Question

Goldfish Respiration Experiment

Mr. Jones’ ninth grade class is studying the influence of temperature on respiration rate in goldfish. Each of his 24 students has a single goldfish isolated in a goldfish bowl half full of de-chlorinated tap water at 15°C. Each student is allowed to add a random amount of either chilled tap water (5°C) or warmed tap water (30°C) very slowly for 5 minutes to gently adjust the temperature of the water in the bowl. The goldfish are allowed an additional 5 minutes of acclimation time after the temperature in the bowl has equilibrated. Then each student records the temperature of the water to the nearest 0.1°C using a digital thermometer and the goldfish respiration rate (the number of times the operculum or gill cover opens) during a 60 second period. The class hypothesis (H₁) is that respiration rate (cycles / min) will increase with increasing temperature (°C).

The independent variable is temperature and is continuous. The dependent variable is respiration rate and is continuous. The observations are paired in the sense that each temperature has only one respiration rate. However, there is a clear expectation from the class hypothesis that the independent variable is causing the change in the dependent variable.

Scenario 2 – Class Data for the Goldfish Respiration Experiment

Student	Temperature (°C)	Respiration rate (cycles / min)
1	15.0	20
2	13.5	18
3	17.9	25
4	24.3	36
5	18.2	28
6	12.4	17
7	11.9	16
8	14.3	19
9	16.5	23
10	13.2	18
11	15.9	21
12	21.3	32
13	22.7	34
14	12.2	16
15	10.9	15
16	25.2	40
17	6.3	11
18	9.3	14
19	15.1	20
20	13.4	18
21	5.1	10
22	8.3	12
23	9.2	13
24	11.4	15

Scenario 2 – Multiple Choice Questions – Goldfish Respiration Experiment

1. Which of the following is the test statistic (observed) for this experiment?
   1. SE = 1.564
   2. F = 600.36
   3. df = 22
   4. intercept = -1.114

4. Using the relationship you measured between temperature and respiration rate, calculate the expected temperature where respiration rate would equal 0.
   1. 0.739
   2. 1.5072
   3. 24
   4. 1.84 x 10^-17

Answer 1