Introduction to Science Lab

Introduction to Science

Lab 1 Part 1

Exercise One:

1. The pattern I noticed in the information in table 4, is that the dissolved oxygen always goes up by twos, even after the amount of fish has dropped.

2. My hypothesis for relating the amount of DO measured in the water and the number of fish observed is this; No fish produced no dissolved oxygen, but one or more fish did. Therefore, the production of DO is contingent upon there being at least one fish in the study area, because as the fish leave they do not take the DO with them. The amount will still increase with each new fish that comes into the study area even when there are more fish leaving than entering.

3. To test this hypothesis I have a tank of water with no fish set at a controlled temperature, over a controlled period of time, and a tank with the same water with one fish controlled at the same temperature over a controlled period of time and I would measure the DO level every ten minutes or so. To test the theory that the number of fish (as long as there is at least one) does not matter for the rate of DO production, I would add a few additional tanks with a different amount of fish in each, with the same water, same temp, and same type of fish, for the same amount of time and take away a fish and or add a fish every ten mins or so.

4. The dissolved oxygen is the dependent variable, while the number of fish is the independent variable.

5. The control for this experiment would be a tank of water with no DO and no fish.

6. A line graph would be appropriate for this set of data, because it shows the relationship between the two variables as opposed to a bar graph where the items being graphed are independent from each other.

7.