Erection of penis occurs due to :-

Options

A. Sympathetic nervous system
B. Parasympathetic nervous system
C. Both (1) and (2)
D. Cerebral cortex `to` ANS `to` vasodilation

Answer

**Step-by-Step Solution:**

1. **Understanding Erection Mechanism**: The erection of the penis is primarily a physiological process that involves the nervous system and blood flow.

2. **Role of the Nervous System**: The process of erection is controlled by the autonomic nervous system, which has two branches: the sympathetic and the parasympathetic nervous systems.

3. **Sympathetic vs. Parasympathetic Nervous System**:
- The sympathetic nervous system is responsible for the 'fight or flight' response and generally inhibits erection.
- The parasympathetic nervous system, on the other hand, is responsible for 'rest and digest' functions and plays a crucial role in facilitating erection.

4. **Vasodilation and Blood Flow**: During sexual arousal, the parasympathetic nervous system triggers vasodilation (widening of blood vessels) in the penile arteries, leading to increased blood flow to the penis.

5. **Conclusion**: Therefore, the erection of the penis occurs primarily due to the action of the parasympathetic nervous system, which promotes vasodilation and increased blood flow.

**Final Answer**: Erection of the penis occurs due to the parasympathetic nervous system.

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