6.4 Gas Exchange

IB Assessment Statements
1. Distinguish between ventilation, gas exchange and cell respiration 

2. Explain the need for a ventilation system 

3. Describe the features of alveoli that adapt them to gas exchange 

4. Draw and label a diagram of the ventilation system, including trachea, lungs, bronchi, bronchioles and alveoli 

5. Explain the mechanism of ventilation of the lungs in terms of volume and pressure changes caused by the internal and external intercostal muscles, the diaphragm and abdominal muscles