Which is not the function of bones

Options

A. Protection of vital organs
B. Haemopoiesis
C. Muscle attachment
D. Secretion of hormones.

Answer

To determine which option is not a function of bones, we can analyze each provided option based on the known functions of the skeletal system.

### Step-by-Step Solution:

1. **Understanding the Functions of Bones:**
- Bones are part of the skeletal system and have several key functions, including support, protection, movement, mineral storage, and blood cell production.

2. **Analyzing the Options:**
- **Option 1: Protection of Vital Organs**
- Bones protect vital organs. For example, the rib cage protects the heart and lungs, and the cranium protects the brain. This is a recognized function of bones.

- **Option 2: Hemopoiesis (Formation of Blood Cells)**
- Hemopoiesis occurs in the bone marrow, where blood cells (including red blood cells, white blood cells, and platelets) are produced. This is another established function of bones.

- **Option 3: Muscle Attachment**
- Muscles are attached to bones, allowing for movement. For instance, the deltoid muscle attaches to the humerus. This is a fundamental function of bones.

- **Option 4: Secretion of Hormones**
- Bones do not secrete hormones. Hormone secretion is a function of the endocrine system, not the skeletal system. Therefore, this option does not represent a function of bones.

3. **Conclusion:**
- Based on the analysis, the correct answer to the question "Which is not the function of bones?" is **Option 4: Secretion of Hormones**.

### Final Answer:
**Option 4: Secretion of Hormones is not a function of bones.**