What is one of the main functions of the vagus nerve in the body?

• A. It regulates body temperature
• B. It controls heart rate
• C. It produces hormones
• D. It facilitates oxygen transport

Answer: (B)

The vagus nerve plays a crucial role in the autonomic nervous system, particularly in regulating involuntary functions of the body. One of its primary functions is the control of heart rate. It operates predominantly through the parasympathetic nervous system, which helps to slow down the heart rate and promote a state of relaxation and recovery after stress. The vagus nerve achieves this by releasing neurotransmitters that act on the heart, reducing the rate at which the heart beats and contributing to the overall modulation of cardiovascular function.

In contrast, the other options do not accurately reflect the primary roles of the vagus nerve. Body temperature regulation involves the hypothalamus and is not directly managed by the vagus nerve, hormone production is primarily the function of endocrine glands rather than a nerve, and oxygen transport is mainly the role of the circulatory system facilitated by the blood and respiratory systems. Therefore, the regulation of heart rate is the most appropriate answer when considering the main functions of the vagus nerve.