Scientific Method

Exercise 1:

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, what patterns do you observe? The data in table 2 shows that the dissolved oxygen in the water is calculated by increment of two’s. It show that the more fish you have in the water the more dissolved oxygen you have. The data also suggest that once you get a certain number of fish (15) the dissolved oxygen still tends to increase by two even when the amount of fish decrease.

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. The number of fish in a body of water determines the measurement of dissolved oxygen in the same body of water.

3. What would your experimental approach be to test this hypothesis? To test an area of water with no fish and test the amount of dissolved oxygen. Then test an area with few fish, test for dissolved oxygen and increase the number of fish until I could establish a pattern to support my hypothesis.

4. What are the independent and dependent variables? Independent variable dissolved oxygen. The dependent variable is the number of fish.

5. What would be...