Fig. 2.

Formation of the cartilage anlage during development. During the mesenchymal condensation phase, mesenchymal cells (blue) condense. Subsequently, during the chondrogenesis phase the cells differentiate into chondrocytes (green). Perichondrium cells are also formed (yellow). During the hypertrophic differentiation phase, chondrocytes in the central zone undergo hypertrophy (pink) to initiate the formation of the growth plate