All of the following are under regulation of sympathetic and parasympathetic nervous systems except

Options

A. Heart rate
B. Digestive tract activity
C. Learning
D. Micturition

Answer

To solve the question, we need to identify which of the options provided is not regulated by the sympathetic and parasympathetic nervous systems. Let's analyze each option step by step.

### Step 1: Analyze Heart Rate
- The sympathetic nervous system increases heart rate by releasing catecholamines (epinephrine and norepinephrine).
- The parasympathetic nervous system decreases heart rate by releasing acetylcholine.
- **Conclusion**: Heart rate is regulated by both systems.

### Step 2: Analyze Digestive Tract Activity
- The sympathetic nervous system inhibits gastrointestinal secretions and slows down digestion.
- The parasympathetic nervous system stimulates digestive secretions and promotes digestion.
- **Conclusion**: Digestive tract activity is regulated by both systems.

### Step 3: Analyze Learning
- Learning is a cognitive function that is primarily regulated by higher brain functions and is not directly controlled by the sympathetic or parasympathetic nervous systems.
- **Conclusion**: Learning is not regulated by either system.

### Step 4: Analyze Micturition (Urination)
- The sympathetic nervous system inhibits micturition.
- The parasympathetic nervous system stimulates bladder contraction and promotes urination.
- **Conclusion**: Micturition is regulated by both systems.

### Final Conclusion
Based on the analysis, the option that is not under the regulation of the sympathetic and parasympathetic nervous systems is **Learning**.

### Answer
**Learning** is the correct answer as it is not regulated by the sympathetic and parasympathetic nervous systems.

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