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.
When radioactive elements decay they emit high-speed particles. These can be detected by use of a cloud chamber. The cloud chamber was invented by Charles Thomson Rees Wilson in 1911. The chamber works by saturating the air inside with alcohol vapor. Cooling the chamber with dry ice supersaturates the air. The energetic particles produced by the radioactive decay ionize