Human vertebral column has

Options

A. Four curves
B. No curves
C. Three curves
D. Two curves.

Answer

To answer the question regarding the number of curves in the human vertebral column, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Vertebral Column**: The human vertebral column, also known as the spine, is made up of individual vertebrae stacked on top of each other. It provides structural support and protects the spinal cord.

2. **Identifying the Curvatures**: The vertebral column has specific curvatures that help in weight distribution and balance. These curvatures are classified into two categories: primary and secondary.

3. **Primary Curvatures**:
- There are two primary curvatures that are retained from fetal development:
- **Thoracic Curve**: This curvature is located in the thoracic region and consists of thoracic vertebrae.
- **Sacrococcygeal Curve**: This curvature is found in the sacral and coccygeal regions.

4. **Secondary Curvatures**:
- There are two secondary curvatures that develop after birth as the child grows and learns to sit, stand, and walk:
- **Cervical Curve**: This curvature develops as the infant begins to lift its head.
- **Lumbar Curve**: This curvature develops as the child starts to walk.

5. **Total Number of Curvatures**: By combining the primary and secondary curvatures, we find that the human vertebral column has a total of four curvatures:
- Primary: Thoracic and Sacrococcygeal
- Secondary: Cervical and Lumbar

6. **Conclusion**: Therefore, the correct answer to the question "Human vertebral column has" is **four curves**.

### Final Answer:
The human vertebral column has **four curves**.

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