Which mechanism prevents over-inflation of the lungs during normal respiration?

The mechanism that prevents over-inflation of the lungs during normal respiration involves stretch receptors. These specialized nerve endings are located within the walls of the bronchi and bronchioles. When the lungs fill with air during inhalation, the stretch receptors are activated by the expansion of lung tissue.

Once these receptors are stimulated, they send signals to the brain that help regulate the respiratory rate and depth. This feedback mechanism essentially prevents the lungs from becoming overly inflated by triggering the Hering-Breuer reflex, which signals the respiratory centers to stop inhalation and initiate exhalation when certain lung volume thresholds are reached. This protective mechanism helps maintain normal lung function and protects against potential damage from excessive stretching, ensuring that respiration remains efficient and safe.