Growth plate, light micrograph. The growth plate of long bones is the interface between maturing chondrocytes (right) and newly forming bone tissue (left) and is termed the epiphyseal growth plate. terminally differentiated the hypertrophied chondrocytes degenerate but their secreted cartilage (purple) is retained as honeycomb-like extensions upon which bone matrix is deposited by osteoblasts (blue). Bone growth via growth plates is referred to as endochondral ossification. Methacrylate section, Toluidine blue stain. Magnification: x 400 when width printed at 10cm.