Embryo- Development of the RS Flashcards
During what week does the development of the Respiratory System commence?
During week 4(4th week of development)
The development of the Respiratory System starts with the development of ….
Lung Bud
Lung Bud or Respiratory Diverticulum
what is it?
is an outgrowth of the ventral wall of the FOREGUT portion of the digestive tract
Lung bud is dependent on the increase of what?
increase of Retonic Acid(RA) produced by the MESODERM
RA(Retonic Acid) causes the upregulation of…
TBX4 which will be expressed on the endoderm of the gut tube
thus… inducing the formation of the LUNG BUD
Lung Bud will turn into lower respiratory structures like?
Trachea
Larynx
Lungs
Bronchi
Epithelium of internal lining of the Trachea, Larynx,Bronchi and Lungs will be made out of ?
Endoderm (Endodermal origin)
What is the cartilageoneous,muscular and connectie tissue components of the Trachea and Lungs made of?
Visceral (Splanchnic) Mesoderm that surrounds the foregut
How is the Lung Bud and the Foregut separated ?
or
How is the intial open communication of the Lung Bud and the Foregut closed up?
by the Tracheoesophageal Ridges
When Tracheoesophageal Ridges fuse and they form…
Tracheoesophageal Septum
which..
divides the foregut into:
Dorsal portion( esophagus)
Ventral portion( trachea and lung buds)
Esophageal Atresia
caused by an abnormal separation of the esophagus and the trachea
(So they can be connected,which is NOT NORMAL)
Tracheoesophageal Fistula
abnormal connection/hole between trachea and esophagus
Type C: Most common. Portion of the esophagus did not develop and produces pouch. lower esophagus connects directly to the trachea
Type D: Portion of the esophagus did not develop and produces pouch. Pouch and lower esophagus connects through the trachea
Internal linning of the larynx originates from…
Endoderm
Larynx forms into….how many arches?
6 pharyngeal arches
* Each arch made out of mesenchyme
Mesenchyme proliferates rapidly… which causes?
laryngeal orifice to change appearance from a sagittal slit into a T shape opening
T shape opening= leads to larynx formation