Which component is crucial for the structure of bone, as indicated by its presence?

• A. Organic compounds
• B. The osteon
• C. Inorganic calcium salts
• D. Collagen fibers

Answer: (C)

The presence of inorganic calcium salts is crucial for the structure of bone because they provide the hardness and strength necessary for the bone to support weight and withstand mechanical stress. These minerals, primarily hydroxyapatite, contribute to the bone matrix and play a vital role in mineralization, which is the process by which bone tissue becomes hardened due to the deposition of minerals. This mineral composition accounts for approximately 70% of bone weight and is essential for maintaining the overall structure and integrity of the skeletal system.

While organic compounds, osteons, and collagen fibers are also important components of bone, they serve different functions. Organic compounds, including proteins and other materials, support the flexibility and resilience of bone but lack the same mineralized strength provided by inorganic salts. The osteon is a structural unit of bone that contributes to its organization and strength but relies on the mineralized matrix to maintain its integrity. Collagen fibers provide tensile strength and help in the framework of the bone matrix, but without the inorganic calcium salts, the bone would not have the required rigidity to fulfill its support functions effectively.