What combination of inspirations and expirations is needed to transport one pocket of air through the avian respiratory system?

Question

Quizplus · Accepted Answer

The avian respiratory system requires a unidirectional flow of air, meaning that air flows in one direction through the system, rather than in and out through the same pathway as in humans. This is achieved by a combination of inspirations and expirations. Birds have two cycles of inhalation and exhalation during the transport of one pocket of air, which is represented by choice B: 2 inhalations, 2 expirations.

What Combination of Inspirations and Expirations Is Needed to Transport