Schematic of bone development form a cartilaginous precursor (chondral ossification). The ossification starts at the diaphysis of as long bone of the fetus (primary ossification centre). In later states (after birth) secondary ossification centres form in the epiphyses (end parts) of the bone, they grow and, until the end of long bone length growth, leave an enpiphyseal plate at the connection to the shaft.
