This lesson focuses on the diffusion of gas molecules across the cuticle membrane of sea spider legs and the role body size plays in the ability of sea spiders to uptake gases. Students construct model sea spider legs of varying diameters and use them to investigate the relationship between surface area-to-volume ratios and diffusion.
In this investigation, students will measure production of CO2 from surface water and consider the role of surface waters in the global carbon cycle and climate change. They will gather data on using Vernier CO2 sensors. This lesson presents a wonderful opportunity for student-designed experiments.
This is a good lesson to get students thinking about the complexity of the systems involved in providing our society with energy, the consequences of energy use and efficiency. Students are encouraged to explore the data sets on their own, ask their own questions about energy use and present their findings to each other.