The Biology and AP Biology classes at SHS performed lab experiments to see the process of diffusion.
Biology
During this lab, the students placed their eggs in a vinegar solution to dissolve the outer shell leaving the egg's membrane intact. Students then placed the egg in syrup, which diffused the water from inside the eggs dehydrating them. Finally, the eggs were submerged in distilled water with food coloring so students could clearly see the process. The eggs represented cells in the body at states of isotonic, hypertonic, and hypotonic.
AP Biology
AP Biology students performed a lab using dialysis tubing to represent a semipermeable membrane. The tubes were filled with a sugar solution and a starch solution. The sugar tube was placed in a normal glass of water, while the starch tube was placed in a water, iodine solution. Over a period of time, students were able to see the various solutions change as the contents of the tubes either diffused into the surrounding waters or the contents of the surrounding water diffused into the tubes. With the starch solution, the iodine made its way through the tubing to mix with the starch to make a dark purple color. The green sugar solution seeped its way out of the tubing to mix with the surrounding water.
