User:Jess Kowall/Notebook/Biology 210 at AU

January 28, 201-JK Identifying Algae and Protists of the Transect

    Lab 2 featured hay infusions made of soil samples from transects, made in lab last week. The purpose of this experiment was to utilize the hay infusion in order to identify different algae and protists living in each individual transect of land. This objective had secondary goals of learning how to use a dichotomous key to identify unknown protists and algae, understanding different traits and characteristics of the different algae and protists in the transect, and to carefully examine algae and protists from the transect. The dichotomous key is a step by step direction in identifying each of the organisms under the microscope, by examining characteristic and matching them to a guide. Using the dichotomous key, the organisms were sorted into the algae, which are the photosynthesizing organisms, and the protist, which is the nutrient-consuming organism. A serial dilution was also made from the transect's hey infusion cultures for examination in a later lab. 
    The materials used in this experiment included the hay infusion culture from the transect, a dichotomous key for identification, wet mounts made from the top and bottom of the hay infusion, and agar treated petri dishes and sterile broth tubes for the serial dilution. After practicing using the dichotomous key on known organisms, wet mounts of the hay infusion culture were made, with care to represent different niches of the ecosystem. These were examined under the microscope, and the protists and algae present were identified with the dichotomous key. Following this identification portion of the lab, the serial dilution was made. This was done with four sterile broth tubes, in which the first contained 100 microliters of the culture, and then 100 microliters of that mixture was added to the next tube, and then so on, so that each of the four tubes contained and exponentially diluted amount of the original hay infusion culture. This same process was done on agar treated petrol dishes. 
    The hay infusion culture from the American University Community Garden had mold and algae growing over the top layer of the ecosystem, and had a strong smell reminiscent of dirty lake water. There were small white dots spotting the surface of the culture as well. The rest of the culture was a mixture of different dark green colors, depending on what niche of the ecosystem was being examined. When taking samples from different niches, it was seen that some samples were taken from close proximity of plant matter, and some were not. Because protists are nutrient-consuming organisms instead of making their own food, it is reasonable to believe that many of the samples near plant matter will contain protists, and that algae will be found further away from other plants, as they are photosynthesizing organisms. There were five samples pulled from the hay infusion culture: three from the bottom area of the culture, and two from the top area of the culture. There was plant matter in the vicinity of the samples pulled from the top. When using the dichotomous key to identify present algae and protists, it was found that paramecium bursaria, spirostomum, blepharisma, pandorina, paranema, and paramecium multimicronucleatum. The paramecium bursaria measured approximately 80 micrometers, is motile, and is classified as a protozoan. The spirostomum measured approximately 2 micrometers, is motile, and belongs to the protist category. The blepharisma measured approximately 100 micrometers, and is a motile protist. The pandorina measured approximately 140 micrometers, and is a motile organism belonging to the algae category. The paranema measured approximately ten micrometers, and is a motile protist. Lastly, the paramecium multimicronucleatum measured approximately 160 micrometers, and is a motile protist. The only photosynthesizing organism identified was the pandorina, the only algae found in the culture. If the hay culture was left to grow for another two months, the algae population would probably remain relatively the same, because the protists use their nutrients for food, but the competition for protist would grow, especially since the plant matter originally present in the soil samples will die out because of a lack of reproduction. The pandorina satisfies the five conditions for life because it is composed of cells, participates in an energy exchange when it uses photosynthesis, utilizes information exchange with its surroundings in order to be able to undergo photosynthesis, is able to reproduce by asexual and sexual reproduction, and it can be assumed that the pandorina is continually evolving. NOT FINISHED 

January 26, 2014-JK Transect Introduction: American University Community Garden

    In lab 1, a transect of land was assigned to each group for observation. This lab was performed in an effort to practice characterizing the layout of a niche of land, with regards to its location, topography, and the organisms inhabiting it. The twenty by twenty meter transect of land assigned to each group was an example of biological diversity on American University's campus, and was also demonstrative of how complex a small niche of land can be. The transects featured both abiotic components, or nonliving things, and biotic organisms, or living things. The lab was an important step in understanding the components of an ecosystem, or a community of biotic and abiotic organisms. 
    Each group of students was assigned a twenty meter by twenty meter transect of land on campus, and was instructed to chart the topography, location, and inhabitants of the area of land. A soil sample was taken of the transect for further study in the lab. 
    Transect 4 was located in the American University Community Garden,  a square of land that features four planting areas. The majority of the topography consisted of soil which was partially frozen from the cold temperatures, and the area of land surrounding the planters was a mixture of mulch/straw and soil. Two of the four planters had vegetation growing inside them, one with smaller plants and the other with tall plants, and the other two planters were simply filled with soil. A drawing of the transect is attached. The abiotic components of the transect included the soil and straw/mulch mixture and the planters. The biotic organisms included the two kinds of plants in the planters, and the bugs in the soil and on the plants. It can be assumed that there were also protists too small for the human eye to see living among the plants and soil. 
    The given transect was an example of a community because it featured a collection of species, and can be called an ecosystem because it is a larger representation of a community. The transect had identifiable abiotic and biotic components, which were listed in the discussion and can be seen in the transect diagram. The transect was an important piece of information in observing the qualities and characteristics of a niche of land, and yielded a significant amount of information for a relatively small piece of land. The transect also yielded a sample of soil for further study in the lab. 

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