Embryology 3 Flashcards
Where does the primitive oesophagus bud from?
foregut - laryngeotracheal groove
At what week does the primitive oesophagus bud?
week 4
Are the larynx and trachea anterior or posterior to the pharynx and oesophagus?
anterior
How does the trachea and lung buds form?
Diverticulum (endoderm) covered in mesoderm enlarges
What is the name of the septum which develops between the trachea and the oesophagus?
oesophagotracheal septum
What mesoderm does the visceral pleura form from?
splanchnic
What mesoderm does the parietal pleura form from?
somatic
What is a fistula?
An abnormal or surgically made passage involving hollow or tubular organs and sometimes the body surface
What is atresia?
Orifice or passage is closed or absent
Name the 3 periods in the differentiation of lung buds
embryonic
foetal
postnatal
When do the lung buds appear?
day 26 in the form of a respiratory diverticulum
How many components go on to make the diaphragm?
4
What does the central tendon form from?
septum transversum
What does the muscular part of the diaphragm arise from?
Pleuroparietal membrane
peripheral body wall muscle
What does the mesentery of the diaphragm go on to form?
Crura of diaphragm
What does the gut tube form from?
endoderm
When does the folding of the embryo occur?
week 3
What does the respiratory diverticulum create?
median trachea and two lateral pockets
Where does the respiratory diverticulum form?
ventral part of the digestive tract
Where do the pulmonary arteries individuate at?
6 aortic arch
What 3 stages make up the foetal period?
pseudoglandular
canalicular
saccular
What stage are the pneumocytes formed?
canalicular
What percentage of alveoli are formed postnatally?
95%
What is respiratory distress syndrome
A disease affecting around 2% of newborns where there is a deficiency in surfactant
