Bones

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Bones are a kind of hard endoskeletal connective tissue that is found in all vertebrates. Bones give bodies their structure and protect internal organs. Muscles are attached to bone and they expand and contract to allow movement. The adult human body has 206 bones; the smallest is the stirrup, which is inside the ear. It is less than an inch long. Children are born with 300 bones--some consist of hard connective tissue and others are made of cartilage. Over time, the cartilage hardens and turns to bone and some bones fuse together. This accounts for the larger number of bones in children than in adults. This is also why younger children tend to fracture more bones than adults—young bones are more flexible. Furthermore, children are more inclined than adults to take risks with their bodies and break bones.