What is the process of bone formation in the fetus and summarizes the events of bone remodeling throughout life?

Answer 1

Bone starts as cartilage in the fetus. As the fetus takes on the final shape, this cartilage arranges, and enough hardening occurs in the limbs to allow the creature to stand shortly after birth. At that point, all the bones begin to harden, and continues to harden all throughout life. Bones contain a level of cartilage all the way until old age.

Answer 2

In the fetus, bones initially form through a process called endochondral ossification, where cartilage is replaced by bone tissue. This process involves the deposition of minerals into the cartilage scaffold, leading to the formation of primary ossification centers.

Throughout life, bone remodeling occurs through a delicate balance of bone resorption by osteoclasts and bone formation by osteoblasts. This process helps maintain bone strength and repair microdamage. As we age, this balance can shift towards more bone resorption, leading to conditions like osteoporosis.

Answer 3

The fetus has cartilage "bones" enclosed by "bony" bones. Then, the enclosed hyaline cartilage model is digested away, opening up the medullary cavity within the newly formed bone.