Dissolved oxygen is oxygen that is trapped in a fluid, such as water. Since virtually every living organism requires oxygen to survive, it is a necessary component of water systems such as streams, lakes and rivers in order to support aquatic life. The dissolved oxygen is measure in units of ppm—or parts per million. Examine the data in Table 2 showing the amount of dissolved oxygen present and the number of fish observed in the body of water the sample was taken from; finally, answer the questions below.
Table 2: Water quality vs. fish population
Dissolved Oxygen (ppm)
0
2
4
6
8
10
12
14
16
18
Number of Fish Observed
0
1
3
10
12
13
15
10
12
13
1. Based on the information in Table 2, what patterns do you observe? Based on the information in Table 2 there is a pattern of 2ppm oxygen with 1 fish observed then 4ppm and 3 fish observed and once it goes to 6ppm there is more fish observed of 10 and it peaks at 12ppm then starts going down on the number of fish observed in a pattern of 10, 12, 13, and 15.
2. Develop a hypothesis relating to the amount of dissolved oxygen measured in the water sample and the number of fish observed in the body of water.
My hypothesis would be if there is more dissolved oxygen in the water area then there would be more fish in the area that each sample is taken.
3. What would your experimental approach be to test this hypothesis? I would do similar to this and would test the dissolved oxygen in various areas of the water and track the amount of fish in those areas with lastly comparing the results.
4. What are the independent and dependent variables?
Independent variable is the dissolved oxygen with the dependent variable being the fish.
5. What would be your control?
There wouldn’t be a control.
6. What type of graph would be appropriate for this data set? Why?
A line graph would work best with this data set because it would provide the clearest results of