Abstract
Revised by Steve Hartter

     This experiment explores two color morphs of the water plant Nymphaea Lotus, the Red Tiger Lotus and Green Tiger Lotus (British Livebearer Association).  Since both plants possess different colors, we sought to find if the red version of the plant photosynthesizes less than the green version of the plant.  The second question explored the difference in carbohydrates, sugars, and enzymes present in the plants.
     Several methods were used to test for sugars, the presence of photosynthetic pigments and enzyme characteristics.  The first series of tests explored the presence of different types of sugars in the plants.  The series of photosynthesis tests which included action spectrum, absorption spectrum, and paper chromatography explored the fundamental differences in light absorption capabilities and their rate of photosynthesis.  The third series of tests tested for the presence of PPO, further helping us discover the fundamental differences in the two different color morphs.
     For all the carbohydrate tests, with the exception of Barfoed’s test, our findings suggested that both plants contained the same carbohydrates.  PPO was absent in both plants.  In the Action Spectrum test results showed that the Green Tiger Lotus photosynthesis more.  These differences were seen in the paper chromatography as well.
    Overall, differences in the Green and Red Tiger lotus were observed, stemming from the different production and frequency of chemicals and different rate of photosynthesis.  Our hypothesis, which states that more photosynthesis occurs in the green plant due to its difference in absorption capabilities, tested accurate.
 
 

Discussion
Revised by Maggie Ornazian

     Our research sought after discovering whether the Red and Green Tiger Lotus photosynthesize differently and if they have differences in their carbohydrate and enzyme structures.  We hypothesized that the different colored pigments of the leaves would lead to different abilities in color absorption and therefore differences in photosynthesis capabilities.  The Green Tiger Lotus reflects green light and absorbs the other colors, which is why we see the green in the plant, because green is the color that is not being absorbed.  Because the green plant can absorb both blue and red light, we predicted that the green plant would be able to photosynthesize more than the red plant.  The differences in their photosynthesis would also lead to differences in their carbohydrate structures.  The results of our experiment confirmed that the Red Tiger Lotus had different carbohydrate characteristics than the Green Tiger Lotus.  This was deduced from the results of Barfoed’s test, the Red Tiger Lotus showed to be made of a simple sugar while the Green Tiger Lotus obtained a complex sugar structure.  This supported our hypothesis, in the aspect of each plant containing different carbohydrate structures.  The spectrum test verified that both plants absorbed different pigments more effectively and also that the green plant photosynthesized more than the red.  These series of test verified a correlation between leaf color and chlorophyll produced.  Our null hypothesis has been negated through analysis of the results.  There was a correlation between the color of the leaves and the presence and amount of chemicals found in photosynthesis.  Paper chromatography was used to identify the pigments which absorb and transmit light.  We hoped that this test would support our hypothesis but the results were inconclusive.  The enzymes we were testing for did not show up in either plant, further research was done to find a working enzyme in both plants.  This data showed no correlation between the color of the leaves and the amount of enzyme consumption, but did shoe that there is indeed working enzymes in aquatic plants.
     We performed the absorption spectrum to verify which wavelengths of light the two plants absorbed the greatest.   Once we have found what light is absorbed, we can find out what is reflected and/or transmitted by the different pigments.  For the Red Tiger Lotus, the peak of the graph (the lowest point) existed at 415 nm, with 0.190 absorbency. The test verified its greatest absorbency at the blue end of the spectrum and reflects the red color for the naked human eye to see.  For the Green Tiger Lotus, the peak was at 590 nm, with a 0.200 absorbency.  This shows that the Green Tiger Lotus absorbs orange light the best and reflects the color green for the naked human eye to see.  This helped to explain why we see different colors in the two plants, but did not really help in the aspect of photosynthetic properties so we turned to another spectrum experiment.
     The action spectrum was our greatest tool in displaying how much photosynthesis is actually going on in both plants.  A blue solution, indophenol was used for each concentration of the Green and Red Tiger Lotus.  The indophenol when added turned the concentrations clear, this was done by the indophenol taking the electrons from the NADP+ reductase.  Indophenol can do that because it has a higher affinity for electrons.  White light has the most photosynthesis with the least absorption, while no light has the least photosynthesis with the highest absorption. We carried out the procedure twice for both plants. The first trial for the Red Tiger Lotus showed absorbencies for no light, blue, red, and white at 0.820, 0.754, 0.623, and 0.592, respectively. The second trial showed 0.815, 0.744, 0.631, and 0.589 in the same order. The first trial for the Green Tiger Lotus resulted in absorbencies at 0.590, 0.571, 0.501, and 0.458. In the second trial we saw absorbencies at 0.587, 0.569, 0.497, and 0.459.  The clearer the liquid becomes, the more photosynthesis is going on.  Since the absorbencies were the lowest in the Green Tiger Lotus, the test results concluded that the Green Tiger Lotus photosynthesized the most.  The action spectrum results supported our hypothesis that the green plant would photosynthesize the most.
    The first of our experiments performed tested for the presence and nature of carbohydrates.    Starch was not found in either plant indicated by the lack of color change during the iodine test.  We preformed Benedict’s test for determining if the carbohydrate is an aldehyde or a ketone.  Both the green and red tiger lotus tested negative which classifies them as ketones.  Bial’s test indicates whether there is a presence of Pherenosis.  In testing for pherenosis, which is a sugar, we found that that neither plant displayed a color change.  This indicates both plants as being pyranose rings.   Barfoed’s test looks for reducing sugars that are monosaccharide.  The Red Tiger Lotus showed positive results of a monosaccharide due to its formation of a brown precipitate during the experiment.  The Green Tiger Lotus formed a precipitate; however, it took longer than that of the Red Tiger Lotus showing positive results of either a disaccharide or polysaccharide.  The Selivanoff’s test verified that both were aldose.  The vial turned red after a minute.  (Malezewski, et al. 2003)  From these test results it was shown that the different plant colors had different carbohydrate characteristics and structures.
     Paper chromatography shows us which pigments the plant absorbs.  For the paper chromatography test, we ran two trials. The results proved to be inconclusive and did not show any pigments.  Although our data did not show this, research has been done to show that all four pigments chlorophyll a and b, carotene, and xanthophylls are absorbed more by green plants (Burger).  This supports our hypothesis which correlates the color of the plant to the amount of photosynthesis that takes place.
     To help further our knowledge of the differences of the two plants we tested for PPO.  Both showed no color change, which verifies that no PPO is present.  The Red and Green Tiger Lotus are under water plants and therefore were figured to test negative for PPO.   Due to the unavailability of tools in the lab we were not able to test for other enzymes but Conrad E. Wickstrom and Julie L. Corkran did.  By using the acetylene reduction technique they found that epiphyte nitrogenase activity was higher in a lake then that of an estuary for the Nymphaea family.  This was due to the high inorganic concentrations of nitrogen in the estuary (Wickstrom).  The Red and Green Tiger Lotus flourish in freshwater which also may have been a factor.   Nitrogenase is an enzyme that catalyzes nitrogen and hydrogen into ammonia (http://www.rcsb.org/pdbmolecules.html).  Although we did not find an enzyme in our experiment there are indeed enzymes in both the Green and Red Tiger Lotus, nitrogenase is just one enzyme that inhibits growth.
    There were a few areas of our experiment that could have produced error. The solution could have been too weak to test positive in some of the tests.  It is possible that because the solutions were weaker then the control’s, that the color-change was so slight that it was unnoticeable to the eye.  More accurate and sensitive tests would have given superior results, and differences in the two plants may have been more noticeable.    Moreover, our tests were done with hand held measuring systems.  These handheld measuring devices were operated by people, which pose inherent problems in accuracy.  There were, also, problems in the accuracy of having equipment that only read to the 4th decimal.
    The experiment went as planned and our null hypothesis was verified incorrect. The experiment resulted in a correlation between plant color and amount of photosynthesis.  Several methods were used to detect presence and amount of sugars in each plant.  The tests for the presence of sugars that were used were Benedict’s, Barfoed’s, Selivanoff’s, and Bial’s.  The photosynthesis lab showed that the different colored plants absorbed different pigments more effectively than others and also that the green tiger lotus was able to photosynthesize more than the red.