Frog+Experiment

A.P.E.S. Class November 9, 2011

Frog Experiment:: We will work on the next step during our Friday morning meeting 11?18/2011

During last Wednesday’s class students were presented with the following exercise:

// You observe that a high percentage of frogs, which are especially sensitive to environmental poisons, in small ponds in your agricultural region that have birth defects. Suspecting agricultural chemicals present in runoff from farms to be the culprit. Based on this observation and background knowledge you decide to proceed as a scientist. State a hypothesis in your own words. Next devise an experiment that might help you support or reject your hypothesis. Imagine you conduct the experiment and that it supports your hypothesis. What might those results look like? //

The student team responses were as follows:

Team #1:

__ Hypothesis __ : We suspect the chemical runoff from the farms is causing the birth defects in the pond. __ Experiment __ : We will have an artificial pond. We will take some of the frogs out of the natural pond and place them in our clean pond. We will measure the amount of birth defects in both ponds in two months. __ Results __ : The birth defects will decrease in our artificial pond.

Team #2:

__ Hypothesis __ : We think that a high percentage of frogs have birth defects because of chemicals present from agricultural runoff. __ Experiment __ : Make two frog environments: one with water from the original pond, and one with water from another pond not near the farm. Place frog eggs in each environment (same species).

Team #3:

__ Hypothesis __ : Agricultural chemicals in runoff from farms are causing birth defects in frogs in small ponds. __ Experiment __ : Compare percentage of birth defects in “control” pond (ponds isolated from farms) to the percentage of birth defects in small ponds near farms. __ Results __ : If the results support our hypothesis they would look something like … 5% in control, 75% in dirty pond – worst defects in dirty pond.