Intramembranous ossification

Definition

Intramembranous ossification is a process by which certain bones, such as some of the skull bones and clavicle, are formed directly from mesenchymal (loosely organized embryonic) tissue without first being cartilage. This process contributes to the formation of the flat bones of the skull, mandible, and clavicle.

Related terms

Osteoblasts:

Cells that secrete the matrix for bone formation and are responsible for bone growth.

Mesenchyme:

Embryonic connective tissue from which all tissues develop, serving as the starting material for intramembranous ossification.

Ossification:

The process by which bone is formed, renewed, and repaired in the body through the deposition of calcium into a collagen matrix