Question

Use the following hypothetical situation to answer the Part C. questions. You live along the Paulinskill River in a rural area of New Jersey known for its growing agriculture industry. This area was also once known for its large bog turtle population. In the last few decades, however, the bog turtle population has decreased to the point that this species is now considered critically endangered. You want to design an experiment to aid in the recovery of the bog turtle population and begin by collecting the following background information-"Contamination by pesticides, agricultural run-off and industrial discharge may negatively affect the bog turtle and its habitat directly. Contaminants may also accumulate in or adversely affect the turtle's invertebrate food supply, such as crustaceans, insects, slugs, snails, and earthworms. Based on this information, you decide to design a lab-based experiment to determine the effect of pesticides on earthworms, a common food source of the bog turtle. 1. Use inductive reasoning to develop a hypothesis for your experiment. 2. State a prediction to test the accuracy of your hypothesis. 3. Complete the experimental design table for a controlled experiment you would design to test your hypothesis Earthworm Experiment Experimental Design Parameters Independent variable Dependent variable Controlled variables (at least two) Control group Experimental group

Answer 1

Answer 1) Inductive reasoning for developing a hypothesis-

Here there are two facts i.e., the bog turtle population is decreasing due to the contamination of the water of its habitat, and contaminants may also impact other living organisms in this habitat such as earthworm which is the main food source of bog turtle.

Therefore, our hypothesis will be, Negative effect of pesticide in Paullinski river on earthworm will lower the population growth of bog turtle.  

Answer 2) Prediction- Increasing pesticide concentration will impact negatively on earthworm population growth that will, in turn, lower the population of bog turtle as earthworms are a common food source of the bog turtle.

Answer 3) Independent variable- Concentration of pesticide in the water. This is because the effect of concentration of pesticide on the population of earthworm will be seen in this experiment.

Dependent variable- Number of earthworms that will survive. This is because the survival rate of earthworm will depend on the concentration of pesticide in the water.

Controlled variable- Temperature of the water, and Volume of the water. These variables will be kept constant so as to minimize the experimental errors.

Control group- Earthworms growing in the clean and healthy water which does not contain pesticide.

Experimental group- Earthworms growing in the water tanks with increasing concentration of pesticide in each tank.