Embryology- development of respiratory system Flashcards
from what part of the primitive gut tube does the rest system develop
foregut part
what when and where does the first structure form
at 4 weeks, lung bud comes out from wall of foregut anterior to oesophagus. septum comes between them and separates the pharynx from trachea. lung buds enlarge to form lungs
what if trachea and oesophagus don’t separate
tracheoesphageal fistula (abnormal passage) and oesophageal atresia (closed off passage). they can be separated surgically
what mesoderm becomes visceral pleura
splanchnic
what mesoderm becomes parietal pleura
somatic
how are plurae formed
lung buds will push the splanchnic mesoderm towards the somatic mesoderm and become completely surrounded by both layers and the space between the two layers is the pleural cavity
what is pleural cavity Called before it is closed off from the heart and the abdomen
pericardioperitoneal canal
how do the pleural cavities get closed off from the heart
pleuropericardial fold grows from somatic mesoderm and closes off the pleural cavity from the heart. this eventually becomes pericardium of the heart
how do the pleural cavities get closed off from the abdomen
diaphragm grown from mesoderm
stages of lung growth
embryonic, pseudoglandular, canilcular, saccular, alveolar
neonatal respiratory distress syndrome
surfactant deficiency, partial collapse of alveoli
lung agenesis
one lung. caused by failure of lung bud to develop on one side, insufficient mesoderm, teratogens (poisons)
4 mesodermal structures that diaphragm develops from
septum tranversum, pleuroperitoneal membrane, oesophagus mesentery, muscular ingrowth from body wall
defects in diaphragm development
hernia, pulmonary hypoplasia
