| Generation (G) | Number (n) | Length (mm) | Mean diameter (mm) | Re |
Trachea | 0 | 1 | 120.00 | 18.00 | 1480 |
Main Bronchus | 1 | 2 | 47.60 | 12.20 | 1092 |
Lobar Bronchus | 2 | 4 | 19.00 | 8.30 | 803 |
3 | 8 | 7.60 | 5.60 | 595 | |
Segmental Bronchus | 4 | 16 | 12.70 | 4.50 | 370 |
Bronchi w/Cartilage in Wall | 5 | 32 | 10.70 | 3.50 | 238 |
6 | 64 | 9.00 | 2.80 | 149 | |
7 | 128 | 7.60 | 2.30 | 91 | |
8 | 256 | 6.40 | 1.96 | 53 | |
9 | 512 | 5.40 | 1.54 | 34 | |
10 | 1024 | 4.60 | 1.30 | 20 | |
Terminal Bronchus | 11 | 2048 | 3.90 | 1.09 | 12 |
Bronchiole w/muscle in wall | 12 | 4096 | 3.30 | 0.96 | 6.78 |
13 | 8192 | 2.70 | 0.82 | 3.97 | |
14 | 16,384 | 2.30 | 0.74 | 2.20 | |
15 | 32,768 | 2.00 | 0.66 | 1.23 | |
Terminal Bronchiole | 16 | 65,536 | 1.65 | 0.60 | 0.68 |
Respiratory Bronchiole | 17 | 131,072 | 1.41 | 0.54 | 0.38 |
18 | 262,144 | 1.17 | 0.50 | 0.20 | |
19 | 524,288 | 0.99 | 0.47 | 0.11 | |
Alveolar Duct | 20 | 1,048,576 | 0.83 | 0.45 | 0.056 |
21 | 2,097,152 | 0.70 | 0.43 | 0.030 | |
22 | 4,194,304 | 0.59 | 0.41 | 0.015 | |
Alveolar Sac | 23 | 8,388,608 | 0.50 | 0.41 | 0.008 |
Alveoli. 21 Per duct |
| 3E+0 | 0.23 | 0.28 |
|