Which cells are responsible for the reabsorption of previously laid down bone?

The cells responsible for the reabsorption of previously laid down bone are osteoclasts. These specialized cells play a crucial role in bone remodeling by breaking down bone tissue. They secrete enzymes and acids that dissolve the minerals and collagen matrix of the bone, allowing calcium and phosphate to enter the bloodstream. This process is essential for maintaining bone health and calcium homeostasis in the body.

Osteoblasts, on the other hand, are responsible for the formation of new bone, while osteocytes, which are mature bone cells derived from osteoblasts, maintain bone tissue and communicate with other cells in the bone matrix. Chondrocytes are involved with cartilage formation, not bone reabsorption. Therefore, osteoclasts are uniquely suited for the reabsorption function, highlighting their critical role in the ongoing cycle of bone remodeling.