PATHOLOGY

Detailed explanation-1: -Inhale: Air flows through the nostrils, into the trachea, and fills the posterior air sacs. Exhale: Air exits the posterior air sacs and flows into the lungs. (In the lungs, the gas exchange takes place, swapping carbon dioxide for fresh oxygen.) Inhale: Air exits the lungs and flows into the anterior air sacs.

Detailed explanation-2: -Lungs have air sacs connected and supplement respiration. The air sacs are hollow bones that allow gases to flow around the body. The lungs of birds do not inflate or deflate. But the lungs maintain a constant volume.