Which of these is a correct count of the spinal nerves in man ?

Options

A. 9 Cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
B. 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
C. 7 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
D. 8 cervical, 11 thoracic, 4 lumbar, 6 sacral, 1 coccygeal

Answer

To determine the correct count of spinal nerves in humans, we need to analyze the different types of spinal nerves and their respective counts.

### Step-by-Step Solution:

1. **Identify the Types of Spinal Nerves**:
- In humans, spinal nerves are categorized into five regions: cervical, thoracic, lumbar, sacral, and coccygeal.

2. **Count the Cervical Nerves**:
- There are **8 cervical nerves** (C1 to C8).

3. **Count the Thoracic Nerves**:
- There are **12 thoracic nerves** (T1 to T12).

4. **Count the Lumbar Nerves**:
- There are **5 lumbar nerves** (L1 to L5).

5. **Count the Sacral Nerves**:
- There are **5 sacral nerves** (S1 to S5).

6. **Count the Coccygeal Nerve**:
- There is **1 coccygeal nerve** (Co1).

7. **Summarize the Counts**:
- Therefore, the total counts are:
- 8 cervical
- 12 thoracic
- 5 lumbar
- 5 sacral
- 1 coccygeal

8. **Evaluate the Options**:
- Based on the counts, we can evaluate the options provided in the question:
- **Option 1**: 9 cervical - Incorrect
- **Option 2**: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal - Correct
- **Option 3**: 7 cervical - Incorrect
- **Option 4**: 8 cervical, 11 thoracic - Incorrect (11 thoracic is wrong)

9. **Conclusion**:
- The correct count of spinal nerves in humans is **8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal**. Therefore, the correct answer is the second option.