| Explore | We know that all plants undergo cellular respiration and we want to see if temperature affects the rate of cellular respiration. |
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| Research Question | How does temperature affect cellular respiration? |
| Predictions | Our prediction/hypothesis for the experiment is that cellular respiration will take place at a faster rate in warmer temperatures, than cooler temperatures. |
| Experimental Design | Materials: 70 Germinating peas, 100 mL graduated cylinder, DI water, 5 vials, 5 steel washers, Absorbent cotton balls, 15% potassium hydroxide (KOH), Non-absorbent rayon, 5 graduated pipets, 5 stoppers, 2 trays (1 green, 1 black), Hot water bath, Red food coloring, Thermometer, Hot plate, Fridge. Plan: Make 5 respirometers and put 2 in a hot water bath, 2 in a tub of water in the fridge, and 1 in a tub equlibilerated to room temperature. The one at room temperature is our control and we will see if hot water or cold water affects the rate of cellular respiration. We will be measuring the rate of cellular photosynthesis by taking reading of the respirometers every 5 minutes for 25 minutes. |
| Conclusion | After completing our experiment, we were given varied results. Our control respirometer, which was tested at room temperature (24°C), started to increase quickly and then after about 10 minutes the rate of increase started to level out. After 25 minutes of cellular respiration, our control respirometer had a volume reading of 0.285 mL of oxygen. We tested two respirometers in cold water (7°C) for 25 minutes. At the end of the 25 minutes, we discovered that the beginning point was lower but then it started to increase rapidly. At around 15 minutes, the temperature increase started to level out. Lastly, we tested two respirometers in a hot water bath. Our original plan did not work out because when we placed it in the water (42°C), the red food coloring immediatelu shot out of our respirometer. We believe that this is because the heat from the water expanded, not leaving enough room for our food coloring. We then started another trial with two respirometers at a slightly lower temperature (32°C). We found that cellular respiration occured at a much faster rate than our other temperatures. After 25 minutes, the average volume of oxygen absorbed was close to double our results of our other trials, finishing at about 0.52 mL. |
| Investigation Theme | POS |
| Grade Level | High School Students (Grades 9,10,11,12) |
| School Name | Mother of Mercy High School |
| Session | Fall 2016 |
