Embryology (respiratory and cardiovascular) Flashcards
What does the respiratory system form from?
The endoderm?
What week period is the embryonic stage?
Weeks 3-8
What does the lung bud form from?
Forgut
What happens during the embryonic phase?
Formation of the trachea and the primary lung buds
What week is pseudoglandular stage?
5-17 weeks
What happens during the pseudoglandular stage?
The airway disvision is complete and the trachea and main bronchi are formed
When does the canalicular stage take place?
During weeks 16 - 26
What happens during the cannalicular stage?
Capillarisation with the formation of acinus (terrminal brochioles)
Gas exchnage is made possible
Type I and II pneumocytes start differentiating
What week period is the saccular stage?
24 - 38 weeks
What happens during the saccular stage?
The type I pneumocytes start thining, the type II pneumocytes produce surfactant.
Sacs move from the terminal bronchioles to the respiratory bronchioles.
When is the alveolar stage?
Weeks 36 to infancy
What happens in the alveolar stage?
Formation of the true alveoli.
What does the endothelial lining of the larynx come from?
Endoderm of laryngotracheal tube.
Where does the cartilage of the trachea come from?
4th and 6th laryngeal arches
Where does the epiglottis come from
caudal part of hypopharyngeal eminence
