Chapter 29, Problem 14STP

Summary Introduction

To write:

The reason that the birds need an efficient respiratory system.

Introduction:

Birds belong to the Aves class and contain nearly 8,600 species, making them the most abundant of all terrestrial vertebrates. Birds vary in size from tiny hummingbirds flying over bright flowers to massive ostriches racing across the African plains. Birds are present in deserts, forests , mountains, prairies and all seas. Birds have wings, lightweight bones, feathers, and other adaptations that allow for flight.

Explanation of Solution

In birds, flight muscles require a significant amount of oxygen and bird's respiratory systems are well equipped to provide it. Not only do birds have much more air space in their respiratory system than reptiles, but birds also have one-way air circulation. When the bird inhales oxygenated air, it travels through the trachea to the back air bags. Other air already within the respiratory system is pulled out of the lungs, where gas is transferred, and into the anterior air bags. When the bird exhales, the deoxygenated air in the anterior air bags is removed from the respiratory system, and the oxygenated air from the posterior air bags is sent to the lungs. The overall outcome is that only oxygenated air passes into the lungs and flows in a single direction compared to the flow of blood.

Conclusion

Thus, birds need an effective respiratory system because they need energy bursts at times during flight.