If you ask most kids what bones are made of, they would quickly answer “calcium!” Though it’s not incorrect, years of us telling them to drink their milk for strong bones has hidden an amazing feature of nature, biomineralization by proteins. Calcium is only half the story of bones. Though the semi-crystalline mineral that contains calcium, oxygen, hydrogen, and phosphorus, called hydroxyapatite, provides strength and rigidity, our bones also need to be elastic to help absorb shock. This is where proteins come in. Your bones are made of living tissue that spew out networks of protein that trap and crystallize the calcium in your body. Together they form the strong, resilient biomaterial we know as bones.
You can feel the flexibility of the protein network for yourself by reacting and dissolving the hydroxyapatite from the bones in vinegar. What’s left are entertaining, wiggly bones the kids will love to play with (except my daughter, who was too grossed out and didn’t want to touch them which is why all these pictures are of my hands ¯\_(ツ)_/¯ ).
Continue reading “How to Make Bendy Bones”
