What makes up about 90% of bone protein?

What makes up about 90% of bone protein?

• A. Collagen
• B. Osteoblasts
• C. Osteocytes
• D. Osteoclasts

Answer: (A)

Collagen is the main protein in bone, forming the majority of the organic matrix. It makes up roughly 90% of the bone’s protein content, providing a fibrous, flexible framework (the osteoid) on which minerals like calcium phosphate deposit to create a strong yet resilient bone. The other options are bone cells—osteoblasts build bone, osteocytes maintain it, and osteoclasts resorb it—so they are not proteins themselves. That’s why collagen best fits the idea of “about 90% of bone protein.”

Collagen is the main protein in bone, forming the majority of the organic matrix. It makes up roughly 90% of the bone’s protein content, providing a fibrous, flexible framework (the osteoid) on which minerals like calcium phosphate deposit to create a strong yet resilient bone. The other options are bone cells—osteoblasts build bone, osteocytes maintain it, and osteoclasts resorb it—so they are not proteins themselves. That’s why collagen best fits the idea of “about 90% of bone protein.”