Question

The Hering-Breuer reflex

A) alters pulmonary ventilation when the PCO2 changes.
B) functions to increase ventilation with changes in blood pressure.
C) alters pulmonary ventilation when the PO2 changes.
D) is an important aspect of normal, quiet breathing.
E) prevents over expansion of the lungs.

Answer 1

The Hering-Breuer reflex prevents over-expansion of the lungs by inhibiting inspiration when stretch receptors in the lung walls are activated, thus contributing to the regular rhythm of quiet breathing. The correct answer is option E).

Step-by-step explanation:

The question refers to the Hering-Breuer reflex, which is a physiological mechanism that plays a role in respiratory functions. The correct answer to the student's question, which asks for the role of the Hering-Breuer reflex, is option E: It prevents over expansion of the lungs. The reflex is triggered when stretch receptors in the walls of the lungs are activated as the lungs inflate. This reflex mechanism helps to protect the lungs from over-inflation by inhibiting further inspiration, thus playing a crucial role in regulating the rhythm of quiet breathing. It is not directly involved in the responses to changes in PCO2, PO2, or blood pressure in the context of the options provided.