Development of the Respiratory system Flashcards
Which germ layer forms the epithelium of the whole respiratory passage
Endoderm
Which germ layer forms the cartilaginous, muscular & connective tissue components of the larynx, trachea, and lungs
Mesoderm
The respiratory system begins development during which week of embryonic development
Week 4
Which wall of the foregut does the respiratory diverticulum (lung bud) arise from
Ventral wall of the foregut
An increase n which chemical upregulates the transcription factor for lung bud development
Retinoic acid
Retinoic acid upregulates which transcription factor in lung development
TBX4
Which layer of the foregut is TBX4 (needed for lung development) expressed
Endoderm
During which weeks is the critical time for lung development
25-28th week
The tracheoesophageal septum divides the forgut into what ventrally and what dorsally
The trachea ventrally and the esophagus dorsally
Which structure allows for the communication between the lung bud and the pharynx
laryngeal orifice
The muscle and cartilage of the larynx is derived from which pharyngeal arch(es)
4th and 6th pharyngeal arch
Transformation of the 4th and 6th pharyngeal arches into which 3 cartilages form the adult shape of the larynx
Thyroid, cricoid and arytenoid cartilages
Three and false vocal cords originate from which embryonic structure
A pair if lateral ventricles
Improper formation of tracheoesophageal septum can result in which condition
Tracheoesophageal fistulas
What other two conditions result due to Tracheoesophageal fistulas
esophageal atresia & polyhydramnios
What can result due to esophageal atresia & polyhydramnio
excessive accumulation of saliva/ mucus in the nose and mouth, episodes of gaging, & cyanosis after swallowing milk, abdominal distension after crying, reflux of gastric contents into the lungs causes pneumonitis/pneumonia
At which week does the limb buds form the right and let main bronchi
5th week
Which layer of the lateral plate mesoderm forms –parietal layer of pleural cavity
Somatic layer
Which later of lateral plate mesoderm forms – visceral layer of pleura
Splanchnic layer
Which condition presents with a honeycomb appearance on a radiograph
• Congenital bronchial cysts (bronchiectasis)
What are the three period of lung maturation
Pseudo glandular period
Canalicular period
terminal sac period
alveolar period
Which type of alveolar epithelial cells secrete surfactant
Type II
babies born during which period of lung maturation cannot survive because respiration is impossible
pseudoglandular phase
How long does the Pseudo glandular period
last
5-16th week
How long does the Canalicular period last
16-26th week
How long does the Terminal sac period last
26th week to birth
How long does the Alveolar period last
8 month to childhood
When does surfactant increase the most during embryonic life
Last 2 weeks before birth
What is the function of surfactant
to prevent collapse of the alveoli
Growth of which 2 structures after birth is responsible for the increase in size of the lungs
respiratory bronchioles and alveoli
Absence of which substance leads to respiratory distress syndrome
surfactant
Which two substances can be given to increase production of surfactant
thyroxine and cortisol
The diaphragm develops during which weeks
5-6th week
The central tendon of the diaphragm comes form which embryological structure
septum transversum
The tendinous portion of the diaphragm comes form which embryological structure
Paired pleuroperitoneal membranes (somatic mesoderm)-
The crura of the diaphragm comes form which embryological structure
Dorsal mesentery of the esophagus
Myoblasts originating from somites at which cervical segments form the muscular components of the diaphragm
C3-C5
What causes Congenital diaphragmatic hernia
Failure of one /both pleuroperitoneal membranes to close the pericardioperitoneal canal
Herniation of abdominal contents into the thorax
Congentital diaphragmatic hernia are usually on which side of the body
left side
What causes esophageal hiatal hernia
Congential shortness f esophagus which leads to portions of the stomach being in the thorax
Pulomonary hypoplasia can be caused by which two conditions
Congenital diaphragmatic hernia
Bilateral renal agenesis
