Pharynx | | Volume | ↓ | Rib cage | |
Cross-sectional area | ↓ | Total alveolar number | ↓ | Cross-sectional area | ↓ |
Resistance | ↓ | Alveolar surface area | ↓ | Antero–posterior diameter | ↓ |
Patency | ↑ | Alveolar number per unit area | ≈ | Lateral diameter | ↓ |
Larynx | | Alveolar number per unit volume | ≈ | Thoracic index# | ≈ |
Glottis cross-sectional area | ≈ | Shape | ↓ pyramidal | Perimeter | ↓ |
Absolute dimension | ↓ | | | Volume (absolute) | ↓ |
Thyroid cartilage angle | ↑ | | | Volume (% chest wall volume) | ≈ |
Trachea | | | | Ribs inclination | ↑ |
Cross-sectional area (absolute) | ↓ | | | Ribs movement | ↑ pump-handle |
Cross-sectional area (standardised for lung size) | ≈ | | | Diaphragm | |
| | | | Total length | ↓ |
| | | | Length in the zone of apposition | ↓ |
| | | | Dome-shape factor on lateral projection | ↑ |
| | | | Dome-shape factor on antero–posterior projection | ≈ |
| | | | Height of the dome | ≈ |