14.1 Introduction Bone apposition and resorption are constantly occurring processes that enable bones to adapt structurally by optimizing their shape and size to meet the physical requirements of their external…

8.1 Introduction The skeleton is essentially responsible for providing not only structural support and protection to the body’s organs but also for serving as a reservoir for calcium, magnesium, and…

10.1 Introduction The biological role of phosphorus in humans and other organisms’ physiology is diverse. Phosphorus is essential for the proper function of a multitude of systems. In addition to…

12.1 Introduction In what constituted a major advance in our understanding of bone biology and disease, several groups working on the genetics of rare human skeletal disorders reported a decade…

9.1 Introduction Parathyroid hormone (PTH) and PTH–related protein (PTHrP) are major polypeptide factors that regulate skeletal physiology and mineral homeostasis. The appearance of the parathyroid glands during the evolution of…

7.1 Introduction Osteocytes are defined as cells embedded in the mineralized bone matrix and compose over 90%–95% of all bone cells . They are regularly dispersed throughout the mineralized matrix,…

2.1 Introduction Bone is a vital, dynamic connective tissue whose structure and composition reflect a balance among its major functions: provision of mechanical integrity for locomotion and for protection of…

5.1 Introduction A unique feature of bone is that it contains specialized cells dedicated to its own destruction. These cells, the osteoclasts, are generally regarded as the only cells capable…