Photosynthesis Lab - Hour 3 by Jeremy Mohn https://padlet.com/jmohn/p1xbzdnfhzci Group 3 - Water Temperature en-us 2016-10-15 20:38:52 UTC 2025-09-24 17:12:13 UTC hello@padlet.com http://d20uo2axdbh83k.cloudfront.net/20141020/47034972b1207c3982eed5f412f5322b.gif Graph jmohn https://padlet.com/jmohn/p1xbzdnfhzci/wish/130936100 2016-10-15 20:38:52 UTC https://padlet.com/jmohn/p1xbzdnfhzci/wish/130936100 Hypothesis/Prediction jmohn https://padlet.com/jmohn/p1xbzdnfhzci/wish/130936101 Hypothesis: Hot and cold temperature change will decrease the rate of photosynthesis in leaf chads.

Prediction: If leaf chads are placed in extreme temperatures (hot and cold), then it will take longer for the chads to photosynthesis and rise to the top compared to the amount of time it takes them to photosynthesis and rise to the top ay room temperature.
]]> 2016-10-15 20:38:52 UTC https://padlet.com/jmohn/p1xbzdnfhzci/wish/130936101 Research Question jmohn https://padlet.com/jmohn/p1xbzdnfhzci/wish/130936102 How will cold and hot temperature change affect the rate of photosynthesis in leaf chads?]]> 2016-10-15 20:38:52 UTC https://padlet.com/jmohn/p1xbzdnfhzci/wish/130936102 Procedure jmohn https://padlet.com/jmohn/p1xbzdnfhzci/wish/130936103
  • Obtain leaf chads from a spinach leaf and place them into a syringe filled with water.
  • Make a vacuum with the syringe to sink the chads, removing all oxygen from the leaf chads.
  • Place the sunken leaf chads into a 300 ml solution of dissolved sodium bicarbonate in distilled water with two drops of detergent at room temperature (20.4 degrees Celsius). Start a timer.
  • Periodically swirl the container to ensure that the leaf chads will rise when buoyancy changes. 
  • Record the time of ET50 (the time at which half of the sunken leaf chads have risen to the top).
  • Repeat steps 1-5 under warm (47 Degrees Celsius) and cold (4.1 Degrees Celsius) conditions by heating or cooling the solution of dissolved sodium bicarbonate in distilled water.
    • ]]>     2016-10-15 20:38:52 UTC https://padlet.com/jmohn/p1xbzdnfhzci/wish/130936103     Conclusion jmohn https://padlet.com/jmohn/p1xbzdnfhzci/wish/130936104 The optimal temperature for photosynthesis in leaf chads is at or around room temperature, between about 20-25 degrees Celsius. This is the temperature at which the rate of photosynthesis is fastest. At (extreme) low temperatures, the enzymes that carry out photosynthesis do not work efficiently. They move very slowly if at all and this decreases the photosynthetic rate. At (extreme) high temperatures, the enzymes that carry out photosynthesis lose their shape and functionality, and photosynthetic rate declines rapidly, eventually coming to a halt. This is important to know because environmentalists can understand more about what temperature plants function and photosynthesis best which will help. The data supports our hypothesis that the hot and cold water (in extremes) decrease the rate of photosynthesis. One possible source of error was a human error of the inconsistent use of cups and volume of solution which could had altered the time that ti took the chads to float to the top. An additional source of error was using multiple leaves in the various temperature trials which could have altered the photosynthesis rate depending on the age of the leaf. ]]> 2016-10-15 20:38:52 UTC https://padlet.com/jmohn/p1xbzdnfhzci/wish/130936104 Results jmohn https://padlet.com/jmohn/p1xbzdnfhzci/wish/130936105 -At room temperature (20.4 degrees Celsius) ET50 was at 5 mins 25 secs.
    The rate of photosynthesis is .00309 seconds 
    -At warm temperature (47 degrees Celsius) ET50 was at 20 mins (1200 secs)
    The rate of photosynthesis is .00083 seconds
    -At cold temperature (4.1degrees Celsius) ET50 was at 20 mins (1200 secs)
    The rate of photosynthesis is .00083 seconds

    The warm and cold temperatures were estimated due to lack of class time to finish the experiment. Half of the chads never fully rose to the top during class when we did the lab but we assumed that eventually they would rise, it would just take a long time due to the enzymes being slowed (in the cool temperature) or heated (in the warm temperature), therefore losing their shape and not being able to function.

    ]]>     2016-10-15 20:38:52 UTC https://padlet.com/jmohn/p1xbzdnfhzci/wish/130936105     How photosynthesis is affected in leaf chads by extreme temperature change sphburge https://padlet.com/jmohn/p1xbzdnfhzci/wish/131499859 Names: Sophie, Caitlin, Riya, Aryan]]> 2016-10-18 14:59:02 UTC https://padlet.com/jmohn/p1xbzdnfhzci/wish/131499859