Question

flat bones of the face and skull are formed by which of the following processes, in which compact and spongy bone develops directly from sheets of undifferentiated connective tissue?
a.) endochondral ossification
b.) intramembranous ossification
c.) interstitial growth
d.) appositional growth

Explanation:

• Endochondral ossification: Replaces cartilage with bone, forms most bones (e.g., long bones), not flat skull/face bones.
• Intramembranous ossification: Directly forms bone from connective tissue sheets (mesenchyme), creates flat bones (skull, facial bones).
• Interstitial growth: Increases cartilage length (during childhood), not bone - formation process.
• Appositional growth: Increases bone/cartilage width (via periosteum), not initial bone - formation from connective tissue.

Answer:

B. Intramembranous ossification