Which zone is defined by calcification?

Which zone is defined by calcification?

• A. Calcification Zone
• B. Ossification Zone
• C. Proliferation Zone
• D. Hypertrophic Zone

Answer: (A)

Calcification is the defining feature of the Calcification Zone. In endochondral ossification, after chondrocytes proliferate and then enlarge (hypertrophy), the surrounding cartilage matrix becomes calcified in this zone. This calcified cartilage then serves as a scaffold for invading osteoblasts that will lay down bone in the next step, the Ossification Zone. So the Calcification Zone is specifically the region where the cartilage matrix calcifies, distinguishing it from the Proliferation Zone (cell division), the Hypertrophic Zone (cell growth), and the Ossification Zone (bone formation).

Calcification is the defining feature of the Calcification Zone. In endochondral ossification, after chondrocytes proliferate and then enlarge (hypertrophy), the surrounding cartilage matrix becomes calcified in this zone. This calcified cartilage then serves as a scaffold for invading osteoblasts that will lay down bone in the next step, the Ossification Zone. So the Calcification Zone is specifically the region where the cartilage matrix calcifies, distinguishing it from the Proliferation Zone (cell division), the Hypertrophic Zone (cell growth), and the Ossification Zone (bone formation).