The major inorganic salt that is stored in the bones is calcium phosphate. In humans bone formation starts during early embryogenesis and that is when the embryo is about eight weeks old.
a. During very early development in human embryo, the bones are membranous structures made of hyaline cartilage; calcium phosphate is required for intramembranous ossification in skeleton system. It is the process for the formation of membrane bone of the embryo.
b. Subsequently embryonic cartilage is formed by endochondral ossification and the process needs calcium phosphate.
c. Finally, the same substance is essential during primary ossification where cartilage is replaced by solid bone as well as during post-natal bone growth of the infant and baby.
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