Topics:
Animal Physiology, Animal Refresher
Hering-Breuer Reflex – Lung Protection
Reflexes that prevent over-dilation of lungs during inspiration and collapse of lungs during expiration are called:
- Haldane reflex
- Hering-Breuer reflex — Correct Answer
- Bohr reflex
- Bainbridge reflex
Explanation:
Correct Answer: Hering-Breuer reflex
The Hering-Breuer reflex (pulmonary stretch reflex) prevents over-dilation of lungs during inspiration and collapse during expiration, thus protecting lung tissue.
Mechanism
- Stretch receptors in the walls of bronchi and bronchioles are activated when lungs expand excessively.
- Signals travel via the Vagus nerve to respiratory centres → inhibit inspiration → trigger expiration.
- These are activated when lung volume is about 3 times the tidal volume.
Related Reflexes
- Bohr effect: Effect of CO₂ and H⁺ on the ability of Hb to bind/release O₂ (not a reflex).
- Haldane effect: Effect of O₂ on H⁺ and CO₂ loading and unloading from Hb (not a reflex).
- Bainbridge reflex: Increase in heart rate in response to increased venous return/atrial filling.
📚 About this Topic — Animal Physiology
This multiple choice question is from Animal Physiology, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Physiology to strengthen your preparation.
