The hardness of bone is due to the deposition of

  • A. salts of calcium, such as calcium phosphate
  • B. silica particles
  • C. sodium chloride crystals
  • D. chitin fibres

Explanation

Bone combines a flexible framework of collagen with hard calcium salts, giving both strength and a little spring. Without the mineral component bone would bend, and without collagen it would shatter, which is why both parts matter.

Related questions