How does the skeletal system work?

Your skeleton is 206 living bones: a frame, a shield, a set of levers and a blood factory. Count every bone, cut a femur open, bend five kinds of joint, feel how hard your biceps pulls, watch a growth plate close and a broken bone knit.

Read how it works: How does the skeletal system work? · The history of the skeleton · More boxes on Glassbox

Chapters in this interactive model

1. 206 bones, head to toe: A frame, a shield, a set of levers and a factory, all in one.
2. Inside a bone: a living tube: Hard shell, spongy ends, marrow in the middle, and why a tube beats a rod.
3. Where bones meet: joints: Hinges, balls in sockets, pivots, sliders and seams, oiled by cartilage and fluid.
4. Levers, loads and a strong spine: Your muscles pull hard so your hands can move fast, and your bones take the strain.
5. Bone is alive: rebuilt and growing: Cells that dig and cells that build, a bank of calcium, and the plates that make you taller.
6. Breaks, thinning, wear and curves: How bones heal, what goes wrong with age, and how to keep them strong.