Sherrie Adduci<br />Geoscience P.7<br />October 1, 2010<br />Understanding Systems Lab<br />Introduction:<br />The forest consists of trees, soil, watcher and air, plants and animals. These are the elements of a forest, but the parts alone do not form a system. A living system, which has both living and nonliving parts, is called in ecosystem. Some systems change so slowly they seem as though they do not change at all. Forests may seem that way to people who merely use them for camping, hunting or fishing. In this lab, systems are observed and recorded over time to depict their alterations in an atmosphere filled with natural and artificial lighting, as well as a system with no light at all. As evidenced by figure 1, two lab tubes hold water, two hold an aquatic plant, two hold one tadpole, and two hold both aquatic plant and a tadpole. One group of these tubes resided in the light, while the other stayed in the dark. Elodea is an aquatic plant of a species that include ornate waterweeds. Tadpoles are aquatic larva of an amphibian, including frogs, toads, newt and/or salamanders. They breathe through their gills, and lack legs until the later stages of their development. Through this lab it is discovered how light, or the lack of light, can affect the organisms in an aquatic ecosystem.<br />Research Question: How does the lack of light affect an aquatic ecosystem? <br />Hypothesis: System in the light will survive more, the plant will be fine, tadpoles alone will die, and both together will be content. System in the dark will suffer, all systems will die out at similar times.<br />Materials: <br />
Procedure: <br />The first step one must do in order to create their very own ecosystem is to confine a considerable quantity of tadpoles, water, and plant material from a nearby pond. In an average sized tank, one must hold the tadpoles with pond water and the plant material. One must use eight test tubes and there are two different sections utilized. One section dedicated to remaining in the dark, while the other would reside in the light. Two test tubes need to be filled with water, this is the controlled variable. Two test tubes must be filled with both water and a tadpole, and two test tubes must be filled with water, a tadpole and plant material and two test tubes must be filled with water and plant material alone. Four test tubes, one with a tadpole, one with water, one with a tadpole and plants and one with plant, required stoppers placed on top of the test tubes prior to their placement in the dark atmosphere. <br />Data Observation:<br />
DATEIN THE DARKIN THE LIGHTAugust 23, 2010Tadpole alone is still alive.Water (control) – bluish on top, oxygenatedPlant – not photosynthesizing, giving off carbon dioxide.Tadpole and plant- the tadpole is dead and the water is yellow.Tadpole is alivePlant and tadpole = alive, water has a blue coloring.Plant and water: thicker (photosynthesizing, growing) the water is blue, and the plant is growing new leaves.Controlled water is bluish. August 25, 2010Control has a blue tone.Water and tadpole, tadpole is alive.Just plant = less plant materialTadpole and plant - tadpole is dead, plant is almost dead, floating white substances, fungus too.Just tadpole – dead, yellowish waterTadpole and plant – water color is blue, the tadpole is alive.Just plant – alive, healthy, bluish water.August 29, 2010Just tadpole – alive, no foodTadpole with plant – dead tadpole, plant is dead.Only plant – yellow, plant material looks unhealthy a bit of decomposition.Just the tadpole – decomposing, yellowish waterTadpole with plant – blue water, plant is just as big. Just plant – area of plant is not changing muchAugust 31, 2010Just tadpole – alive, yellowishPlant and tadpole – still dead, mold fungus. Less plant material, yellowish white growthJust plant – mostly deadControlled – stuff growing, bacteria, still blue waterJust tadpole – dissolving, broken up into pieces, no longer visibleTadpole and plant – alive, blue waterPlant only – blue water, plant is aliveSeptember 6, 2010Just plant – yellow, greenish, quantity of the plant it lessTadpole and plant – tadpole is dead, plant is decayingJust tadpole – still alive and activeJust tadpole – dead dissolvedTadpole and plant- plant material is healthy, tadpole is alive, water is blueJust plant – water is blue, greater amount of plant materialSeptember 14, 2010Just tadpole – no movement, yellow waterPlant – on to the decomposing mode, dying, yellowishPlant and tadpole – tadpole is dead, in four different piecesTadpole and plant – both are alive, water is blueJust plant – alive, green, blue water (bluer than controlled group)Just tadpole – tadpole is disintegrated, the water is murkySeptember 27, 2010Tadpole is dead and the plant is still somewhat alive, it is dying.Just plant – dead, yellowJust tadpole –disintegrate in piecesJust tadpole – all disintegrated but brown material are at the bottom of the test-tubeTadpole and plant – dead tadpole, plant is aliveJust plant – alive, increased size, blue water.
0228600<br />Figure 1<br />Conclusion:<br />In some ways the hypothesis is correct, the system in the light did survive better than the system in the dark. As predicted, the plant in a test tube alone flourished and remained alive, while the tadpole in a test tube alone disintegrated at the bottom of the test tube and died. But, the hypothesis was wrong in predicting that the test tube that held both the plant and the tadpole, the plant lived and the tadpole did not. There are no specific alterations I would make if this lab were done again, because the lab is about a system and what is necessary to keep a system alive. We are testing this, so we don’t want every system to be alive and perfect in the end, because the flaws help us to discover the answer to the research question. The lack of light effects an ecosystem drastically because compared to the system in the light, the system in the dark killed the tadpole and plant in the same test tube, killed the plant that was alone and destroyed and killed the tadpole that was alone. <br />