It simply used, a test tube, meniscus, and pipette. Then a 15 cm long sprig of elodea was placed in the test tube, after 2 cm was cut from the stem. The test tube was the filled with sodium bicarbonate solution, with 3 cm left at the top of the test tube. The volumeter stopper was then placed in the test tube. The stopper was the adjusted so the solution extended 1 to 2 cm into the pipette. The volumeter test tube apparatus was then left sealed for 10 minutes, in order to allow the Elodea to adjust to the new environment. Next, the measurement of the pipette was taken as the start point. Then a light was placed facing the test tube apparatus. However, a 50 ml beaker of water was placed between the test tube apparatus and light, in order to absorb heat. The preceding steps were repeated two additional times separately, with fresh materials. Then the light was covered with aluminum foil, before being turned on. Therefore, no light from the light source reached the test tube apparatus. After ten, minutes the new measurement of the pipette was taken, to note oxygen released from photosynthesis. This was then repeated separately, under the same conditions. Only the presence of the tin foil was changed, so that white light shined on the test tube. Then the measurement of the pipette was taken after 10 minutes of white light. Lastly, a green plastic film was placed on the light, so the green light shined on the test …show more content…
The highest amount of oxygen was released from the Elodea receiving no light, rather than the least. The other aspect of the hypothesis was supported because more oxygen was released from the elodea which received white light than green light. Some issue likely occurred with the elodea receiving no light. Several things may have contributed to the odd no light results. For example, inaccurate measurements may have been taken. Also, perhaps, the Elodea were slightly different, which contributed to different rates of photosynthesis. The experiment suggests that white light frequencies result in higher rates of photosynthesis than green light. This seems to fit with scientific knowledge, because chloroplast appear greens so therefore reflect some green light frequencies. However, the lab results are questionable because the highest rate of photosynthesis occurred under no light. But, light is the source of energy in photosynthesis. So the results of the lab are questionable, likely due to mistakes or uncontrolled variables, such as Elodea