The Effect of Light Intensity on Spinach Leaf Disks
We monitored the effect of light intensity (lamp) and measured the rate of photosynthesis in spinach leaf disks. The question we want to answer is: how does light intensity affect the rate of photosynthesis in leaf disks? Our independent variable is: the distance from the light (intensity). Our dependent variable is: the amount of time it took for the disks to float. Our control is the syringe covered in aluminum foil. Our constants were the same syringes, straws, spinach plants, and the same solution.
At first we prepared 3 syringes, two for ...view middle of the document...
We then prepared the two experimental syringes, one close to the light and one away, with the tips up in front of the light and one 25cm away and one 50cm away from the lamp.
My hypothesis was: if we add light to the plant disks the disk will float because plants absorb light to produce oxygen. I support my hypothesis because I know that plants absorb light energy because they have a light absorbing pigment that is found in the cells of green plants called chlorophyll. So if there is a source of light energy a plant will use photosynthesis to create oxygen causing the disks to float.
In our observations we saw that the syringe closest to the light had produced oxygen faster and had more floating disks then the other syringe which had produced oxygen but slower and had less floating disks because the more the leaf disks are closer to the light source the more intense the wave energy is going to be.
In conclusion from this experiment we learned that the leaves of the plants contain chlorophyll which absorbs light energy and is where carbon dioxide enters then oxygen escapes this process is called photosynthesis. When photosynthesis occurs oxygen is produced and re-fills the air spaces that caused the leaf disks to float. Some sources of error in this experiment are: the same kind of plant, solution, syringes, foil, light, lamp, straws, and distance the syringe is from light. All and all this experiment was a success and my hypothesis was correct. We seen the process of photosynthesis and seen that the syringe closest to the light (25cm) had the most floating disks. Then it was syringe 2 that was in the middle (50) and syringe 3 which was the control and had no floating disks.