What is the major organic compound found in bone?

• A. Calcium phosphate
• B. Collagen
• C. Vitamin D
• D. Keratin

Answer: (B)

The major organic compound found in bone is collagen. Collagen is a type of protein that provides the structural framework for bone tissue. It plays a critical role in bone strength, flexibility, and overall integrity. Approximately 90% of the organic matrix of bone is made up of collagen, which contributes to the bone's ability to withstand tension and support weight.

In addition to collagen, the organic matrix of bone also contains other proteins and carbohydrates that are essential for bone health. However, collagen is the predominant component and is crucial for the development and maintenance of the bone architecture.

The other choices—calcium phosphate, vitamin D, and keratin—are either minerals or biological compounds that contribute in different ways but do not comprise the major organic matrix. For instance, calcium phosphate is primarily an inorganic mineral that gives bone its hardness and rigidity, while vitamin D is important for calcium absorption but does not form part of the bone matrix itself. Keratin, a protein found in skin and hair, is not present in bone tissue. Thus, collagen's vital role as the main organic compound highlights its significance in skeletal health and function.