What makes up a polymer?

This type of glue that we made is the same kind of glue used by the Egyptians to glue furniture together. I had no idea you could make glue out of milk!
We used our new glue to glue hearts to our lab to show our conclusions.  We talked about that polymer make up plastic toys, Styrofoam cups, clothing, and chewing gum. Polymers are also in the horns of animals, turtle shells and our finger nails!