January 20, 2014
Period A
Bone Development and Growth
Dawn A. Tamarkin, PhD.
STCC Foundation Press
2011
Summary of the Article:
There are two different ways for bones to develop:
-embryonically: cells differentiate from other cells and grow to form organs and tissues.
-postembryonically: any type of development changes that occur after one is born.
The term for the formation of bones is ossification. Most bones start off as cartilage and then grow to bone. This is an example of endochondral ossification.
Embryonic Development
Intramembranous Ossification
Intramembranous ossification occurs within a membrane and produces a flat type of bone.
Connective tissues form in sites where intramembranous bones will eventually be formed. The connective tissues possess a high amount of blood cells, which form spongy bone. Connective tissues harden, and compact bone is formed.
Endochondral Ossification
In this type of ossification, bone forms by replacing hyaline cartilage.
Chondrocytes within the cartilage begin to die. At that time, a periosteum forms around the cartilage. It produces osteoblasts, which build between and around the spongy bone. Compact bone begins to form from the osteoblasts.