Embryology Flashcards
What part of gut tube do the lung buds sprout from
Upper gut tube, around the oesophagus
What is the connection between respiratory and digestive tract in adults
Pharynx
Process of formation of lung buds
As the oesophagus lengthens, a respiratory diverticulum forms along with a tracheoesphageal ridge. This respiratory diverticulum grows into the lung buds whereas the tracheosophageal ridge seperates the trachea and oesophagus
Respiratory congenital defects
Oesophageal atresia (blind-ending) and tracheoesophageal fistula (communication)
What can trancheosophageal fistula cause
Abnormal connection which causes ingested food to enter respiratory tract - infection prone
What arises from the endoderm and mesoderm
Tubular ventral growth from foregut phrynx - Foregut
Mesenchyme of lung buds - Mesoderm
How do the alveoli develop
The respiratory bronchioles start off with cuboidal epithelium cells. These develop to thin squamous cells to form a more efficient blood-air barrier. Blood capillaries establish close contact with these thin squamous cells via their flat endothelium
What pneumocytes produce surfactant and lack of this can cause?
Alveolar type 2 cells produce surfactant. Lack of pulmonary surfactant production can cause structural immunity in the lungs - Infant Respiratory Distress Syndrome (IRDS)