User:Morgan M. Wright/Notebook/Biology 210 at AU

BIO 210- Lab #2 Identifying Algae and Protists 7/2/15

INTRODUCTION Most protists and algae are too small to see with the naked eye. We use a microscope to allow us to view these micro-organisms. A dichotomous key is used to determine which organism is being observed. It works by running a series of questions which exclude certain known organisms. The questions ask about color, size, and the forms of motility.

METHODS The Hayes infusion jar was retrieved. It had separated into a biofilm on top and sediment on bottom. Two samples were taken from two niche areas of the jar. We chose to take two samples from directly above the sediment on the bottom of the jar and two samples from just under the biofilm the surface of the jar. We used these samples to create a wet mount and observed organisms under a microscope. We used a Dichotomous key to assist in identification of the organisms. We also created a serial dilution derived from our Hayes infusion. There were 8 plates containing nutrient solution, 4 of which contained an anti-biotic. The dilutions were 10^-2, 10^-4, 10^-6, and 10^-8.

RESULTS We identified 4 organisms. Gonium (90um) and Peranema(60um) were identified in the samples taken near the surface. Stentor (1mm), Colpdium(50um), and Spirostromium (1mm) were identified from the sample taken near the bottom. The jar appeared to have some mold on the surface. The jar smelled like manure and was very offensive to the nose. There was no evidence of plant life such as green shoots. Organisms who live near the biological matter in our Hayes infusion are either eating the biological matter or consuming those who are eating the biological matter. All of the organisms we observed are non-photosythetic. If the Hay infusion culture grew another two months, I would expect to see more and more of fewer and fewer species as certain organisms out compete each other for the limited amount of resources in the jar. Peranema is alive because it is comprised of cell(s), it uses energy, it reproduces (passes down information), and it evolves and in doing so fills a niche in the micro-ecosystem that is the Hayes infusion.

Picture of Hayes Infusion Jar IMG_4982.jpg Picture of Spirrostromium IMG_4987.jpg Picture of Serial Dilution diagram. Photo.jpg

DISCUSSION We found many more organisms than the 5 we identified including some the Dichotomous key was unable to assist in identification. Through viewing organisms from our Hayes infusion under a microscope, we gained an better understanding of the biotic factors of our transect and of American University's environment. Upon viewing our serial dilution we will be able to better observe what biotic organisms had been living in the soil in my transect.

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BIO 210- LAB #1 The Transect and Volvocine Line 6/30/15

INTRODUCTION Simply put, a transect is a slice of land. We chose a transect on American University's campus and observed both the biotic and abiotic features of the ecosystem to which our transect belongs. From our transect we can extrapolate about the abiotic and biotic features of other transects on American University's campus. My transect was marshy but there was no standing water.

METHODS A 20 foot by 20 foot transect was charted out by hand between McCabe, Clark, and Gray hall. Various biotic and abiotic factors of the transect were observed. Pictures were taken to document the transect. A soil sample was also taken for a Hayes infusion in which 10 grams of soil was mixed with 500ml of water and .1g of dried milk in a jar. The jar was then shaken and left to sit with its lid off for a period of 2 nights.

RESULTS The transect was in the sun most of the day with no shade until the sun almost sets. There was a slight slant to the land with the southern side of the transect slightly sloping to the northern side. The isolation of the transect led to very little foot traffic relative to other grassy areas of American University's campus. The soil was very moist. There were breaks in the vegetation coverage on the ground revealing small rocks mixed in with the clay-like soil. There was also moss between the patches of grass. The dominant plant appeared to be clover which covered up the majority of the ground in the transect however, grass and weeds also were present. Some additional biotic factors we observed were several squirrels running around our transect and the tress closest to our transect as well as birds who flew in and out of our transects space. Abiotically, the sun, wind, and air/ground temperature undoubtedly influence what my transect looks like in different seasons. Furthermore, the high clay content in the soil is an abiotic factor which influences the high moisture content of the soil. The file below was taken on the 90 degree northernmost corner of my transect and is looking south east across the transect to the other 90 degree corner of the transect. Total_View.jpg The files below illustrate the vegetation found in my transect. IMG_4997.jpg IMG_4998.jpg IMG_4996.jpg DISCUSSION: Observing my transect provides an insight into the ecosystem at American University. There were many biotic and abiotic features of my transect. In preparing a Hayes infusion, I will be able to observe more of the biotic features under microscope.

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