Airway branching Name DIvision Diameter(mm) How many? Cross-sectional Trachea 15-22 2.5 Primary bronchi 012345 10-15 E$0 Smaller 太然N bronchi 110 iE 6-11 1X10 2x104 100 Bronchioles 12-23 8x107 5X10 Alveoli 24 0.3 3-6x10 >1X10 6
11 Airway branching
Section‖ BLOOD SUPPN TO THE LUNG Two separate blood supplies: pulmonary circulation and bronchial circulation Pulmonary circulation Respiratory epithelium Bronchial circulation ven chis ng ion. Capillary
12 Section II BLOOD SUPPLY TO THE LUNG • Two separate blood supplies: pulmonary circulation and bronchial circulation • Pulmonary circulation • Bronchial circulation
Pulmonary circulation ventricle to the gas-exchange unit er Brings deoxygenated blood from the right At the gas-exchanging units oxygen is picked up and carbon dioxide is removed from the blood The oxygenated blood returned to the left atrium for distribution to the rest of the body 13
13 Pulmonary circulation • Brings deoxygenated blood from the right ventricle to the gas-exchange units • At the gas-exchanging units, oxygen is picked up and carbon dioxide is removed from the blood • The oxygenated blood returned to the left atrium for distribution to the rest of the body
Bronchial circulation Arise from the aorta Provides nourishments to the lung parenchyma(肺实质) Bronchiole nary artery Branch Iveolnr sac Visceral pleura Parietal pleura
14 Bronchial circulation • Arise from the aorta • Provides nourishments to the lung parenchyma（肺实质）