Excessive stimulation of vagus nerve in humans may lead to

Options

A. Hoarse voice
B. Peptic ulcer
C. Efficient digestion of proteins
D. Irregular contraction of diaphragm

Answer

**Step-by-Step Solution:**

1. **Understanding the Vagus Nerve**: The vagus nerve is a crucial part of the autonomic nervous system. It is responsible for various functions including heart rate regulation, digestion, and sensory information from the throat, heart, lungs, and abdomen.

2. **Effects of Vagus Nerve Stimulation**: When the vagus nerve is stimulated, it can lead to a state of relaxation in the body. However, excessive stimulation can have negative effects.

3. **Analyzing the Options**:
- **Option 1: Hoarse Voice**: While hoarseness can be a side effect of vagus nerve stimulation, it is not the primary consequence of excessive stimulation. Thus, this option is incorrect.
- **Option 2: Peptic Ulcer**: Excessive stimulation of the vagus nerve can lead to increased gastric acid secretion. This overproduction can damage the stomach lining, resulting in peptic ulcers. Therefore, this option is correct.
- **Option 3: Efficient Digestion of Proteins**: Although the vagus nerve aids in digestion, its overstimulation does not enhance the efficiency of protein digestion. Hence, this option is incorrect.
- **Option 4: Irregular Contraction of Diaphragm**: This option is not directly related to the effects of vagus nerve stimulation and is therefore incorrect.

4. **Conclusion**: After analyzing all the options, the correct answer is **Option 2: Peptic Ulcer**. Excessive stimulation of the vagus nerve can lead to increased gastric acid secretion, which can cause damage to the stomach lining and result in peptic ulcers.

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