- 1- Gas exchange in humans involves breathing, transport of gases, and exchange with body cells
- 2- Animals exchange O2 and CO2 across moist body surfaces
- 3- visualizing the concept: Gills are adapted for gas exchange in aquatic environments
- 4- The tracheal system of insects provides direct exchange between the air and body cells
- 5- Evolution Connection: The evolution of lungs facilitated the movement of tetrapods onto land