| Explore | |
|---|---|
| Research Question | Photosynthesis in different temperatures. |
| Predictions | The leaves in the hot water might rise faster because theres more pressure and possibly more carbon. |
| Experimental Design | Use spinach leaves in different temperatures of water with baking soda and use a lamp to see how quickly the leaves rise. We will use hot water, ice water, and room temperature water to measure the speed of photosynthesis at different temperatures. |
| Conclusion | Our results are inconclusive because we were not able to take any data. None of the leaves floated to the surface. A possible explanation for our results could be that spinach leaves are not able to conduct photosynthesis in extreme temperatures. Our “room temperature” water sample was actually 17 degrees celsius, which is fairly cold. It’s possible that none of the leaves floated to the surface because their photosynthesis was hindered by the extreme temperatures. This would explain why the leaves did float in our previous experiment, in which temperatures were constant, but did not float in this experiment where we used more extreme temperatures. The fact that we were not able to collect any data since no leaves floated to the surface supports our claim that photosynthesis is hindered in spinach leaves by extreme temperatures. Leaves floating to the surface is a sign that photosynthesis is occurring, and since none floated up, that indicates that photosynthesis did not occur. Our claim is strengthened by the fact that leaves did float to the surface and photosynthesis did occur in our previous experiment in which we used room temperature water only. This indicates that the change in temperature specifically was what prevented photosynthesis. In the future, we could replicate the experiment using more samples with a greater range of temperatures. We could have a sample that is actually room temperature, the control, and then many other samples that deviate slightly or greatly from room temperature. By using this wide range of temperatures, we could see at what temperature exactly photosynthesis stops occurring. We would measure this by observing how (if at all) the rates of photosynthesis slow as temperatures deviate from room temperature, and at what temperature no leaves float to the surface, showing that no photosynthesis is occurring. |
| Investigation Theme | POS |
| Grade Level | High School Students (Grades 9,10,11,12) |
| School Name | Mountain View High School |
| Session | Fall 2017 |