BIOMOLECULES AND ENZYMES

Detailed explanation-1: -Osteoclasts: these are bone resorbing cells. Osteoid: this is the non-mineral, organic part of the bone matrix made of collagen and non-collagenous proteins.

Detailed explanation-2: -Osteoclasts and osteoblasts are the bone resorbing cells and bone-forming cells, respectively. Whereas multinucleated bone resorbing osteoclasts differentiate from mononuclear cells of the monocyte/macrophage lineage (7), osteoblasts are derived from mesenchymal stem cells (MSC) (8).

Detailed explanation-3: -Osteoclasts Resorb Bone The area of the osteoclast next to bone forms a “ruffled border” consisting of multiple infoldings of the osteoclast cell membrane. It secretes acid and proteases across the ruffled border, and these dissolve the mineral of bone and destroy the organic matrix (see Figure 9.8.

Detailed explanation-4: -Bone is resorbed by osteoclasts, and is deposited by osteoblasts in a process called ossification. Osteocyte activity plays a key role in this process. Conditions that result in a decrease in bone mass can either be caused by an increase in resorption or by a decrease in ossification.