Development of the Respiratory System Flashcards
When and where does the lung bud appear?
4th week
Ventral wall of the foregut
What are the three stages of foetal lung maturation?
Pseudoglandular
Cannicular
Saccular
What is meant by the pseudoglandular phase of lung development?
6-16 weeks
Divisions to form bronchopulmonary segments
What is meant by the canalicular phase of lung development?
16-26 weeks
Formation of respiratory bronchioles
What is meant by the saccular phase of lung development?
26 weeks onwards
Development of alveoli with type 1 and type 2 pneumocytes
What changes occur to type 1 pneumocytes?
Initially cuboidal but progressively thins with foetal maturation to become squamous. This process begins at 26 week of life
When do type 2 pneumocytes appear?
24 weeks gestation
The visceral pleura is derived from which embryological structure?
Splanchnic mesoderm
The parietal pleura is derived from which embryological structure?
Somatic mesoderm
When does the formation of definitive alveoli occur?
36 weeks onwards
Which structures contribute to the formation of the diaphragm?
Septum transversum
Mesentery of the oesophagus
Pleuroperitoneal membrane
Muscular growth from body wall
At how many weeks gestation do foetal breathing movements occur?
12 weeks
