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Pulmonary capillaries
Pulmonary capillaries, supplied by the pulmonary artery, protrude from the interalveolar septa into alveoli, thus maximizing the surface area across which gas exchange can occur. 1000x, 4000x
![Alveoli <p>Pulmonary capillaries, supplied by the pulmonary artery, protrude from the interalveolar septa into alveoli, thus maximizing the surface area across which gas exchange can occur. 1000x, 4000x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.B.PC_.02.P01.png)
Alveoli
Pulmonary capillaries, supplied by the pulmonary artery, protrude from the interalveolar septa into alveoli, thus maximizing the surface area across which gas exchange can occur. 1000x, 4000x
![Interalveolar septa <p>Pulmonary capillaries, supplied by the pulmonary artery, protrude from the interalveolar septa into alveoli, thus maximizing the surface area across which gas exchange can occur. 1000x, 4000x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.B.PC_.02.P02.png)
Interalveolar septa
Pulmonary capillaries, supplied by the pulmonary artery, protrude from the interalveolar septa into alveoli, thus maximizing the surface area across which gas exchange can occur. 1000x, 4000x
![Pulmonary capillaries <p>Pulmonary capillaries, supplied by the pulmonary artery, protrude from the interalveolar septa into alveoli, thus maximizing the surface area across which gas exchange can occur. 1000x, 4000x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.B.PC_.02.P03.png)
Pulmonary capillaries
Pulmonary capillaries, supplied by the pulmonary artery, protrude from the interalveolar septa into alveoli, thus maximizing the surface area across which gas exchange can occur. 1000x, 4000x
![Air-blood barrier <p>Pulmonary capillaries, supplied by the pulmonary artery, protrude from the interalveolar septa into alveoli, thus maximizing the surface area across which gas exchange can occur. 1000x, 4000x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.B.PC_.02.P04.png)
Air-blood barrier
Pulmonary capillaries, supplied by the pulmonary artery, protrude from the interalveolar septa into alveoli, thus maximizing the surface area across which gas exchange can occur. 1000x, 4000x