Biology Lab One
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?
ANS: As the dissolved oxygen levels of the water increase that the population of the fish increase as well.
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.
Ans: The population of the fish in the water is proportional to the oxygen dissolved.
3. What would your experimental approach be to test this hypothesis?
Ans: To take and test different water samples and measure the oxygen dissolved levels with the fish population to see if the same results are achieved.
4. What are the independent and dependent variables?
Ans: Independent variable would be the dissolved oxygen. The dependent variable would be the fish population.
5. What would be your control?
Ans: In controlling the dissolved oxygen you can control the fish population.
6. What type of graph would be appropriate for this data set? Why?
Ans: There are several graphs that could be used. However, it would be better understood from either a line graph or a column graph. This information would not be well suited for a pie chart.
7. Graph the data from the table above.
Ans: See attached chart.
8. Interpret the
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?
ANS: As the dissolved oxygen levels of the water increase that the population of the fish increase as well.
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.
Ans: The population of the fish in the water is proportional to the oxygen dissolved.
3. What would your experimental approach be to test this hypothesis?
Ans: To take and test different water samples and measure the oxygen dissolved levels with the fish population to see if the same results are achieved.
4. What are the independent and dependent variables?
Ans: Independent variable would be the dissolved oxygen. The dependent variable would be the fish population.
5. What would be your control?
Ans: In controlling the dissolved oxygen you can control the fish population.
6. What type of graph would be appropriate for this data set? Why?
Ans: There are several graphs that could be used. However, it would be better understood from either a line graph or a column graph. This information would not be well suited for a pie chart.
7. Graph the data from the table above.
Ans: See attached chart.
8. Interpret the