| Explore | We know that plants require sunlight and water to undergo photosynthesis, and we know that different temperatures of water will change the outcome of plant growth. In class, we have discovered that certain plants will also undergo cellular respiration as well as photosynthesis. Some questions could be what exactly happens inside the seed of a plant that causes it go grow? Why do the temperatures of the water affect the outcome of the plant? |
|---|---|
| Research Question | We want to know what temperature is best suited for plant growth stimulation. We came up with the question because we already knew that the amount of light affected the outcome of plant growth, so we wanted to know if the other main variable, water temperature, would affect it as well. This question fits well with our topic because of how both water usage and light usage are the main resources a plant needs to grow, and when we tested one, we were interested in the other. |
| Predictions | We predict that when room temperature water is used for plant growth, then the water will stimulate more plant growth than hot or cold temperatures. We think this will happen because when using extremely hot or extremely cold temperatures, the roots will become even more sensitive and fragile, and it will make it nearly impossible for growth. |
| Experimental Design | 1. Gather materials (spinach, hole puncher, 3 beakers with cold water, lukewarm water, and hot water respectively, sodium bicarbonate, 3 syringes). 2. Obtain 100 mL of cold water and 1 gram of sodium bicarbonate to make your bicarbonate solution and place in a 200mL beaker. 3. Repeat Step 2 for the lukewarm and hot water beakers 4. Hole punch 30 uniform leaf disks (10 for each solution beaker) in texture and thickness avoiding major leaf veins. 5. Remove the plunger of the syringe and place ten leaf disks in the syringe barrel. Do this for two other syringes also. 6. Replace the plunger being careful not to crush the leaf disks. Push on the plunger until only a small volume of air and leaf disk remain in the solution. 7. Draw a small volume of the cold sodium bicarbonate solution in the syringe. Invert the syringe and tap the syringe to suspend the leaf disks in the solution. Repeat this for the lukewarm and hot bicarbonate solutions 8. Push the plungers removing as much air as possible from the syringe. 9. Hold a finger over the syringe opening and draw back on the plunger to create a vacuum. Hold this for 10 seconds while swirling the syringe to further suspend the leaf disks in solution. 10. Let off the vacuum and repeat step 8 if needed 2-3 more times until all leaf disks sink. 11. Pour the disks and solution back into their respective 200mL beakers. 12. Place the three beakers under the ambient light. 13. Record the number of floating disks at the end of each minute on the data table for a total of 10 minutes. QUESTIONS: The variables tested will be the temperature of the water. We will be observing and measuring the amount of plant growth in all three of the plants. The variables kept constant will be the amount of light all the plants are under, the number of leaf chads in the tubes, and the duration of time for everything. Our data will be recorded in a chart, it will be a 3x3 chart because we have the cold temperature, room temperature, and hot temperature. We will be measuring the number of chads that float to the top of the beaker. |
| Conclusion | In conclusion, our experiment showed us that lukewarm water was the best temperature of water for plant growth because it had the most leaf chads to float to the top. Our hypothesis was proven correct because we hypothesized that the lukewarm water would be the best in stimulating photosynthesis because both the extremely hot and cold water would not stimulate as much growth. The enzymes needed for photosynthesis would be killed in the extremely hot temperature and in the extremely cold water, the enzymes are being broken down slowly, which results in slower growth. In our data, the hot water had only 1 leaf chad out of the 10 leaf chad's floating throughout the 10 minute time period. Also, in the cold water 4 leaf chad's floated to the top, which shows that there was photosynthesis happening, but at a slower rate. In the lukewarm water, there was a constant rate of about 1 leaf chad floating per minute and at the end of the 10 minutes, there were 8 floating out of the 10 leaf chads. In the future, we can experiment with using more time to watch the photosynthesis rate of the leaf chads in all of the temperatures of the water. We can also use 2 beakers per temperature to ensure that the photosynthesis rate isn’t based on human error. |
| Investigation Theme | POS |
| Grade Level | High School Students (Grades 9,10,11,12) |
| School Name | Fenton High School |
| Session | Fall 2017 |