Embryology Flashcards
Which germ layer gives rise to the lung bud and the lining of the respiratory tree?
Endoderm
Which germ layer gives rise to the smooth muscle, cartilage and blood supply of the respiratory tree?
Mesoderm
How do primary bronchial buds form?
Bifurcation of the trachea, producing the right and left bronchi
How do secondary bronchial buds form?
Bifurcation of right + left bronchi, producing 3 right lobar bronchi and 2 left lobar bronchi
Name the 5 stages of lung development (elephants play chess in sunny Africa…)
Embryonic Pseudoglandular Canalicular Saccular Alveolar
What happens in the embryonic phase of lung maturation?
Respiratory diverticulum forms off oesophagus
Initial branching produces lung, lobes + segments
What happens in the pseudoglandular phase of lung maturation?
Terminal bronchioles form
What happens in the canalicular phase of lung maturation?
Respiratory bronchioles form
What happens in the saccular phase of lung maturation?
Terminal sacs form (begin to form alveoli)
What happens in the alveolar phase of lung maturation?
Alveolar sacs mature