Osteoblasts
Osteoblasts are bone-forming cells. They come from the same cell line as the connective tissue and fat cells. Osteoblasts almost always lie close together in a layer epithelium similar to each other and have contact with each other via short, delicate appendages.
The cytoplasm of relatively small osteoblasts has a pronounced Golgi apparatus, is rich in mitochondria and granular endoplasmic reticulum. The osteoblasts produce the intercellular substance of bone tissue consisting of basic substance and collagen fibres and replace degraded bone over a period of several weeks.