An osteoblast (from the Greek words for "bone" and "to build") is a mononucleate cell that produces a protein that produces osteoid. Grays illustration of a human femur, a typically recognized bone. ... It has been suggested that extracellular be merged into this article or section. ... Osteoid is a protein mixture which is secreted by osteoblasts. ...

Osteoblasts arise when osteoprogenitor cells (mesenchymal cells), which are located near all bony surfaces and within the bone marrow, differentiate under the influence of growth factors, such as fibroblast growth factor (FGF), platelet-derived growth factor (PDGF), transforming growth factor beta (TGF-β) and other bone morphogenetic proteins (BMPs). Mesenchymal cells also known as mesenchymal stem cells or marrow stromal cells (MSC) are stem cells that can differentiate into osteoblasts, chondrocytes, myocytes, adipocytes neuronal cells and - as decribed lately, into beta-pancreatic islets cells. ... Growth factor is a protein that acts as a signaling molecule between cells (like cytokines and hormones) that attaches to specific receptors on the surface of a target cell and promotes differentiation and maturation of these cells. ... Platelet-derived growth factor (PDGF) is one of the numerous proteins that regulate cell growth and division. ... Transforming growth factor (TGF) is one of many characterized growth factors that exist in nature. ... Bone morphogenetic proteins (BMPs) are growth factors belonging to the TGF-β (Transforming Growth Factor-beta) super family with a strong ability to induce new bone and/or cartilage formation. ...

In addition to osteoid, osteoblasts also secrete enzymes that facilitate mineral deposition within osteoid matrices. They are also responsible for regulating the activity of osteoclasts via soluble mediators. Osteoblasts that become trapped in the bone matrix become osteocytes. Ribbon diagram of the enzyme TIM. TIM is catalytically perfect, meaning its conversion rate is limited, or nearly limited to its substrate diffusion rate. ... Minerals are natural compounds formed through geological processes. ... In biology, extracellular matrix (ECM) is any material part of a tissue that is not part of any cell. ... An osteoclast is a multinucleated cell that degrades and reabsorbs bone. ... An osteocyte, a star-shaped cell, is the most abundant cell found in bone. ...

ACTIVATED OSTEOBLAST:The cytoplasm appear to be basophilic via normal H&E stain due to presence of large amount of rER A large Golgi apparatus is also present in the centre.The nucleus is spherical and large. The endoplasmic reticulum or ER (endoplasmic means within the cytoplasm, reticulum means little net) is an organelle found in all eukaryotic cells. ...