Development Flashcards
Lower respiratory tract not completed until
End of fetal period
What forms the respiratory diverticulum
Anterior wall of foregut
Epithelium of internal respiratory system formed from
Endoderm
Cartilage, CT, SM of respiratory system formed from
Mesoderm
Into what does respiratory diverticulum divide
Lung buds
Division of trachea and esophagus through
Tracheoesophageal septum
Defect in tracheoesophageal septum results in
Trachea-esophageal fistulas
What is a tracheoesophageal fistula
Connection between trachea and esopagus
Cause of tracheaesophageal fistula
Mesoderm defect. Because mesoderm –> cartilage, CT, SM
VATER
Vertebral anomalies - Anal atresia - Tracheoesophageal fistula - Esophagus atresia - Renal atresia
VATERL
VATER + Limb diseases
When does septum transversum appear
4th week
Septum transversum at week 4
C1
Septum transversum at week 8
T7 and T12
Phrenic nerve root
C3-C5
Septumtransversum openings
Pericardioperitoneal openings at sides
What closes pericardioperitoneal openings at sides
Pleuroperitoneal membrane
Congenital diaphragmatic hernias
Hole on the sides of diaphragm because pleuroperitoneal membranes fail to close pericardioperitoneal spaces
What separates pleural and pericardial cavities
Pleuropericardial folds
When will trachea divide into 2 lung puds
5th week
Division of left primary bronchus into
2 secondary bronchi (lobes)
Division of right primary bronchus into
3 secondary bronchi (lobes)
When are tertiary bronchi (segmental bronchi) formed
7th week
How many segmental bronchi on left
10
How many segmental bronchi on right
8
Fibroblast growth factor involved in separating bronchi
FGF2 and FGF10
Development starts at week
4
