Bone cells and tissues - tissue composition and cells
Date Uploaded: 09/09/2019
Bone tissue consists of bone cells secreting bone matrix. • The extracellular bone matrix is a connective tissue that is hard, yet flexible. • Collagen fibers provide flexibility. • Inorganic mineral salts (primarily calcium phosphate, or hydroxyapatite) provide hardness. • Together the calcium salts and fibers provide the ability to endure longitudinal stress. • Mesenchymal cells are connective tissue cells that play a central role in bone development. • Osteogenic cells (derived from mesenchymal cells) undergo cell division and develop into osteoblasts. • Osteoblasts secrete osteoid, (mostly collagen fibers) and initiate calcification of the matrix. • Osteoblasts trapped in lacunae mature into osteocytes. • Osteocytes (derived from osteoblasts) are mature bone cells that maintain bone matrix. • Osteoclasts (formed by fusion of monocytes) break down the bony matrix, releasing minerals into bloc) stream. • The body uses bone matrix as a storage site for calcium and phosphate ions. These cells work to make deposits or withdrawals of those ions as needed.
You must login to add videos to your playlists.