AEMCA Practice Exam

What role does cranial nerve 10 play in the body?

1. Facilitates swallowing

2. Stimulates salivary glands

3. Activates muscles of the face

4. Regulates heart rate and gastrointestinal functions

The correct answer is: Regulates heart rate and gastrointestinal functions

Cranial nerve 10, also known as the vagus nerve, plays a critical role in regulating heart rate and gastrointestinal functions. It is a key component of the parasympathetic nervous system, which is responsible for promoting a "rest and digest" state in the body. The vagus nerve extends from the brainstem to various organs, including the heart, lungs, and digestive tract. In terms of heart regulation, the vagus nerve exerts an inhibitory effect on the heart by releasing neurotransmitters that decrease heart rate. This is essential for maintaining a balanced heart rhythm, especially after periods of physical exertion or stress. When it comes to gastrointestinal functions, the vagus nerve stimulates peristalsis (the wave-like movements that propel food through the digestive system) and regulates the secretion of digestive enzymes and gastric acids. This amplification of digestive activity is crucial for effective digestion and nutrient absorption. The other options, while important functions in their own right, do not directly correspond to the primary roles of cranial nerve 10. For instance, swallowing is primarily facilitated by cranial nerves 9 and 12, salivary gland stimulation is more associated with cranial nerves 7 and 9, and facial muscle activation is primarily