Which of the Following Occurs During Endochondral Ossification

Question

Which of the following occurs during endochondral ossification?
A) Osteocytes differentiate within a mesenchymal or fibrous connective tissue.
B) Osteoclasts secrete the organic component of the matrix.
C) Osteoblasts lay down bone on a membranous template.
D) The bone grows in length and in diameter.
E) None of the answers are correct.

Accepted Answer

Endochondral ossification is the process of bone formation from a hyaline cartilage template. As the cartilage model grows, chondrocytes in the center of the cartilage begin to hypertrophy and deposit calcium salts, which eventually leads to the formation of a calcified cartilage matrix. Blood vessels then invade the calcified cartilage, bringing osteoblasts and osteoclasts to the area. Osteoblasts lay down new bone tissue on the surface of the calcified cartilage, forming a primary ossification center. This process continues in both directions along the shaft of the bone, resulting in the growth of the bone in length. Osteoblasts also produce bone tissue around the periphery of the bone, which leads to growth in diameter.