Development Of The Foregut Flashcards
Where does the foregut start and end?
Distal oesophagus
To
Halfway along the duodenum (1st and 2nd parts of the duodenum are foregut)
Where does the midgut start and end?
Halfway along the duodenum (just distal to the entrance of the bile duct – 3rd and 4th parts of duodenum are midgut)
To
Junction of the proximal 2/3 of the transverse colon with the proximal 1/3 (first 2/3 of the transverse colon are midgut)
Where does the hindgut start and end?
Distal 1/3 of the transverse colon
To
Upper anal canal
What is the arterial supply of the foregut?
Coeliac trunk
What is the sympathetic and parasympathetic innervation for the foregut?
S: Greater splanchnic n. (T5 – T9)
P: Vagus
Where is visceral pain of the foregut felt?
Epigastric region
What is the arterial supply of the midgut?
Superior mesenteric artery
What is the sympathetic and parasympathetic innervation for the midgut?
S: Lesser splanchnic n. (T10-11)
P: Vagus
Where is visceral pain of the midgut felt?
Umbilical region
What is the arterial supply of the hindgut?
Inferior mesenteric artery
What is the sympathetic and parasympathetic innervation for the hindgut?
S: Least splanchnic n. (T12 +/- L1) and lumbar splanchnic nerves
P: Pelvic splanchnics
Where is visceral pain of the hindgut felt?
Suprapubic region
What does the bilaminar disc develop from?
Develops from the inner cell mass
What happens in gastrulation?
Primitive streak forms on the epiblast
Epiblast cells migrate to the primitive streak and invaginate through it
Some cells displace the hypoblast and form the endoderm
Some cells create a new layer between the epiblast and endoderm = mesoderm
Epiblast = ectoderm
What does the ectoderm layer give rise to?
CNS and PNS
Skin, hair and nails
Pituitary gland, sweat glands, tooth enamel
What does the mesoderm layer give rise to?
Muscle, cartilage and bone
Urogenital system, spleen and adrenal cortex
Connective tissue of the gut wall, pancreas and liver
Visceral peritoneum
What does the endoderm layer give rise to?
Epithelium of the GI tract, respiratory tract
Hepatocytes (cells of the liver)
Endocrine and exocrine cells of the pancreas
What does inner cell mass develop into?
Human beings
What does outer cell mass develop into?
Placenta
What can failure of closure of the ventral body wall in the thoracic region lead to?
Ectopia cordis
What can failure of closure of the ventral body wall in the abdomen lead to?
Gastroschisis
What can failure of closure of the ventral body wall in the pelvic region lead to?
Bladder exstrophy
What does the foregut develop into?
Oesophagus
Stomach
First half of the duodenum (1st and 2nd parts)
What are the derivatives of the foregut?
Liver
Pancreas