| Explore | From our experiences outside of school we know plants are green because their cells contain chloroplasts. We also know plants go through photosynthesis and need nutrients, water and sunlight to survive. In class we discovered the inputs and outputs of photosynthesis which include (Inputs) carbon dioxide, water, energy (From Sun), water (Outputs) oxygen, water, carbohydrates (Sugars). We learned that blue light is absorbed the most by the spinach disks and absorbed the least in green light because the spinach disks reflect the green light. Clear light has a medium absorption rate because the spinach leaf disks will be receiving an equal amount of every color. Some questions that interest us about plants might be How do plants get a waxy coating? Does human touch have an effect on plants? and lastly How do plants adsorb light? |
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| Research Question | We want to study how the colors e,g, green, blue, and clear how they will affect a plant. We came up with our question because we were interested in the different absorption rates of light. This question fits what we know about the topic because when chlorophyll absorbs light, a lot of the energy is transferred directly to electrons in the chlorophyll molecule, raising the energy levels of these electrons. These high-energy electrons make photosynthesis work, and light and chlorophyll are required in the process. |
| Predictions | The cup with the blue light will absorb the the most energy, for light is a form of energy and its absorbed for photosynthesis. The blue light will absorb the most energy out of the three cups. |
| Experimental Design | Our plan was to test how spinach leaf disks perform photosynthesis under different lights such as green clear and blue. Our materials was blue sulfane, representing blue light, green sulfane, representing green light, and clear sulfane, representing clear light. We used soap, 3 cups, 2 cm of distilled water baking soda solution, 36 spinach leaf disks, and a syringe. We filled 3 cups with 2 cm of baking soda solution, and places them to the side. We vacuumed the spinach disks by putting 12 in a syringe and filling it with baking soda solution, put our thumb over the top of the syringe so no air got in, pulled back on the handle, and them let go. This will remove all oxygen from the disks. We did this to all 36 disks and put 12 in each cup, covered the cups, one green, one blue, one clear, and put them under a light at 18 inches away from the cups. We set a timer and checked on the cups every 2 minutes and recorded how many were floating each time we checked. We recorded our data on a data table, recording leaves floating and not floating in each cup. We will observe which color makes the spinach disks perform photosynthesis the fastest. We measured how fast the spinach disks would perform photosynthesis under different colors of light. We will keep the cups, baking soda solution, amount of time, amount of soap, the amount of leaves placed in each cup, the light intensity on each cup, and how we vacuum the air out of the disks. The amount of spinach leaves floating, and the different colored cups would not remain constant because it is what we are testing. |
| Conclusion | The claim we can make for our experiment is that the color of light can determine the rate of which photosynthesis will occur.Possible explanations for our results are that chlorophyll absorbs light very well in the blue-violet and red regions of the visible spectrum. However, chlorophyll does not absorb light well in the green region of the spectrum. The data we collected exemplified how blue light is absorbed faster, causing the rate of photosynthesis to occur quicker, and that green light is not absorbed well, causing the rate of photosynthesis to occur slowly. Clear light had a medium absorption rate because the clear contained all colors of light. Future experiments that could be done to expand on the results of this experiment could be changing the distance of light on the cups, enlarging the leaf disks being photosynthesizing, and using different more of one chemical to see the rate of results. |
| Investigation Theme | POS |
| Grade Level | High School Students (Grades 9,10,11,12) |
| School Name | Arthur L. Johnson High School |
| Session | Fall 2017 |