tube 10^-4 and mixed. That step was repeated two more times to make the 10^-4 and 10^-6 dilutions (Image 7). To plate the serial dilutions on the agar nutrient plates, 100 uL was pipetted from the 10^-2 plate. A glass spreader soaking in alcohol and run through a bunsen burner was used to spread the dilution evenly across the agar nutrient plate. The same procedure was repeated for the rest of the plates, including the +tet plates. Agar nutrient plates with tetracycline were all covered in aluminum foil and both sets of plates were set in the back of the room to incubate for one week.

Data and Observations The hay infusion appeared brown in color and had a very putrid odor. The odor was particularly strong with the culture was moved, allowing sealed in smells to escape. There was no life, such as mold or green shoots, apparent on the surface of the liquid. Two samples were taken from the culture- one from the surface of the liquid and one from the bottom of the culture. After observation and analysis, the sample from the top resulted in three different organisms- Chlamydomonas, Colpidium and Paramecium Bursaria (Images 1-3).

Image 1: Chlamydomonas, 5 um

Image 7: Serial Dilution

Work Cited Bentley, M., Walters-Conte, K., Zeller, N. (2015). Identifying Algae and Protists. General Biology II, 1(1), 18-24.

1.27.15 Good first lab book entry. The transect diagram is a little simple. List biotic and abiotic features. SK

Biological Transect: Observing a Niche at American University January 26, 2015

Purpose The purpose of this experiment was to observe a 20x20 transect at AU for the Biology-210 lab. This experiment and the corresponding set of observations will act as the basis for future experiments, using the samples collected during this initial inspection of the transect. After taking a sample of abiotic and biotic components from the transect, the plot of land was discussed in class. This lab was purely observational and did not yield any findings. A Hay Infusion was created with the collected sample to aid in the following week's lab.

Materials and Methods In this observational experiment, each group was given a flashlight and a sterile 50 ml conical tube for sample collection representative of the transect. After being dropped off at the appropriate transect, the 20x20 plot of land was examined and drawn for reference. The transect is located in the gardens between Hughes Hall and Bender Arena and a concrete pathway running from north to south. The allotted plastic tube was filled with dirt, soil and vegetation from the transect. The transect was drawn, with directions labeled (Image 1). Upon return to the lab, a Hay Infusion Culture was made from the collected sample. 10 grams of soil and vegetation from the conical tube sample was placed in a plastic jar containing 500 ml of deer park water. 0.1 g of dried milk was added into the jar and the jar was mixed. After being labeled, the jar was set down without a lid for a week.

Data and Observations This transect is located on an uneven plot of land that contained many different forms of vegetation (see Image 1). The vegetation found was largely evenly distributed across the transect. The biotic organisms specified are: trees, leaves, bushes, vegetation and shrubs. The abiotic components specified are: snow, dirt, hay, wood chips and paper. During the making of the Hay Infusion Culture, dried milk was added as a source of food for the vegetation in the culture.

Image 1:

Conclusion The jar was set in the back of the lab without a lid for examination of protists and to "inoculate agar petri plates for studying bacteria" (Bentley et al 2015) in the following week.

Work Cited Bentley, M., Walters-Conte, K., Zeller, N. (2015). Biological Life at AU. General Biology II, 1(1), 13-17.

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