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Alveolar epithelial cells
Blood cells
Alveolar macrophages
Endothelial cells
Type II alveolar epithelial cells
Alveolar
Terminal saccular
Pseudoglandular
Canalicular
Embryonic
Occur regularly and continuously
Facilitate exchange of oxygen and carbon dioxide between mother and fetus
Decrease as the time of delivery approaches
Are essential for lung development
Prevent aspiration of amniotic fluid
Tracheal stenoisis
Tracheal atresia
Hyaline membrane disease
Duodenal atresia
Esophageal atresia with tracheoesophageal fistula
Splanchnic mesoderm
Neuroectoderm
Endoderm
Neural crest cells
Intermediate mesoderm
Tracheal ridges
Esophageal ridges
A gut septum derived from neural crest cells
Tracheoesophageal ridges
Laryngeal ridges
The canalicular period starts at 26 weeks
Surfactant is produced by type II pneumocytes during the pseudoglandular period
Over 600 million alveoli are present at birth
The blood:air barrier forms during the terminal saccular period
Respiratory epithelium is primarily pseudostratified squamous cuboidal
Terminal bronchioles will branch to give respiratory bronchioles
Secondary bronchi are also known as segmental bronchi
Two secondary bronchi develop on the right and three secondary bronchi develop on the left
A bronchopulmonary segment consists of only primary and secondary bronchi
Terminal bronchioles are also known as quaternary bronchi