註釋
Bone and muscles join forces to move us from one place to another. The musculoskeletal system controls our breathing, allows our eyes to focus, and shapes our smiles. It enables us to talk and to eat. Our strong bones support our weight. Skin wraps our body in a tough layer of tissue that keeps moisture in and germs out. Find out how this marvelous system works and learn some amazing facts about muscles, bones and skin.
