Plant ecologists have conducted experiments to determine how enhanced levels of atmospheric cárbon dioxide affect the growth of plants and one of the plants that has been studied is poison ivy. It turns out that enhanced levels of carbon dioxide promotes faster growth of poison ivy and makes it more allergenic. From the description of one of these experiment below, indicate the following: a. hypothesis b. the treatment (independent) variable c. treatment levels (also indicate which one is the control) d. response (dependent) variables e. Standardized variables f. Expected results based on information provided above. An ecologist obtained 30 similarly size poison ivy plants from a forest and planted them in individual pots, all of which were the same size. The plants were all grown in the same type of soil, and provided the same amount of water and light. The ecologist placed 10 plants in a greenhouse with 410 parts per million (ppm) carbon dioxide (this is the current level in our atmosphere). The ecologist placed 10 plants in a greenhouse with 450 ppm carbon dioxide (elevated carbon dioxide). The ecologist placed 10 plants in a greenhouse with 500 ppm carbon dioxide (highly elevated carbon dioxide). After 6 months the ecologist measured the weight of the plants and the urushiol content (urushiol is the oil poison ivy produces that causes an allergic reaction).
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The hypothesis is that ivy grown with higher carbon dioxide concentration is larger and more poisonous. ** Show more…
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