Bone is mainly composed of

Options

A. iron and phosphorus
B. sulphur and calcium
C. calcium and phosphorus
D. calcium and magnesium

Answer

**Step-by-Step Solution:**

1. **Understanding Bone Composition**: Bones are complex structures made up of both organic and inorganic components.

2. **Identifying Organic Components**: The organic part of bone mainly consists of collagen fibers, which provide flexibility and tensile strength. Additionally, glycoproteins and proteoglycans are present, which contribute to the structure of the bone matrix.

3. **Identifying Inorganic Components**: The inorganic part of the bone primarily consists of mineral salts. The most significant of these are calcium and phosphate.

4. **Recognizing Major Salts**: The main inorganic salt found in bones is hydroxyapatite, which is a compound made up of calcium and phosphate.

5. **Evaluating Options**: Given the options provided in the question, the correct answer is the one that includes both calcium and phosphorus, as these are the primary constituents of bone.

6. **Conclusion**: Therefore, the answer to the question "Bone is mainly composed of" is calcium and phosphorus.

**Final Answer**: Bone is mainly composed of calcium and phosphorus.

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