Based on OpenSciEd's Metabolic Reactions unit. Students finish their graphs from the villi simulation. They complete a graph on paper and using a spreadsheet, then answer reflection questions. Students should decide that taller villi allow for more food absorption because they have more cells, and more cells mean more "doorways" the food molecules can go through. Most will also decide that M'Kenna's villi are probably short or flat. If they need further evidence they can think about the small in