A maximum number of free vertebrae in humans are found in

Options

A. thoracic region
B. cervical region
C. lumber region
D. coccygenal region

Answer

To solve the question regarding the maximum number of free vertebrae in humans, we need to analyze the vertebral column and its regions:

1. **Understanding the Vertebral Column**: The human vertebral column is composed of 26 vertebrae, which are categorized into different regions: cervical, thoracic, lumbar, sacral, and coccygeal.

2. **Identifying the Regions**:
- **Cervical Region**: Contains 7 vertebrae (C1 to C7).
- **Thoracic Region**: Contains 12 vertebrae (T1 to T12).
- **Lumbar Region**: Contains 5 vertebrae (L1 to L5).
- **Sacral Region**: Typically consists of 5 fused vertebrae (S1 to S5) forming the sacrum.
- **Coccygeal Region**: Usually consists of 4 fused vertebrae forming the coccyx.

3. **Counting Free Vertebrae**:
- Free vertebrae are those that are not fused.
- In the cervical region, all 7 vertebrae are free.
- In the thoracic region, all 12 vertebrae are free.
- In the lumbar region, all 5 vertebrae are free.
- The sacral and coccygeal regions consist of fused vertebrae and do not contribute to the count of free vertebrae.

4. **Calculating the Total Number of Free Vertebrae**:
- Cervical: 7 free vertebrae
- Thoracic: 12 free vertebrae
- Lumbar: 5 free vertebrae
- Total free vertebrae = 7 (cervical) + 12 (thoracic) + 5 (lumbar) = 24 free vertebrae.

5. **Identifying the Region with Maximum Free Vertebrae**:
- Among the cervical, thoracic, and lumbar regions, the thoracic region has the highest number of free vertebrae, which is 12.

6. **Conclusion**: Therefore, the maximum number of free vertebrae in humans is found in the **thoracic region**.