Resting Zone: epiphyseal side (no mitosis) Proliferating cartilage zone: mitosis Hypertrophic cartilage zone: cartilage cells enlarging, older chondrocytes in stack are closer to diaphysis, lacunae erode and enlarge, leaving interconnecting spaces Calcified cartilage zone: dying cartilage cells on diaphyseal plate , matrix begins to deteriorate, allowing blood vessels to invade Ossification Zone: calcified spicules are invaded marrow elements from mudullary cavity, osteoclasts partly erode cartilage spicules then osteoblasts cover them with new bone