Which of the following is an action not produced by sympathetico-adrenal system ?

Options

A. Constriction of skin and visceral smooth muscle
B. Dilation of arterioles of heart and skeletal muscles
C. Constriction of puplis
D. Dilation of bronchioles

Answer

To determine which action is not produced by the sympathoadrenal system, we need to understand what actions are typically associated with this system. The sympathoadrenal system is a combination of the sympathetic nervous system and the adrenal glands, which release hormones like adrenaline (epinephrine) and noradrenaline (norepinephrine) during stressful situations, often referred to as the "fight or flight" response.

### Step-by-Step Solution:

1. **Understand the Sympathoadrenal System**:
- The sympathoadrenal system involves the sympathetic nervous system and the adrenal glands. It is activated in response to stress or danger.

2. **Identify the Key Hormones**:
- The primary hormones released by the adrenal glands during activation of this system are adrenaline and noradrenaline.

3. **List Actions Associated with the System**:
- Increased heart rate: The sympathetic system stimulates the heart to beat faster.
- Dilation of bronchioles: This allows more air to enter the lungs, facilitating increased oxygen intake.
- Constriction of blood vessels in non-essential areas (like skin and visceral organs) to redirect blood to vital organs (heart and brain).
- Dilation of arterioles in skeletal muscles: This ensures that muscles receive more blood and oxygen.

4. **Identify the Action Not Associated with the System**:
- Constriction of pupils: This is not an action produced by the sympathoadrenal system. In fact, during a stress response, pupils typically dilate to allow more light in for better vision.

5. **Conclusion**:
- The action that is not produced by the sympathoadrenal system is the constriction of pupils.

### Final Answer:
The action not produced by the sympathoadrenal system is **constriction of pupils**.

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