Identify the origin of sympathetic nerve fibres and the location of their ganglia

Options

A. They arise from thoraco-lumber region of spinal cord and form ganglia just beside the vertebral column
B. They arise from thoraco-cervical region of spinal cord and form ganglia just beside the vertebral column
C. They arise from thoraco-sacral region of spinal cord and form ganglia very close effector organ
D. They arise from thoraco-lumber region of spinal cord and form ganglia very close effector organ

Answer

### Step-by-Step Solution

1. **Understanding Sympathetic Nerve Fibers**:
- Sympathetic nerve fibers are part of the autonomic nervous system and are responsible for the body's 'fight or flight' response.

2. **Origin of Sympathetic Nerve Fibers**:
- These fibers originate from the thoracic and lumbar regions of the spinal cord. This is why they are often referred to as the "thoracolumbar outflow".

3. **Location of Ganglia**:
- The ganglia associated with sympathetic nerve fibers are located beside the vertebral column. They form a chain along each side of the vertebral column, known as the sympathetic chain or paravertebral ganglia.

4. **Evaluating the Options**:
- **Option 1**: Correct - They arise from the thoracolumbar region of the spinal cord and form ganglia beside the vertebral column.
- **Option 2**: Incorrect - They do not arise from the thoracocervical region; this region is not associated with sympathetic fibers.
- **Option 3**: Incorrect - They do not arise from the thoracosacral region, and the ganglia are not located close to the effector organs.
- **Option 4**: Incorrect - While they do arise from the thoracolumbar region, the ganglia do not form near the effector organs.

5. **Conclusion**:
- The correct answer is that sympathetic nerve fibers arise from the thoracolumbar region of the spinal cord and their ganglia are located beside the vertebral column.