Final answer:
The Hering-Breuer reflex serves to terminate inhalation and prevent lung overexpansion by activating inhibitory signals that stop the inspiratory muscles once the lungs have expanded adequately.
Step-by-step explanation:
The Hering-Breuer reflex is an important physiological mechanism within the respiratory system, responsible for protecting the lungs from excess inflation. This reflex is triggered when stretch receptors within the walls of the lungs become activated as the lungs expand during inhalation. The activation of these receptors sends inhibitory signals via the vagus nerve to the respiratory centers of the brain, specifically to the medulla oblongata, signaling it to cease the activation of the inspiratory muscles. As a result, this reflex leads to the termination of inhalation, preventing lung overexpansion and potential damage from occurring.
Looking at the provided options, the correct answer would be (1) terminates inhalation and prevents lung overexpansion because the primary purpose of the Hering-Breuer reflex is to regulate the level of lung inflation, inhibiting further inspiration when the lungs are sufficiently expanded. This protective mechanism ensures that the delicate tissues of the lungs are safeguarded from the stress and potential trauma of overinflation during breathing, particularly during vigorous respiratory activity such as during exercise or when the body has an increased demand for oxygen.