Photosynthesis Essay

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The process of photosynthesis is present in both prokaryotic and eukaryotic cells and is the process in which cells transform energy in the form of light from the sun into chemical energy in the form of organic compounds and gaseous oxygen (See Equation Below). In photosynthesis, water is oxidized to gaseous oxygen and carbon dioxide is reduced to glucose. Furthermore, photosynthesis is an anabolic process, or in other words is a metabolism that is associated with the construction of large molecules such as glucose. The process of photosynthesis occurs in two steps: light reactions and the Calvin cycle. The light reactions of photosynthesis take place in the thylakoid membrane and use the energy from the sun to produce ATP and NADPH2. The Calvin cycle takes place in the stroma of the chloroplast and consumes ATP and NADPH2 to reduce carbon dioxide to a sugar. Light Energy + 6 H2O + 6 CO2  C6H12O6 + 6 O2 In this laboratory experiment, the rate of photosynthesis was measured through the use of the “floating leaf disk technique.” The leaf disks were placed into a syringe and the O2 and CO2 in the mesophyll layers of the leaves were removed and then replaced with sodium bicarbonate or water, causing the leaves to sink to the bottom of the container. If one determines the number of leaf disks rising to the top as a result of an increase in oxygen gas in the mesophyll cells, then the rate of photosynthesis is able to be measured because O2 is a product of photosynthesis. The first step of this experiment was a feasibility study of the variance in the photosynthetic activity of the leaf disks in both water and bicarbonate solutions. After five minutes of light exposure, all of the leaf disks in the bicarbonate solution (10 disks) had ... ... middle of paper ... ...d have led to inaccurate measurements because the leaves would not have been able to perform photosynthesis and rise to the surface. In addition, the air in the mesophyll layers of the leaves may not have been properly cleared by the syringe, which would have made it easier for the leaf disks to float to the surface because the leaf would have to perform a lower rate of photosynthesis. All of these errors may have been prevented by having a partner check over sections of the experiment to ensure accurate results and repeating the experiment numerous times to account for random error. Moreover, a future experiment is to determine the effect that the distance between the lamp and the solution has on the rate of photosynthesis. Several experiments with a similar setup to this experiment that vary the distances between the lamp and solution could be used to test this.

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