Module 7: Figure bone cells
Functional organization of bone cells
Bone remodelling depends upon a functional interaction between the three major cell types. Bone formation is carried out by the osteoblasts (green) that lie on the cell surface. As the bone forms, it traps the osteoblasts that gradually transform into osteocytes (blue), which have long extensions that make contact via gap junctions both with themselves and with the other two cell types (red arrows). Bone resorption is carried out by the multinucleated osteoclasts.