Photosynthesis Plant Disc Lab
Laboratory 8, AP Biology
Abstract. In this lab, photosynthetic rate was examined using small discs of plant leaves as a model. The photosynthetic rate was examined by using light, heat, and radiation as variables. The photosynthetic rate was greatest when placed in a microwave. The data almost concurs with how photosynthesis was expected to unfold, but not 100%. The data below expresses the lab to its full extent (Chowdhury, Fox, Paneet 2015) (Rodriguez [Associating] 2015).
Introduction
In this lab, we explored the rate of photosynthesis using discs of plant leaves from the garden as the model plant. Photosynthetic rate is the amount of photosynthesis taking place over time. Photosynthesis is the process of plants taking in CO2, water, and light to create usable energy for the plant. Light stimulates the chloroplasts to undergo the Calvin Cycle which converts the CO2 and water into glucose and oxygen which is release from the cell (Reece 2015). The equation is as follows:
Sunlight + 6CO2 + 6H2O ------> C6H12O6 + 6O2 (MSU, retrieved 2015)
The main objective of this lab was to determine the effects of different variables on the rate of photosynthesis. Plant discs were placed in a cup of solution (NaHCO3 and H2O, the source of reactants) in several different conditions. 10 plant discs were placed in each of 3 separate cups. One was placed directly under a lamp, providing heat and light. One was placed in a microwave, providing heat and light as well as exposure to radiation. One was simply placed on the countertop as a control group (Rodriguez [Associating] 2015) (Figures 1-12).
We hypothesized that the plant discs below the lamp would photosynthesize the quickest. Knowing that light simulates photosynthesis, it seemed the most logical for these plants to have the highest photosynthetic rate.
Methods
In this lab, given to us by Ms. Rodriguez, we were to determine the effects of different variables on the rate of photosynthesis. First, we cut out 10 discs out of a small leaf and put them in a syringe with about 5 mL of NaHCO3. We repeated this process for 3 syringes. After this, we drew out the gas from the leaf structure by creating a vacuum in the syringe by repeating a back and forth motion with the plunger. Once the leaves had no gas remaining (shown by a sinking of leaves), we transferred them into a 3 large cups with 150 mL of the solution each. We then selected which cups would be which variables. The first cup would be our control, and thus would receive no light and no assistance whatsoever. The second cup would be placed under a lamp, thus receiving light energy as a sole source. The third cup would be placed in a microwave for 1 minute and 30 seconds, letting a decent amount of radiation and heat energy pass into the leaves . We would check the leaves every minute (for 3 minutes) to track their position, and thus their photosynthetic rate within the cup (Rodriguez [Associating] 2015) (Figures 1, 2).
Results
Our results yielded little promise for quick photosynthetic processes. Our first cup, the control, yielded no results. No leaves had moved during the time we watched. In our second cup, the light only cup, we yielded no results. The leaves had once again not moved in the 7 minutes we took to check and track. Our third cup, however, was found with floating leaves abundant. The leaves had indeed used some of the radiation or heat energy to photosynthesize extremely quickly and almost instantaneously float to the surface of the solution. This method proved too quick to measure (Chowdhury, Fox, Paneet 2015) (Figures 3-12).
Discussion
Our experiment procedure was unusual and unique as it did yield some flaws and errors. As mentioned before, we used a microwave to stimulate the photosynthesis process in our leaf disks, the use of the microwave as unique as it was did result in failure because of the ability to not accurately measure the progress of the leafs floating up due to how rapidly they rose and the evaporation or loss of some the liquid solution (NaHCO3). In addition, the movement and progress we saw in our other cups with the leaves was hardly significant and rather unmeasurable. Finally, taking into account human error, there could have been an infinite amount of things we did wrong that gave us the results we have, such as cell destruction during the vacuum step or not enough time allotted for leaf stimulation.
Conclusion
Our initial hypothesis that the leaves under the direct influence of the light lamp would photosynthesize the quickest or provide the most change was incorrect. Instead we found most change in the cup that was placed in the microwave for 90 seconds (or 1 minute and 30 seconds). The reason for might have been because of the high and constant source of light and heat to the leaves, as well as the radiation that the microwave emits. If we redid this experiment differently, we could have altered the time we took to gather our data and leave our cups containing leaves out for a longer amount of time so that there could have been a noticeable and measurable change in the leaves. In conclusion, the microwaved sample yielded the best results.
Citations
Chowdhury, Fox, Paneet (2015). Photosynthetic Rates Lab Results. Coppell.
Reece, J. B. (2015). Campbell Biology: Concepts & Connections (Vol. 8). Upper Saddle River, New Jersey: Pearson Education.
Rodriguez (2015) (Associating). Photosynthetic Rate Lab. Coppell.
The Chemical Equation of Photosynthesis. (n.d.). Retrieved April 8, 2015, from https://www.msu.edu/user/morleyti/sun/Biology/photochem.html
Laboratory 8, AP Biology
Abstract. In this lab, photosynthetic rate was examined using small discs of plant leaves as a model. The photosynthetic rate was examined by using light, heat, and radiation as variables. The photosynthetic rate was greatest when placed in a microwave. The data almost concurs with how photosynthesis was expected to unfold, but not 100%. The data below expresses the lab to its full extent (Chowdhury, Fox, Paneet 2015) (Rodriguez [Associating] 2015).
Introduction
In this lab, we explored the rate of photosynthesis using discs of plant leaves from the garden as the model plant. Photosynthetic rate is the amount of photosynthesis taking place over time. Photosynthesis is the process of plants taking in CO2, water, and light to create usable energy for the plant. Light stimulates the chloroplasts to undergo the Calvin Cycle which converts the CO2 and water into glucose and oxygen which is release from the cell (Reece 2015). The equation is as follows:
Sunlight + 6CO2 + 6H2O ------> C6H12O6 + 6O2 (MSU, retrieved 2015)
The main objective of this lab was to determine the effects of different variables on the rate of photosynthesis. Plant discs were placed in a cup of solution (NaHCO3 and H2O, the source of reactants) in several different conditions. 10 plant discs were placed in each of 3 separate cups. One was placed directly under a lamp, providing heat and light. One was placed in a microwave, providing heat and light as well as exposure to radiation. One was simply placed on the countertop as a control group (Rodriguez [Associating] 2015) (Figures 1-12).
We hypothesized that the plant discs below the lamp would photosynthesize the quickest. Knowing that light simulates photosynthesis, it seemed the most logical for these plants to have the highest photosynthetic rate.
Methods
In this lab, given to us by Ms. Rodriguez, we were to determine the effects of different variables on the rate of photosynthesis. First, we cut out 10 discs out of a small leaf and put them in a syringe with about 5 mL of NaHCO3. We repeated this process for 3 syringes. After this, we drew out the gas from the leaf structure by creating a vacuum in the syringe by repeating a back and forth motion with the plunger. Once the leaves had no gas remaining (shown by a sinking of leaves), we transferred them into a 3 large cups with 150 mL of the solution each. We then selected which cups would be which variables. The first cup would be our control, and thus would receive no light and no assistance whatsoever. The second cup would be placed under a lamp, thus receiving light energy as a sole source. The third cup would be placed in a microwave for 1 minute and 30 seconds, letting a decent amount of radiation and heat energy pass into the leaves . We would check the leaves every minute (for 3 minutes) to track their position, and thus their photosynthetic rate within the cup (Rodriguez [Associating] 2015) (Figures 1, 2).
Results
Our results yielded little promise for quick photosynthetic processes. Our first cup, the control, yielded no results. No leaves had moved during the time we watched. In our second cup, the light only cup, we yielded no results. The leaves had once again not moved in the 7 minutes we took to check and track. Our third cup, however, was found with floating leaves abundant. The leaves had indeed used some of the radiation or heat energy to photosynthesize extremely quickly and almost instantaneously float to the surface of the solution. This method proved too quick to measure (Chowdhury, Fox, Paneet 2015) (Figures 3-12).
Discussion
Our experiment procedure was unusual and unique as it did yield some flaws and errors. As mentioned before, we used a microwave to stimulate the photosynthesis process in our leaf disks, the use of the microwave as unique as it was did result in failure because of the ability to not accurately measure the progress of the leafs floating up due to how rapidly they rose and the evaporation or loss of some the liquid solution (NaHCO3). In addition, the movement and progress we saw in our other cups with the leaves was hardly significant and rather unmeasurable. Finally, taking into account human error, there could have been an infinite amount of things we did wrong that gave us the results we have, such as cell destruction during the vacuum step or not enough time allotted for leaf stimulation.
Conclusion
Our initial hypothesis that the leaves under the direct influence of the light lamp would photosynthesize the quickest or provide the most change was incorrect. Instead we found most change in the cup that was placed in the microwave for 90 seconds (or 1 minute and 30 seconds). The reason for might have been because of the high and constant source of light and heat to the leaves, as well as the radiation that the microwave emits. If we redid this experiment differently, we could have altered the time we took to gather our data and leave our cups containing leaves out for a longer amount of time so that there could have been a noticeable and measurable change in the leaves. In conclusion, the microwaved sample yielded the best results.
Citations
Chowdhury, Fox, Paneet (2015). Photosynthetic Rates Lab Results. Coppell.
Reece, J. B. (2015). Campbell Biology: Concepts & Connections (Vol. 8). Upper Saddle River, New Jersey: Pearson Education.
Rodriguez (2015) (Associating). Photosynthetic Rate Lab. Coppell.
The Chemical Equation of Photosynthesis. (n.d.). Retrieved April 8, 2015, from https://www.msu.edu/user/morleyti/sun/Biology/photochem.html