Photosynthesis Lab - Hour 6 by Jeremy Mohn https://padlet.com/jmohn/fsvtq886ff0u Group 1 - Light Color en-us 2016-10-15 20:45:31 UTC 2024-04-07 00:29:47 UTC hello@padlet.com http://d20uo2axdbh83k.cloudfront.net/20141020/47034972b1207c3982eed5f412f5322b.gif Results jmohn https://padlet.com/jmohn/fsvtq886ff0u/wish/130936365 The leaf chads under the white light had the highest net rate of photosynthesis with an ET50 value of 173 seconds. The leaf chads under the blue light had the second highest with 360 seconds, then red with 528 seconds and last was green with 1200 seconds. It is important to note that the ET50 of the leaf chads exposed to green light likely would have been higher than 1200 seconds, as the experiment was stopped before ET50 was reached. The rate of photosynthesis was then found by taking the inverse of the ET50 values for each light color. The color with the lowest ET50 value and highest 1/ET50 value, in this case white, has the highest rate of photosynthesis.]]> 2016-10-15 20:45:31 UTC https://padlet.com/jmohn/fsvtq886ff0u/wish/130936365 Conclusion jmohn https://padlet.com/jmohn/fsvtq886ff0u/wish/130936366 The hypothesis was disproved, as white light proved to cause leaf chads to rise the fastest, followed by blue light, red light, and green light, instead of red light, followed by blue, white, and green light, as was the predicted outcome. Through this lab, the researcher can conclude that white light allows for photosynthesis to occur at the fastest rate in plants, specifically baby spinach leaves, as the buoyancy of leaf chads in a sodium bicarbonate solution is directly related to rate of photosynthesis. This is because as the leaf chads photosynthesize, they are filled with oxygen, which makes them more buoyant. White light enabled the greatest rate of photosynthesis possibly because it contains light of all visible colors, and therefore can potentially be almost completely absorbed by the pigments in plants, such as chlorophyll. Blue light enabling a higher rate of photosynthesis than red and green light can be explained simply by observing the action spectrum of plant pigments, which shows blue light being the most absorbed, followed by red and green light. This knowledge can be applied in greenhouses and other plant growing scenarios in order to put plants in environments in which they will have the greatest rate of photosynthesis, and therefore the greatest rate of growth. Some sources of error include the fact that the colored light of the experimental groups was likely at a much lower intensity than that of the white light control. Despite attempts by the researcher to limit this difference in intensity by applying a clear filter to the control group, that likely was not enough to lower the intensity to the extent that it was lowered by the colored filters. This could suggest that white light is not necessarily the best color of light for photosynthesis, but rather that the researcher came to this conclusion through an error in the experimental design. Another source of error could include that the leaf chads were exposed to light and had already begun to photosynthesize before the timer was started. This would cause the recorded ET50 for some of the cups to be less than what it would have been, had the experiment been more controlled in this regard. The researcher was also not successful in controlling the number of leaf chads that sunk the the bottom of the containers, so some containers had all six sink, while other only had two sink, meaning the researcher had to wait for different numbers of leaves to rise to the top of the container. This would alter the consistency and control of the experiment, which would in turn affect the accuracy of the observed rates of photosynthesis. ]]> 2016-10-15 20:45:31 UTC https://padlet.com/jmohn/fsvtq886ff0u/wish/130936366 Procedure jmohn https://padlet.com/jmohn/fsvtq886ff0u/wish/130936367
  • Gather materials. 
  • Prepare a 0.2% sodium bicarbonate solution.
  • Hole-punch 24 leaf chads out of live baby spinach leaves.
  • Place 6 leaf chads in a syringe.
  • Fill the syringe with the sodium bicarbonate solution. 
  • Place thumb over the top of the syringe and pull back on the stopper, creating a vacuum, which will cause the leaf chads to fill with the sodium bicarbonate solution and sink.
  • Fill a plastic cup with 20 mL of sodium bicarbonate solution. 
  • Pour the leaf chads into the cup. Remove any that don't sink (make sure an even number remains).
  • Repeat steps 4-8 four more times with the remaining leaf chads. 
  • Place a red filter over one of the cups, a green over another, a blue filter over another, and a clear filter over the final cup. 
  • Set up a lamp over the cups. 
  • Time how long it takes until half of the chads in each cup float to the top.
  • Record data and compare to find the highest rate of photosynthesis, as the cup with the lowest ET50 had the highest rate.
  • Put away materials, clean up area, and draw conclusions.
    • ]]>     2016-10-15 20:45:31 UTC https://padlet.com/jmohn/fsvtq886ff0u/wish/130936367     Research Question jmohn https://padlet.com/jmohn/fsvtq886ff0u/wish/130936368 Which light color allows for the fastest rate of photosynthesis in baby spinach leaves?]]> 2016-10-15 20:45:31 UTC https://padlet.com/jmohn/fsvtq886ff0u/wish/130936368 Hypothesis/Prediction jmohn https://padlet.com/jmohn/fsvtq886ff0u/wish/130936369 Hypothesis: Red will have the highest rate of photosynthesis, blue will have the second highest, white will have the third highest, and green will have the lowest. 

    Prediction: If red will have the highest rate of photosynthesis, blue will have the second highest, white will have the third highest, and green will have the lowest, then the leaf chads in the solution under the red light will float to the top in the least amount of time, followed by the others in the previous order, as the leaf chads under the red light will produce oxygen via photosynthesis at the fastest rate, making them less dense. 
    ]]>     2016-10-15 20:45:31 UTC https://padlet.com/jmohn/fsvtq886ff0u/wish/130936369     Graph jmohn https://padlet.com/jmohn/fsvtq886ff0u/wish/130936370 2016-10-15 20:45:31 UTC https://padlet.com/jmohn/fsvtq886ff0u/wish/130936370 The Effect of Light Color on the Rate of Photosynthesis in Living Baby Spinach Leaves jmohn https://padlet.com/jmohn/fsvtq886ff0u/wish/131552334 Names: Divya Jain, Lauren Cullen, Mark Doyle, Vinay Pahwa]]> 2016-10-18 16:50:00 UTC https://padlet.com/jmohn/fsvtq886ff0u/wish/131552334