Adrenaline and noradrenaline are called stress hormones. Why?

Answer

**Step-by-Step Solution:**

1. **Definition of Adrenaline and Noradrenaline**:
- Adrenaline, also known as epinephrine, and noradrenaline, also known as norepinephrine, are hormones produced by the adrenal medulla, which is part of the adrenal glands located on top of the kidneys.

2. **Release Conditions**:
- These hormones are released during stressful situations, commonly referred to as the "3F" conditions: fight, fright, and flight. This means they are activated in response to perceived threats or emergencies.

3. **Physiological Effects**:
- Upon release, adrenaline and noradrenaline trigger several physiological changes in the body:
- **Increased Heart Rate**: This helps pump more blood to vital organs and muscles.
- **Increased Blood Pressure**: This ensures that blood reaches all parts of the body more efficiently.
- **Increased Respiration Rate**: This allows for more oxygen intake, which is crucial for energy production during stressful situations.
- **Pupil Dilation**: This improves vision by allowing more light into the eyes, which can be beneficial in a threatening situation.

4. **Role in Emergency Situations**:
- The combined effects of these hormones prepare the body for rapid response to emergencies, enhancing physical performance and alertness. This is why they are often referred to as "stress hormones."

5. **Conclusion**:
- Due to their critical role in preparing the body to handle stress and emergencies, adrenaline and noradrenaline are classified as stress hormones.

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