Describe what is happening at the epiphyseal growth plate during endochondral ossification
In the epiphyseal cartilage there are chondroblasts producing daughter cells which produce more cartilaginous matrix. As the process continues they get further away from the epiphyseal cartilage and cells move into the reserve zone. In this zone the chondrocytes align in concert with each other. As they move further away from where proliferation occurs the cells are changing - in this area they start to die off. In the hypertrophic zone the cells that were chondrocytes die, attract minerals, become encased in mineralised matrix and wait for the advancing front of the vascular zone to come in and dissolve them away. The cells are then laid down as osteoblasts and the bone proper is formed.