128b - GI Development and Organization Flashcards
Which embryologic structure persists to form Meckel’s Diverticulum?
Yolk Sac
What is a primarily retroperitoneal organ?
Which organs are primarily retroperitoneal? (6)
Organs that start growing in the body wall behind the parietal peritoneum and remain there
- IVC
- Vagina
- Kidneys
- Aorta
- Rectum
- Bladder
If you were stuck outside all day you would need energy - maybe IV KARBs would help
In which part of the GI tract does a Meckel diverticulum form?
Terminal ileum
Which embryologic structure separates the pericardial/thoracic cavity from the peritoneal cavity?
Septum transversum
Which structure connects the lesser sac and the greater sac (peritoneal cavity)?
Epiploic foramen (of Winslow) aka Omental foramen
(Right behind the hepatoduodenal ligament)
Which structures arise from the ventral mesogastrium?
- Falciform ligament
- Lesser omentum
- Hepatogastric ligamnet
- Hepatoduodenal ligament
- Coronary ligament
If you were inside the lesser peritoneal sac or its entryway through the epiploic foramen, which of the following mesenteries would you be unable to touch?
A. Splenorenal
B. Prenicocllic
C. Hepatoduodenal
D. Gastrosplenic
E. Hepatogastric
B. Prenicocllic
What is the location of the junction of the abdominal foregut and midgut?
Middle of the duodenum
- Foregut
- End of the esophagus through the proximal 1/2 of the duodenum
- Midgut
- Distal duodenum through through the proximal 2/3 of the transverse colon
- Hindgut
- Distal 1/3 of the transverse colon through the pectinate line
Which congenital hernia is the result of an abdominal wall defect?
Gastroschisis
What birth defect arises from failure of the midgut to return to the abdominal cavity from the umbilical cord?
When is it supposed to return?
Omphaocele (congential umbilical hernia, covered by amnion)
Midgut should return by week 10
Failure = omphalocele
Which mesenteries form the lesser omentum?
Hepatogastric + hepatoduodenal ligaments
Which parts of the colon are peritonealized?
Which are retroperitoneal?
- Peritonealized
- Cecum, transverse colon, sigmoid colon -> upper 1/3 of rectum
- Retroperitoneal:
- Ascending colon, descending colon
Where in the abdominal cavity is the lesser sac located? (general)
The lesser sac is the “space behind the stomach”
It will grow down to cover the small intestines
Communicates wtih the greater sac through the epiploic/omental foramen (behind the hepatoduodenal ligament)
Which major artery supplies the midgut?
Superior mesenteric artery
What is a secondarily retroperitoneal organ?
Which organs are secondarily retroperitoneal? (4)
Organs that begin growing in the mesentery, but get pushed against the body wall (and stick there) by the growth of peritoneal organs, so they look retroperitoneal
- Pancreas
- Ascending colon
- Descending colon
- Duodenum
They’re pushed agsinst the body wall, covering it like a PADD
Which anatomic features that distinguish large intestine from small intestine?
Teniae coli and Haustra in the large intestine
What is a peritonealized organ?
Which organs are peritonealized? (9)
Organs that develop in mesenteries and hang out inside of the peritoneum
- Stomach
- Liver
- Uterus
- Gallbladder
- Spleen
- Intestines (except duodenum)
- Cecum
- Transverse colon
- Sigmoid colon -> upper 1/3 of rectum
Imagine you are a super cool slug hanging out in the peritoneal space with all the super cool organs - you’re just vibing and people are like “oh sweet, the SLUG SIcTS” (Think of the C as silent)
Which major artery supplies the hindgut?
Inferior mesenteric artery
Which major artery supplies the midgut?
Superior mesenteric artery
Which major artery supplies the foregut?
Celiac trunk
The ligamentum teres is a remnant of which embryologic structure?
Umbilical vein
Which ligament attaches the liver to the body wall?
Falciform ligament
Which of the following organs is secondarily retroperitoneal?
A. Duodenum
B. Transverse colon
C. Spleen
D. Superior mesenteric artery
E. Kidney
A. Duodenum
- Transverse colon and spleen have mesenteries (they are intra-peritoneal)
- Kidneys are primarily retroperitoneal
Which structures arise from the dorsal mesogastrium?
- Greater omentum
- Gastrosplenic ligament
- Splenorenal ligament
