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Pulmonary capillaries
Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. 1000x
![Lumen of alveolar duct <p>Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. 1000x </p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.B.PC_.01.P01-1.png)
Lumen of alveolar duct
Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. 1000x
![Alveolar lumens <p>Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. 1000x </p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.B.PC_.01.P02-1.png)
Alveolar lumens
Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. 1000x
![Pulmonary capillaries > <p>Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. Red arrows indicate a capillary cut in longitudinal section. 1000x </p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.B.PC_.01.P03-1.png)
Pulmonary capillaries >
Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. Red arrows indicate a capillary cut in longitudinal section. 1000x
![Interalveolar septum <p>Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. 1000x </p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.B.PC_.01.P04.png)
Interalveolar septum
Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. 1000x
![Air-blood barrier <p>Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. 1000x </p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.B.PC_.01.P05.png)
Air-blood barrier
Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. 1000x
![Endothelial cell nuclei <p>Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. 1000x </p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.B.PC_.01.P06.png)
Endothelial cell nuclei
Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. 1000x
![Type I cell <p>Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. 1000x </p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.B.PC_.01.P07.png)
Type I cell
Deoxygenated blood from the pulmonary arteries supplies the pulmonary capillaries in the interalveolar septa. The walls of these capillaries form a portion of the air-blood barrier, across which oxygen and carbon dioxide are transported. Pulmonary capillaries drain into pulmonary veins. 1000x