Q6 - Comparing Gas Exchange Strategies Across Animal Groups
The gas exchange surfaces, and the direction of respiratory-medium and blood flow, of different animals are sketched. Mammals and birds must use respiratory muscles to drive air to these surfaces, as shown.
Using the information and data, determine which of the statements are true or which are false.
A. Mammals require passive diffusion to exchange gases.
B. Mammals extract a greater proportion of the air’s oxygen than fish extract from water.
C. Air must reach within micrometers of active insect cells.
D. Bird lungs exchange gas with air for a greater proportion of a breathing cycle than mammals.
Question reproduced from IBO 2017, Theoretical Exam B, licensed under CC BY-NC-SA 4.0 - attributed to the International Biology Olympiad. Open the full exam PDF · Official answer key & worked solutions