This activity has been archived while we produce a more up-to-date version of this activity and the accompanying film. We are hoping the new activity and film will be available by the end of 2021.

In this activity, students construct models of sickle cell hemoglobin fibers inside red blood cells to illustrate how changes in the structure of a protein can affect cell shape, as described in the short film The Making of the Fittest: Natural Selection in Humans.

Students step through a procedure for constructing paper models of wild type and mutant hemoglobin molecules. They build mutant hemoglobin fibers to show how these cause red blood cells to take on a different two-dimensional shape. Students then answer questions to explain how these changes in protein and cell structure relate to disease symptoms.