Intramembranous Ossification

• Locate regions of intramembranous bone development in the sections of fetal rodent head on.
• Identify the periosteum and as many of the bone cells as possible.

Where would you expect mesenchyme to persist the longest during formation of the skull?

What is happening chemically in osteoid that converts it to bone?

Endochondral Ossification

Concentrate on the chondrocytes and matrix, noting the changes in these structures as you move through the various functional zones.

• zone of reserve cartilage
• zone of chondroblast proliferation
• zone of chondrocyte hypertrophy
• zone of cartilage calcification and chondrocyte degeneration
• zone of osteogenesis

Why are periosteal cells and osteoprogenitor cells not necessarily the same thing?

List exactly what is happening at the cellular level of you move from the epiphyseal cartilage to the diaphyseal bone marrow.

Joint formation is next.