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 can follow these steps:

### Step 1: Understand the Types of Vertebrae
Humans have a total of 26 vertebrae, which are categorized into different regions:
- **Cervical Region**: 7 vertebrae
- **Thoracic Region**: 12 vertebrae
- **Lumbar Region**: 5 vertebrae
- **Sacral Region**: 1 vertebra (fused)
- **Coccygeal Region**: 1 vertebra (fused)

### Step 2: Identify Free vs. Fused Vertebrae
- Free vertebrae are those that are not fused together.
- In the human spine, the sacral and coccygeal vertebrae are fused, meaning they do not count as free vertebrae.

### Step 3: Count the Free Vertebrae in Each Region
- **Cervical Region**: 7 free vertebrae
- **Thoracic Region**: 12 free vertebrae
- **Lumbar Region**: 5 free vertebrae
- **Sacral Region**: 1 fused vertebra (not free)
- **Coccygeal Region**: 1 fused vertebra (not free)

### Step 4: Compare the Number of Free Vertebrae
Now, we can compare the number of free vertebrae in the cervical, thoracic, and lumbar regions:
- Cervical: 7
- Thoracic: 12
- Lumbar: 5

### Step 5: Determine the Maximum
From the counts above, the thoracic region has the highest number of free vertebrae, which is 12.

### Conclusion
Thus, the maximum number of free vertebrae in humans is found in the **thoracic region**.

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