1. Figure 49.2 The Double Bind of Water Breathers

2. Figure 49.3 Gas Exchange Systems

3. Figure 49.5 Fish Gills

4. Figure 49.5 Fish Gills (Part 2)

5. Figure 49.6 Countercurrent Exchange Is More Efficient

6. Figure 49.9 Measuring Lung Ventilation

7. Figure 49.10 The Human Respiratory System (Part 1)

8. Figure 49.10 The Human Respiratory System (Part 2)

9. Figure 49.12 Binding of O 2 to Hemoglobin Depends on P O 2

11. Figure 49.13 Oxygen-Binding Adaptations

12. Figure 49.14 Carbon Dioxide Is Transported as Bicarbonate Ions

13. Figure 49.14 Carbon Dioxide Is Transported as Bicarbonate Ions (Part 1)

14. Figure 49.15 Breathing Is Controlled in the Brainstem

15. Figure 49.16 Carbon Dioxide Affects Breathing Rate

16. Figure 49.18 Feedback Information Controls Breathing

17. LE 42-29a O 2 unloaded from hemoglobin during normal metabolism O 2 reserve that can be unloaded from hemoglobin to tissues with high metabolism P and hemoglobin dissociation at 37°C and pH 7.4 O2O2 P (mm Hg) O2O2 Tissues during exercise Tissues at rest Lungs 10080 6040200 0 40 60 80 100 O 2 saturation of hemoglobin (%)

18. LE 42-29b Bohr shift: additional O 2 released from hemoglobin at lower pH (higher CO 2 concentration) pH and hemoglobin dissociation P (mm Hg) O2O2 10080 6040200 0 40 60 80 100 O 2 saturation of hemoglobin (%) pH 7.2 pH 7.4