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Materials and Methods
Procedure is found on pages 258 to 259 in Biology I: Molecular and Cells Laboratory Manual (Dalton, 2012).
Results
"1" represents the first trial, with an average time-to-surface of 282.4 seconds at a distance of seven centimeters from the light source.
"2" represents the second trial, with an average time-to-surface of 422.9 seconds at a distance of four centimeters from the light source.
Conclusion
An autotroph is an organism that uses sunlight and/or other inorganic features of its environment to create/convert the energy it needs in order to survive, such as most plants including the spinach that was used in this experiment (Kent, 2000; Dalton, 2012). A heterotroph, on the other hand, is an organism that needs to consume other organisms in order to meet its internal energy needs; humans are one obvious example of autotrophs, as is almost every member (perhaps every member) of the animal kingdom (Kent, 2000; Dalton, 2012). In autotrophs that photosynthesize, such as the spinach used in the experiment, the photosynthesis occurs in spherical cytoplasmic organelles called chloroplasts located in the cells of the plant an typically especially abundant in the leaves -- broad, flat structures meant to catch a great deal (proportionally speaking) of sunlight (Kent, 2000; Dalton, 2012). The general reaction that occurs in photosynthesis is the taking in of sunlight, which is converted into chemical energy and is used -- along with the raw materials of six...
When the leaf segments have become buoyant enough to rise to the top of the solution, enough oxygen has been produced by photosynthesis to yield this observable result (Dalton, 2012). The overall results of the experiment clearly show that the hypothesis was incorrect, as moving the spinach leaf segments closer to the light source did not only fail to increase the rate of photosynthesis, but actually appeared to significantly decrease the rate of this reaction. The controls on this experiment were not stringent enough to make this statement with true certainty, however; it is possible that increased heat slowed the reactions or affected the density of the solution. Further experimentation with more controlled temperatures is called for.
References
Dalton, K. (2012). Biology I Molecular and Cells: Lecture Guide and Laboratory Manual 3rd Edition. Virginia Beach, VA: Academx Publishing Services, Inc.
Kent, M. (2000). Advanced Biology. New York: Oxford University Press.
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5%. Symptoms were prevelent enough to require the same kinds of injections one would get in high mountain climbing. The CO2, however, fluctuated daily probably because of a different manner in which drawdown during sunlight interacted with night respiration. The crew had to constantly monitor and tweak these levels, often by manipulating irrigation, cutting and storing biomass, and increasing or decreasing photosynthesis. Some thought that this unplanned fuxuation came about
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