Best of the Week 2018-2019: Excellence in College Prep

IB BIOLOGY STUDENTS DESIGN & CONDUCT THEIR OWN LAB TO UNDERSTAND THE FACTORS THAT AFFECT PHOTOSYNTHESIS

This week, students in Mrs. Amanda Nugent's IB Biology SL class designed and conducted their own lab experiment focused on analyzing factors that affect the rate of photosynthesis. As their subject, students used spinach leaves as their subject that were hole-punched into disks and prepared within a vacuum to remove any air, allowing them to sink in water. Students watched as the disks sank when submerged in water and then slowly rose to the surface due to the production of oxygen gas, signaling a successful occurrence of photosynthesis. Students' labs varied in measurement and analysis procedures. They measured the time that each disk took to rise to the water's surface in order to calculate the exact rate of photosynthesis, recorded the age of each spinach leaf prior to preparation and even measured the wavelength of light that the disks were subjected to during the process. The way each student designed his lab procedures produced varying results that will contribute to understanding how many factors affect the rate of photosynthesis.

Photosynthesis is an integral part of energy transformation. The purpose of this lab was not only for students to design and conduct a lab completely on their own, but to also understand how factors within and out of human control can affect how natural energy is made in order for plant-life to survive. Students are currently working on compiling their results to present to their class next week.

"This simple lab design allowed students to experience inquiry in the laboratory setting and to extend their knowledge to design their own labs," says Mrs. Nugent. Because very little was initially given to students in terms of lab procedure, students had to work independently and collaboratively to determine how to create each step of the experiment, how to properly measure the rate of photosynthesis and how to problem solve if the lab didn't work as intended. "College lab-based courses are designed to provide the basics of an exercise with the expectation that the students will work on their own using prior knowledge to complete the lab," says Mrs. Nugent. "Having students work independently in the lab, with some help from their peers, provides them with invaluable skills that can be used in the college laboratory setting."