Development of GI and Respiratory Flashcards
pharyngeal pouches form
tonsils and auditory tube
pharynx is initially closed by what?
oropharyngeal membrane
skeletal muscle of esophagus/pharynx is derived from what?
somites that migrate to pharyngeal arches IV and VI
splanchnic mesoderm forms what components of digestive tract
smooth muscle and connective tissue components of digestive tract
splanchnopleure forms what three divisions of digestive tract
foregut, midgut (yolk sac) and hind gut
endoderm becomes what part of digestive tract
epithelial lining
the hindgut terminates in a ____
cloaca
The cloaca communicates with what systems?
digestive, urinary, and genital systems
proctodeum
from hindgut –> caudal part of anal canal, it’s a depression formed by extension of ectoderm from anal membrane. caudal anal canal is surrounded by stratified squamous epithelium…proctodeum gets incorporated into anal canal when anal membrane recedes. in carnivores, lateral diverticula of proctodeum ectoderm become ANAL SACS
anal sacs are formed from
lateral diverticula of proctodeum ectoderm.
hepatic diverticulum
the outcropping of endoderm from foregut that becomes liver. the non-outcropped part will become descending duodenum. becomes hepatic ducts, cystic duct and pancreatic duct.
epithelium of nasal cavity is formed from what germ layer?
ectoderm. the rest of the respiratory epithelium is endoderm!
larynx formation
splanchnic mesoderm of pharyngeal arch forms bilateral laryngeal swellings and rostral epiglottal swelling
blind end of caudal trachea becomes:
bronchial buds –> principal bronchi –> lobar bronchi –> segmental bronchi –> bronchioles –> terminal sacs and alveoli
endoderm-lined bronchial tree grows into what type of germ layer?
splanchnic mesoderm, which forms CT, smooth muscle, vessels and cartilage of lung.
