figure4

Figure 4. Osteoclasts and the Mechanism of Bone Resorption. A: Light micrograph and B: electron micrograph of an osteoclast, demonstrating the ruffled border and numerous nuclei. C: Osteoclastic resorption. The osteoclast forms a sealing zone via integrin mediated attachment to specific peptide sequences within the bone matrix, forming a sealed compartment between the cell and the bone surface. This compartment is acidified such that an optimal pH is reached for lysosomal enzyme activity and bone resorption.