1. Music’s Effect on Photosynthesis Introduction Photosynthesis consists of two different reactions: light independent and light dependent. Both reactions occur mainly in the mesophyllic cells of leaves. Photosystems on the membrane of a thylakoid (photosynthetic organelle) use sunlight to excite electrons and split water. The excited electrons continue through the electron transport chain, and produce NADPH and ATP, while the hydrogen ions from the water themselves power ATP synthase, producing more ATP, while the oxygen leaves as a byproduct. This NADPH and ATP enters the Calvin cycle, where CO2 from the atmosphere is used in a series of reactions to produce 3-carbon organic molecules used to create sugars such as glucose and sucrose. The other byproduct of these reactions, hydrogen ions, are pumped back into the thylakoids for future ATP synthase reactions. The purpose of this experiment was to test if sound waves produced by various styles of music would have an effect on the rate of photosynthesis, which could be measured by the amount of time it took for leaf disks that had the air removed from them rise to the surface of a baking soda-water solution. If the rate of photosynthesis is related to the genre of music, then quicker/ louder styles of music will result in a quicker Rate of photosynthesis. Question and Hypothesis Do different genres of music, and their resulting different decibel level, affect the rate of photosynthesis? If the rate of photosynthesis is affected by different decibel level of music, than a higher decibel level will result in faster photosynthesis. Experiment Design Begin by punching out 15 leaf disks from a piece of spinach using a hole punch. Then, create a 1.5% solution of baking soda to water, in a 200 mL beaker. Prepare a stopwatch, and surround beaker with headphones. Connect headphones to music player. Remove 15 mL of water using a syringe, and remove the plunger from the syringe. Insert 3 leaf disks into the water filled syringe, and reinsert the plunger. Remove excess air from the syringe, and then plug the open end of the syringe. Draw back the plunger, making sure that the end is stoppered, and keep it pulled back while shaking the syringe. Release the plunger, remove hand from the nozzle, and continue to shake the syringe. If done correctly, all leaf disks should eventually fall to the bottom of the syringe. Remove plunger from syringe again, and pour water with leaf disks into beaker. As the leaf disks enter the water, begin the stopwatch. Play no music while performing the experiment, as this will be the control group. Take a lap on the stopwatch once each disk reaches the top of the beaker. Divide the distance from the bottom to the top of the beaker, by the average time the disks took to rise. This is the disk speed. Perform the experiment four more times, each with the different type of music playing through the headphones. Materials Spinach leaves Hole punch 200 mL Beaker Syringe Headphones Stopwatch Song: Number of the Beast by Iron Maiden Song: Temple of Time Dubstep Remix by Arödnak Song: Veni Veni Bella by The Medieval Baebes Song: Nobody Knows the Trouble I’ve Seen by Louis Armstrong Results Decibel level: dubstep-80 celtic-70 jazz-65 metal-75 control-55 Speed of photosynthesis (rise speed): dubstep-.04 cm/s celtic-.03 cm/s jazz--.01 cm/s metal-.04 cm/s control-.03 cm/s Conclusion The hypothesis stating that quicker and heavier music would result in a faster rate of photosynthesis was supported to a certain degree. The experiment involved removing oxygen from leaf disks and placing them in a solution with music waves playing through it and timing their rise. We recorded the time it took for the disks to begin to rise and then reach the top. From there, we found average times for each genre and the average speed. We then compared this data to the bpm and decibel levels of each genre and graphed it. Errors may have been found in the expired baking soda and varied decibel levels that oscillated rapidly. Imrpoving the experiment could be done by replacing the baking soda and also testing the music to find closer decibels. The results of the experiment show a loose relationship between the music and photosynthesis. For example, the very soft jazz had the slowest average time and dubstep, the fastest and loudest genre, had the quickest time, tied wit the loud metal. However, having the multiple variables lessened the reliability of the experiment. Testing the variables separately would be more veneficial. Overall, the results of the experiment are rather inconclusive