The process in which cartilage is gradually replaced by bone is called what?
Ossification or the process of bone formation occurs in two ways :
In intramembanous ossification, bone is formed by direct mineralization of matrix. The flat bones of skull (frontal, parietal, part of occipital and temporal) are formed by this process.
In case of endochondral ossification , bone is formed by gradually replacing a cartilage. This type of ossification occurs in the process of formation of long and short bones (the bones of arm and leg).
Following diagram shows the stages of endochondral ossification in case of formation of a long bone, here we can see how a cartilage is gradually being replaced by a bone.