Skull bone
The flat bones of the skull grow and develop through the process of the intramembranous ossification, which begin in the fetus around 2 months after fertilization. Fibrous connective tissue membranes from the bone models.ossification centers develop inside the membranes , lay down a bone matrix, and eventually produce a latticework of spongy bone surrounded by compact bone. At birth, ossification is still incomeplete and the skull bones are connected by unossified sections of fibrous membranes at the fontanelles. The fontanelles close by around the ages of two. The presence of these flexible, fibrous joints allows changes in the shape of the skull, facilitating the passage baby through the brith canal