Bones are hard organs made of minerals and connective tissue.If you looked inside a bone, you would notice two kind of bones tissues : one kind is called compactbone and the other is called spongy bone.
they have blood vessels wich supply nutrients and neveres which signalpain. The body of a newborn baby has about 300 bones, but the average adult has only 206. As a child grow, some bones fuse together.
The skeleton of a fetus growing inside its mother body does not contain hard bones. Insitesd, most bones star out as flexiblescartilage. When a baby is born, it still has a lot of cartilage. As the baby grows, most of the cartilage is replace by bone. The bones of child continue to grow. The longbones lengthen at their ends, in areas called growth plates. Growth plates are areas of cartilage that continue to make new cells. Bone cells called osteocytesmoves into the cartilage,hardening it and changing it into early adulthood. Most bones harden completely after they stop growing. Even after bones have stopped growing,they can still repair themselves if they break.
Bones are connect:
The place where two or more bones are connect is called joint. Somejoint allow movement of body parts, other stop or limits movement. Just imagine how difficult it woulbe to do everyday things such as trying your shoelasces if youcould not bend the joints in your arms,legs, neck, or fingers.
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