IB Bio lab report on photosynthesis Essays

IB Bio lab report on photosynthesis Essays IB Bio lab report on photosynthesis Paper IB Bio lab report on photosynthesis Paper Essay Topic: Synthesis This process takes place in he chloroplasts of plants, which include chlorophyll. Chlorophyll is essential for photosynthesis, since it absorbs the suns light. Green plants then use this light to combine CO and H2O for making sugars and oxygen. After this process Oxygen is being released though pores called stomata. The overall reaction can be expressed as follows; 61420 + CHIC 0 C,H2O, + 6021 There are four variables that affect the rate of photosynthesis; light intensity, temperature, CO and water. 2 However, is it possible to count in the color of light, too, which I am going to investigate in this lab. Since the photosynthesis sakes place in chloroplasts that has chlorophyll, the rate of photosynthesis can be affected by different colors of light, since the absorption of light changes within different colors. Research Question: What color of light is most effective on the rate of photosynthesis? Five different colored transparencies (red, green, yellow, blue, purple) are being used for changing the lights color. Within 5 minutes for each one of them, they will be used in order to see oxygen bubbles rising from a used water plant. The produced oxygen (in the form of bubbles) indicates the rate of photosynthesis ND is being measured by counting bubbles. The highest amount of oxygen bubbles being produced per minute is equivalent to the highest rate of photosynthesis, and the color providing the best circumstances for the production of photosynthesis. Hypothesis: Since Plants absorb green light, I expect the rate of photosynthesis to be the highest when red light is being used. This is due to the color spectrum, where one can say that red is the opposite color to green. Therefore, I expect red light to provide the most energy for the plant absorbing it. Variables: Variable Type Method Light intensity Controlled At the most intense level possible (770 lug) and a distance of CACM from the aquarium. Temperature of water At room temperature; adding colder water when temperature rises. PH level All solution has a pH of 7. Plant type and color Leaves of the same species; green Colored light Independent Changing colors with colored slides (yellow, blue, red, green, purple) in front of the light source. The rate of photosynthesis Dependent Changed by the color of light, collected with stop watch and counted by produced bubbles. Material: 2000 CM of water (-300 for every color + water for controlling variables) One lass/ glass cup One test tube One funnel 2-3 healthy water plants One thermometer Spotlight Five colored transparencies (blue, red, yellow, green, purple) Stopwatch One lug meter Proceed re: Before starting the experiment, the spotlight has to be placed at point on the table, 20 CM away from where the plant is to be set. Then the lug meter is to be taken for calculating the intensity of the spotlight onto the plant. Following this, the color transparencies will be set in front of the light and the resulting light intensity will be noted by placing the lug meter on the place where the plant is to be set. For each run, under-water cut leaves from the water plant are put carefully in the funnel, which small open end is put into the test tube. This all is to be done in the flask filled with the water provided for each run and is to be placed at the distance of 20 CM from the spotlight. 3 The water temperature is to be measured and to be kept constant at all time OIC). The first color transparency is then to be placed in front of the spotlight and the oxygen bubbles rising from the plants leaves are to be counted. After 11/2 minute, the first run of the first color is completed and following 4 runs have o be concluded the same way. In case the water temperature rises, cold water has to be added. The experiment then has to be repeated 4 more times with the different colored transparencies in the same way. (A procedure repeating each run 5 times, would be the best for minimizing errors that could occur, due to the ex. Rule. ) The collected data is noted on paper and will be processed to determine the rate of photosynthesis at every color. Data collection and raw processing: The experiment was carried out with the following order of colors: Run 1-5: Blue Run 6-10: Green Run 11-15: Yellow Run 16-20: Red Run 21-25: Purple Raw Data Qualitative Observations: Run 1-5: A high number of bubbles rose up Run 6-10: Almost no bubbles were being produced Run 11-15: Only a few bubbles rose up Run 16-20: A very large number of bubbles were being produced Run 21-25: Not too many bubbles were being produced by the plant * Until the first bubbles rose up, some time has had passed already; the observations are only being compared with the data processed by the plant being used in this experiment, not with those from others. Quantitative Data: Run Number of Oxygen bubbles being produced with Blue light Number of Oxygen bubbles being produced with Green light Number of Oxygen bubbles being produced with Yellow light Number of Oxygen bubbles being produced with Red light Number of Oxygen bubbles being produced with Purple light Run I(after 90 sec. )4 2 3 Run 2 (after 180 sec. ) 5 11 4 13 Run 3 (after 270 sec. ) 12 15 6 Run 4 (after 360 sec. ) 14 5 Run 5 (after 450 sec. ) For a better overview the diagram below represents the quantitative data provided. Processed Data: The collected data has to be processed. This will be done by calculating the mean values for all runs of each of the colors by using Excel. The results will be put in a table, as well as in a diagram for a better overview. Also, for finding out whether the collected data is reliable or not and how different the results are to the means, the standard deviation for all runs of the colors have to be calculated using the same method. 6 Green Yellow Red Purple Mean 10 2. 6 4. 4 Stand. Deep. . 82 0. 5 0. 96 Table providing the processed data Diagram providing the processed data for a better overview Conclusion After all data has been collected and processed, one can say that the stated hypothesis from the beginning of the lab report, which says that red is the lour that provides the best circumstances for the production of oxygen, is being supported by the observations and calculations made. The qualitative observations showed clearly, that the plant produced most oxygen un der red light. The calculations of the means demonstrated that even though blue and red light had similar effects on the plant, the red light was most effective. Further calculations of the standard deviation showed that the data is not highly spread, standing for valuable data that has been collected. Therefore it is to be concluded that the color providing best light for the production of oxygen and Hereford for the rate of photosynthesis is red, followed by blue. Furthermore, the data collected in this experiment is supported by sources and expectations from the B Biology curriculum (and others), which states conclusions about the color spectrum and the effect on plants absorbing the different wavelengths of colored lights. However, it is to be noted that the data being collected points out some significant differences, as well as similar numbers of oxygen being produced. This is probably due to the small protection of the light coming from the other sides onto the plant, which was not shielded and completely darkened except for the light coming from the spotlight.