2. Osteoblasts build the bone collar on the external surface of the bone. 3. Perichondrium is invaded by blood vessels. 4. In the primary ossification center, osteoblasts replace calcified cartilage with early spongy bone. 5. Perichondrial cells differentiate into osteogenic cells then into osteoblasts. read more
Place the following steps of bone repair in the correct sequence. 1. The bone callus is remodeled and primary bone is replaced with secondary bone. 2. A hematoma fills the gap between bone fragments. 3. Osteoblasts built a new bone callus. 4. Fibroblasts and chondroblasts infiltrate the hematoma and a soft callus forms. read more