1. The analysis of water in a lake or stream depends upon more than one field of science or body of knowledge. Suppose you stumble across a portable water-testing lab on a riverbank, and you find two testing stations: (1) a light microscope and glass slides; and (2) a package of pH (acid/base) test strips and a digital thermometer. But you find no scientists. Match each testing equipment station to the field of science to which it belongs, and hypothesize what is being tested in each station. (6 points) 2. Technology has affected society by causing radical changes in how people live. For example, the use of pesticides has increased the amount of food available to people. Describe another example of how technology has changed the way people live. (5 points) 3. Describe what eDNA is. Evaluate the use of eDNA in the monitoring of a difficult-to-track species of fish in a river. (5 points) 4. Investigate energy in a prairie ecosystem. a. Use an example to describe how the first law of thermodynamics is observed in a prairie ecosystem. (2 points) b. Compare the albedo of the prairie to the albedo of another type of ecosystem or biome. Be sure to mention which is higher. (2 points) c. How are local energy systems in the prairie related to global systems

Experiments in environmental toxicology can sometimes be manipulative experiments in which the researcher actively chooses and manipulates the independent variable. in hunt's study, for example, dosages of bpa were manipulated and the effects were measured. in manipulative studies, the researcher controls all the other variables in the experiment, so any health effects observed in the test subjects can be attributed to differences in the independent variable. in other cases, researchers use natural experiments in which the dependent variable (typically a measure of organism health) is measured under differing contexts that are not manipulated. say, for example, that an accidental chemical spill contaminates five ponds. to determine the possible effects of the toxic chemical on frogs, a researcher could compare the hatching rate of frog eggs laid in those five ponds to the hatching rate of eggs laid in five uncontaminated ponds nearby. this would be an example of a natural experiment because concentrations of the toxic chemical in the ponds were not controlled by the experimenter, but rather resulted from the chemical spill. drag type of experiment on the left to the example of experiment on the right. blood concentrations of bpa in college students are compared to their recent manipulative consumption of canned food items 2. the feeding behavior of fish in streams that receive acidic runoff from strip mines is compared to the feeding behavior of fish in unaffected streams. the deformity rate in baby birds from nests in pesticide-sprayed fields is compared to the deformity rate in birds from nests in unsprayed fields 4 tumor development is compared in mice exposed to five dosages of a known carcinogen in the laboratory foraging activity levels are compared in tadpoles exposed to four concentrations of toxic metals in the laboratory. growth of corn plants is compared in field plots sprayed with three different dosage: s of weed killer 7 bpa concentrations in the urine of people with diabetes are compared to bpa concentrations in the urine of people without diabetes - natural; manipulative