<Tr> <Td> By 25 years </Td> <Td> Nearly all bones are completely ossified </Td> </Tr> <P> Intramembranous ossification forms the flat bones of the skull, clavicle and mandible . </P> <P> Endochondral ossification is the formation of long bones and other bones . This requires a hyaline cartilage precursor . There are two centres of ossification for endochondral ossification . </P> <P> The primary centre </P>

Where does the ossification of long bones begin