Anatomy / Physiology

Front 1

stem cells that develop from embryonic mesenchymal cells (see p. 145) and then give rise to most other bone cell types. They are found in the endosteum, the inner layer of the periosteum, and in the central canals. They multiply continually, and some go on to become the osteoblasts described next.

Back 1

Osteogenic10 (osteoprogenitor) cells

Front 2

bone-forming cells. They are roughly cuboidal or angular, and line up in a single layer on the bone surface under the endosteum and periosteum and resemble a cuboidal epithelium. They synthesize the soft organic matter of the bone matrix, which then hardens by mineral deposition.

Back 2

Osteoblasts

Front 3

are former osteoblasts that have become trapped in the matrix they deposited. They reside in tiny cavities called lacunae,12 which are interconnected by slender channels called canaliculi13 (CAN-uh-LIC-you-lye).

Back 3

Osteocytes

Front 4

re bone-dissolving cells found on the bone surface. They develop from the same bone marrow stem cells that give rise to the blood cells. is formed by the fusion of several stem cells They typically have 3 or 4 nuclei, but sometimes up to 50, each contributed by one stem cell.

Back 4

Osteoclasts