Lengthwise, long bone growth during infancy and youth is exclusively through

The epiphyseal plates can be defined as the area of the growth present in the long bones. All the long bones grows by the interstitial growth of the epiphyseal plates.

The epiphyseal growth plate or the growth plate is present near the end of the long bones of the infants and the adolescents. It is a disc like structure made up of hyaline cartilage.

Hence, the correct answer is interstitial growth of the epiphyseal plates.

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