| Explore | From our experiences outside of school, we know that plants are mostly green and most do not eat other living things to survive. In class we discovered that plants go thought the process of photosynthesis to create glucose or sugar that they then consume and create energy through the process cellular respiration. Also, we learned that the reactants for photosynthesis are the products of respiration and the products of photosynthesis are the reactants for respiration; it is essentially a cycle. A question that interests us about plants is "What adaptations do plants go through when the ecosystem they are living in, changes?" |
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| Research Question | What temperature of water produces the highest rate of photosynthesis in a plant? |
| Predictions | We believe that the warm/hot will have the highest rate of photosynthesis because the faster moving molecules in the water may have a good effect on the plant's photosynthesis rate. |
| Experimental Design | Materials: 2 beakers (for each temperature), 18 drops of Distilled soap, 30 grams of baking soda, 10 Spinach leaves, 1 Hand held hole puncher, 1 bottle of Distilled water, 2 syringes, 1 disposable pipette, 1 paint brush, 1.5 tray of ice, 1 Hot water bath, 1 Thermometer, 1 Water Tray, 1 Lamp Light, | Procedure: Collect all of the materials listed in the materials list for the experiment. Fill both beakers with about 4 centimeters of distilled water each. Measure out 5 grams of baking soda per beaker filled and pour 5 grams of baking soda into each beaker . Stir the baking soda in the beaker until it is fully dissolved. With the disposable pipette squeeze about 3 drops of soap into each beaker and mix the solutions Once the solutions are done use the hole puncher to make 24 leaf disks with the spinach leaves. Make sure to avoid making disks on the leaf veins. Put 12 leaf disks into each of the 2 syringes and push the leaf disks to the bottom of the syringe using the paintbrush. After this, push the cap of the syringe down until it is almost touching the leaf disks. Put the syringes into the solutions (One syringe per beaker) and suck water into the syringe until it is about ⅓ filled. Flip the syringes and tap them until all the leaf disks are at the top. Push the cap of the syringe until there is no air left at the top. Place your finger onto the top of the syringe and pull the cap down to the bottom of the syringe. Hold this until all of the leaf disks sink to the bottom when released. Do this with both syringes. Hold the syringe sideways over the beaker, pull out the cap and pour all of the leaf disks into the beaker. Pour one syringe into each beaker. Put both beakers under the light and start a timer. At the 0, 5, 10 and 15 minute mark record the temperature of the water and how many leaf disks are floating. Pour the leaf disks and solutions out of the beakers and clean and dry the beakers and syringes. Repeat steps 1-5. Pour about 1.5 inches of water into a hot water bath. Allow this water to heat up to about 45°C Once the water is the correct temperature put the beakers with the solutions into the hot water bath. Allow the solutions to raise to about 40°C. Repeat steps 6-11. Put the hot water bath with the two beakers in it under the lamp light and start a timer. At the 0, 5, 10 and 15 minute mark record the temperature of the water and how many leaf disks are floating. Make sure the temperature of the solution is around 40-44°C during the experiment. If the temperature gets too high turn off the hot water bath, take hot water out of the tub and pour cold water into the tub, not the beakers. Repeat step 13 Repeat steps 1-5 Fill a water tray with about 1.5 inches of water. Pour a tray of ice into the water tray and let it sit until the water is around 7°C. Once the water is the correct temperature put the beakers with the solutions into the water tray. Allow the solutions to cool down to about 9°C. Repeat steps 6-11. Put the water tray with the two beakers in it under the lamp light and start a timer. At the 0, 5, 10 and 15 minute mark record the temperature of the water and how many leaf disks are floating. Make sure the temperature of the solution is around 7-10°C during the experiment. If the temperature gets too high put more ice into the tray. If the temperature gets too low take cold water out of the tray and pour room temperature water into the tray, not the beakers. Repeat step 13. | Independent Variable: Water Temperature Dependent Variable: Number of leaf disks floating Experimental Constants: Water Solution Control: Room Temperature Water |
| Conclusion | The room temperature water will have the best rate of photosynthesis, according to the data. There could easily have been human error occurring during the testing, hence why more trials would possibly bring more accurate data. As thought however, the cooler temperature did not have a good rate of photosynthesis production at about 7°C. The hypothesis formed was incorrect, but if there had more trials which would bring about less human error, there might be a chance that the end results might change in favor of a warmer water temperature. If this experiment was ran a second time it is believed that the number of trials run should stay the same, but instead of running them at the same time, it would be run 1 at a time. The result of this change would be less human error and more focus and care would be able to be put into each trial. The temperature of the hot/warm water might also be changed too. The hot water was on the border of a temperature that kills plant enzymes, and if the hot water was cooled down around 5°C then the results may have changed. Other Questions formed in our project include: “Does a glass beaker change the results from what would have happened in a plastic cup?”and “Were our hot and cold temperature too extreme?” |
| Investigation Theme | POS |
| Grade Level | High School Students (Grades 9,10,11,12) |
| School Name | Fair Lawn high school |
| Session | Fall 2017 |