Fascinating story

hye,i'm back..today i'll continue about the fascinating story about us that i told u yesterday,the story begin..when we were very,very young,in fact before you were born,you already has a good part of your skeleton.It was not made of bone,but of a softer material called cartilage.You still have cartilage giving shape to parts of you,such as the outer ear and the lower part of your nose.Bit by bit the cells of cartilage were replaced by bone cells.Bone cells are just as soft as any other cells,but they can do a remarkable thing.These cells take dissolved minerals,mainly calcium and phosporus,from the blood.They turn the minerals into the hard materials we hard think of as bone.The cells surround themselves with bone,and continue to live inside their self-made bony prison.This process goes on now,too,as you go on growing.The calcium and other minerals needed to form strong bone come from the foods you eat such as milk.To be continued...wait..