Carmen Tran
University of California, Fullerton
December 10, 2016
Abstract The purpose of this experiment was to conclude whether C3 or C4 plants had better photosynthetic productivity. The two plants that were used were a C3 plant, a sunflower, and a C4 plant, a sorghum. The prediction for this experiment was that the sorghum would have a greater photosynthetic rate. To perform the experiment, a Qubit system was used to measure the concentration of carbon dioxide (CO2) in a bag. The amount of CO2 used by the plant was determined by subtracting the final CO2 concentration by the initial CO2 concentration. Various levels of irradiance were used to measure the plant’s photosynthetic rate. Each plant went through two trials with the level of irradiance at 100%, 75%, 50%, 25%, and 0%. After collecting all the data, the results showed that the sunflower had a much higher photosynthetic rate than the sorghum. The hypothesis was refuted because the C3 plant had a greater photosynthetic productivity than the C4 plant. Possible reasons for this outcome could be that the fluctuating light and temperature made photosynthesis less efficient for C4 plants …show more content…
The evolution of oxygenic photosynthesis in cyanobacteria was responsible for the oxygen-rich atmosphere leading to the great evolutionary success of plants in which they continued to provide the oxygen for all other organisms on Earth (Freeman, et al., 2014). Plants became the backbone for sustaining all life on